Radiation-induced thickening and radiation-induced triggering for set-on-command sealent compositions and methods of use.

(54) Title: RADIATION-INDUCED THICKENING AND PRO-RADIATION-INDUCED ACTIVATION FOR SEALING COMPOSITIONS FOR CONTROL SET AND METHODS OF USE.

(54) Title: RADIATION-INDUCED THICKENING AND RADIATION-INDUCED TRIGGERING FOR SET-ON-COMMAND SEALENT COMPOSITIONS AND METHODS OF USE.

(57) Summary

The present invention includes methods and compositions related to the settlement of fluids or slurries in a well. In one representation, a method of isolating a part of a well includes preparing a sealing composition having a liquid component, a polymeric additive constituent, and a settlement modifying component. The sealing composition is placed in a well and subjected to ionizing radiation. Ionizing radiation can cause bonding between polymeric additive components and create a polymeric matrix within the sealant composition that increases the mechanical strength of the sealant composition. Ionizing radiation also alters the settlement modifying component, causing or activating the thickening of the sealant composition.

(57) Abstract

The present invention ineludes methods and compositions relating to the setting of fluids or slurries in a wellbore. In one embodiment, a method of isolating a portion a wellbore ineludes preparing a sealanl composilion having a fluid component, a polymeric additive constituent, and a set modifier component. The sealant composition is placed into a wellbore and subjected to ionizing radiation. The ionizing radiation can cause bonding between polymeric additive constituents and create a polymer matrix within the sealant composition that increases the mechanical strength of the sealant composition. The ionizing radiation also alters the set modifier component, triggering the thickening of the sealant composition.

_I KNOW__

MCRtatía 0Ϊ «CONOMtA

<img file="MX338668B_D0001.tif" />

Institute

Mexican Property

Industrial

I

M

P i

<img file="MX338668B_D0002.tif" />

PATENT TITLE NO.338668

Headlines):

Home:

Denomination:

HALLIBURTON ENERGY SERVICES, INC.

PO Box 1431, Duncan, Oklahoma, 73536, USA

RADIATION INDUCED THICKENING AND PRO RADIATION INDUCED THICKNESS FOR SEALING COMPOSITIONS FOR CONTROL SET AND METHODS OF USE.

<img file="MX338668B_D0003.tif" />

lnt.CI.8: C09K8 / 42lC09K8 / 508lE21 B33 / 13: AMU

IKRAI

MVI

<img file="MX338668B_D0004.tif" />

REQUEST *

Intemaclonab Filing Date 2012

ENTYI;

ICHAEL

R

US

Validity: Twenty-one

Date of Vene mienf »: 2nd patent of reference to grant c.

3e in accordance with art uto 23 di ¡ontada from the fetga of prei lerechos.

2who subscribes the presenil title to

<img file="MX338668B_D0005.tif" />

the fs —-. t · .- »- ia r ^ roptocmci ace based on the provisions of articles 6 ° sections III and 7 ° bis 2 of official foundation l Law of the regulation of industrial law.

twenty impi-irrigable years, to keep the lenses of the ey from / 05/1999,

01/26/2004, 06/16/2005, 01/25/2006, 06/05/2009, 06/01/2010, 06/18/2010, 06/28/2010, 01/27/2012 and 09/04 / 2012); Articles 1, 3 'section V subsection a), 4 and 12 sections I and III of the Regulation of the Mexican Institute of Industrial Property (DOF 14/12/1999, amended on 07/01/2002, 07/15/19 2004, 07/28/2004 and 09/07/2007); Articles 1, 3, 4, 5, section V, Section a), 16 sections I and III and 30 of the Organic Statute of the Mexican Institute of Industrial Property (DOF) 12/27/1999, amended on 10/10/2002, 07/29/2004, 08/04/2004 and 09/13/2007); 1st. 3rd and 5th Subsection a) of the Agreement that delegates powers to the Deputy Directors General, Coordinator, Divisional Directors, Holders of Regional Offices, Divisional Deputy Directors, Departmental Coordinators and other subordinates of the Mexican Institute of Industrial Property. (DOF 12/15/1999, amended on 02/04/2000, 07/29/2004, 08/04/2004 and 09/13/2007).

<img file="MX338668B_D0006.tif" />

Arenal No 550, Floor 1,

Col. Pueblo Santa María Tepepan, Xochimilco, CP 16020,

Mexico City

Tei. (5S) 53 34 07 00 www.imoigob.mx

Issue Date: April 27, 2016

THE DIVISIONAL DIRECTOR OF PATENTS. 1 ± NAHANNY CANAL REYES

<img file="MX338668B_D0007.tif" />

lillllllll

MX / 2016/32579

IMPI

MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY

<img file="MX338668B_D0008.tif" />

in general, to cementing operations

RADIATION INDUCED THICKENING AND INDUCED ACTIVATION

PRO RADIATION FOR SEALED COMPOSITIONS, SET PE HAMPO

AND METHODS OF USE.

Field of the Invention

The present invention relates to hydrocarbon exploration and production, such as underground operations and more particularly, to compositions and methods that allow greater control over the thickening and settling of fluids or slurries, such as cement during and after underground cementing operations.

Background.

Natural resources such as oil and gas located in an underground formation can be recovered by drilling a well bore at the bottom of the underground formation, typically while a drilling fluid circulates in the well. After the wellhead is drilled, a string of pipe, for example the casing, can be run into the wellhead. The drilling fluid then circulates, usually downward, through the inside of the pipe and upward, through the annular space between the outside

<img file="MX338668B_D0009.tif" />

<img file="MX338668B_D0010.tif" />

MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY of the pipe and the walls of the wellhead, although other methodologies are known in the middle.

Liquids and slurries, such as hydraulic cement compositions, are commonly used in drilling, completion, and repair of oil and gas wells. For example, hydraulic cement compositions are used in primary cementing operations whereby pipe chains, such as casing pipes or openwork pipes, are cemented into the manholes. In performing primary cementing, a hydraulic cement composition is pumped into the annular space between the walls of a well bore and the outer surfaces of a string of pipe disposed therein. The cement composition is allowed to settle in the annular space, thereby forming a substantially hardened waterproof cement annular sheath. This cement sheath physically supports and positions the pipe string relative to the borehole walls of a well and joins the outer surfaces of the pipe string to the borehole walls of a well. The cement sheath prevents unwanted migration of fluids between zones or formations penetrated by drilling a well. Hydraulic cementitious compositions are also commonly used to plug loss of circulation and other undesirable fluid in inlet and outlet areas in wells, to

<img file="MX338668B_D0011.tif" />

INSTITUTO MEXICANO Ct LA PROPIEDAD

INDUSTRIAL

<img file="MX338668B_D0012.tif" />

plug cracks and holes in cemented pipe strings and to perform other necessary corrective operations in well operations. After the cement is placed in a wellbore, it takes a period of time for the cement to cure and obtain sufficient mechanical strength to resume drilling operations. This downtime is often referred to as Waiting-Cement or WOC. If cement operations are resumed before sufficient mechanical strength is obtained, the structural integrity of the cement may be compromised.

Two common pumping methods have been used to place the cement composition in the annular space. The cement composition can be pumped down the inside diameter of the casing and up through the annular space to its desired location. This is known as a conventional-circulation direction method. Alternatively, the cement composition can be directly pumped down into the annular space, in order to displace the well fluids present in the annular space by pushing them upward on the inside diameter of the casing. This is known as the reverse-circulation direction method. Cement can also be used within a wellbore in other ways, such as by placing

MEXICAN INSTITUTE OF PROPERTY

INDUSTRIAL

<img file="MX338668B_D0013.tif" />

cement into a well bore at a desired location and lower a string of casing into the cement. The latter method can be used, for example, when there is no well fluid flow capacity due to fluid loss in a formation penetrated by drilling a well.

In performing primary cementing, as well as corrective cementing operations at manholes, cement compositions are frequently subjected to high temperatures, especially when cementing is carried out in deep underground areas. These high temperatures can shorten the thickening times of cement compositions, that is, the setting or setting of the cement takes place before the cement is properly pumped into the annular space. Therefore, the use of retardant additive kits has been required in cement compositions. These additives extend the setting or setting times of the compositions, so that an adequate pumping time is provided in which the cement is placed in the desired location.

While a variety of cement settling or setting retarding additives have been developed and used, known additives such as sugars or sugar acids can produce unpredictable results. Acids

MEXICAN INSTITUTE OF PROPERTY

INDUSTRIAL

<img file="MX338668B_D0014.tif" />

Hydroxycarboxylics, such as: tartaric acid, gluconic acid, and glucoheptonic acid are commonly used in cementing oil wells as a cement retarder. However, if an excess of hydroxy carboxylic acid is used, it may over retard the settling of the cement grout and thus cause it to remain fluid for an extended period of time. This excess delay may result in a long wait time before resuming drilling and may allow gas to invade the grout thereby causing migration of the unwanted gas. The long wait time results in delays in subsequent drilling or completion activities.

In a series of cementing applications, the aqueous salt has been used as an additive in cement compositions. Salt, usually sodium chloride, works as a dispersant in the cement grout, causing the grout to expand prior to settling, thereby achieving a good bond between the drilling of a well and the grout casing. However, salt-saturated grouts can cause problems to bordering formations and in certain situations, salt can be leached from the cement grout, which could lead to cement failure. Also, certain salts, such as calcium salts, can act as accelerating agents, which

<img file="MX338668B_D0015.tif" />

INSTITUTO MEXICANO DE LA PROPIEDAD reduces the setting or setting time of the cement composition in an attempt to overcome the negative effects of settling retarders. However, the presence of a setting and force accelerating agent, such as calcium salt, in the cement composition may increase the risk that the cement composition may thicken or settle prior to placement. Given the complexity of cement chemistry and the high temperature and pressure gradients present at the wellhead and the difficulty of predicting exact downhole temperatures during cement placement and settlement, it can be difficult to control that the additive retarder and accelerating agent behave appropriately to obtain the desired settlement. Systems are generally over-engineered to have a very long settling (or thickening) time, in order to ensure that the mix remains liquid until all of the cementitious material is in place, which can result in Excessive WOC.

Therefore, there is a need to improve settlement control methods and compositions, resulting in predictable set times of the cement composition, as well as fluid and slurry thickening times in the underground environments encountered. in wells. In particular, it is desirable to develop methods for

MEXICAN INSTITUTE OF PROPERTY

INDUSTRIAL

<img file="MX338668B_D0016.tif" />

Quickly thicken or thicken and settle such fluids, such as cement-based systems, whereby the fluid thickening and settling time is under the control of engineers in the field, without the risk of premature hardening. Therefore, there is a need for compositions and methods of using such compositions for the cementation of a well bore that would at the same time contain sufficient retarding material to ensure adequate pumping capacity for the desired time and a sufficient concentration of an accelerator to shorten the setting or setting time, therefore, the effect of thickening or thickening of the accelerator is under the control of technicians in the field.

Brief description of the invention.

The present invention relates, in general, to slurry and / or fluid compositions from drilling a well and methods of using such compositions, which allow greater control over the settling or setting of such compositions in drilling a well. water well.

In accordance with one aspect of the invention, there is provided a method of isolating a well bore within an underground formation, which comprises: placing a sealant composition comprising a polymeric additive and a setting or setting modifier in a borehole that penetrates a

<img file="MX338668B_D0017.tif" />

OI

MEXICAN INSTITUTE

OF INDUSTRIAL PROPERTY underground formation and subjecting the sealing composition to ionizing radiation. In accordance with another aspect of the invention, there is provided a useful sealing composition for the isolation of a well bore within an underground formation, comprising: a well drilling drilling fluid; a settling modifier and a polymeric additive, wherein the polymeric additive has a thickening or thickening capacity, previous exposure to ionizing radiation and the setting or setting modifier has a capacity to alter previous exposure to ionizing radiation.

Disclosed herein is a sealant composition having a well drilling fluid treatment component, a polymeric additive component and a settling or setting modifying component. The polymeric additive can be: a monomer, prepolymer, homopolymer, copolymer, terpolymer, hyperbranched polymer or dendritic polymer, a water soluble crosslinkable polymer, a comb polymer and combinations thereof, which crosslink when exposed to ionizing radiation . Also disclosed in the present work is a method of isolating a portion of a well bore by preparing a composition such as the sealant, placing the sealant composition at the wellhead and subjecting the sealant composition to the

IMPI

MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY

<img file="MX338668B_D0018.tif" />

ionizing radiation. Ionizing radiation can cause bonding between ~ polymeric additive components and creates a polymeric matrix within the sealant composition that increases the mechanical strength of the sealant composition. Ionizing radiation can cause destruction or degradation of at least part of the polymeric additive molecules, resulting in an increase in the mechanical strength of the sealant composition. Ionizing radiation can also alter the settling modifier, resulting in increased mechanical strength of the sealing composition.

The sealant composition may contain chemical retarders used to inhibit settling of the sealant composition, and ionizing radiation may cause the destruction of at least a portion of the chemical retarders, thereby reducing the fluidity of the sealant composition and increasing strength. mechanics of the sealing composition. The sealant composition may include one or more components selected from the group consisting of: sealants, resins, cements, sealable drilling muds, compliance fluids, and combinations thereof. The sealing composition may further include at least one scintillating material capable of emitting secondary ionizing radiation or non-ionizing radiation upon exposure to ionizing radiation.

IΜΡI

MEXICAN INSTITUTE OF PROPERTY

The polymeric additive can be: uñ^USTIUAmon ^ íTS? o7 prepolymer, homopolymer, copolymer, terpolyliitifu, —μυΙίΜΗΓσ dendritic or hyperbranched polymer. In representations, the polymeric additive can be selected from a poly (alkylene oxide), poly (vinyl pyrrolidone), poly (vinyl alcohol), a polyacrylamide, a polyacrylate, poly (methyl vinyl ether), and combinations thereof . In representations, the polymeric additive may be a water soluble crosslinkable polymer or a comb polymer.

The grout may further include sealing or cementing agents capable of reacting with the polymeric additive. Sealing or cementing agents can be selected from the group including: ethylene glycol, propylene glycol, diethylene glycol, polyvinyl pyrrolidone, polyvinyl alcohol, polyvinyl ether, polyacrylamide, polyols (alcohols containing multiple hydroxyl functional groups), polyacrylates, and combinations of the same. The grout may further include at least one scintillating material capable of emitting secondary ionizing radiation or non-ionizing radiation upon exposure to ionizing radiation.

The settling modifier may include one or more components selected from: an accelerator, an oxidizing agent, a settling retarder, or combinations thereof, and may include a polymeric component. The

ΙΜΡΙ

MEXICAN INSTITUTE OF LA MOPIEDAD

INDUSTRIAL

<img file="MX338668B_D0019.tif" />

Polymeric component can form an encapsulating layer on the settlement modifier particles. The polymeric component can be mixed with the slump modifier so that the polymeric components act as a binder and the resulting mixture can then be formed into a bar. The polymeric component can form an encapsulating layer on the tablet.

The polymer component can have a radiation tolerance ranging from about 1 Gray to about 500 KiloGrays and can be selected from the group consisting of: polyisobutylene, fluoroelastomers, silicone rubber, polyesters, polytetrafluoroethylene, polyacetals, polypropylene, copolymers of polypropyleneethylene, polymethylpentene, polymethylmethacrylate, fluorinated ethylene propylene, cellulose acetate, polymethylacrylonitrile, polyhexylsulfone-acetate, butyl acetate combinations.

The polymeric component may have a radiation tolerance of less than about 500 KiloGrays and may be selected from the group consisting of: copolymers of methyl methacrylate (MMA) with a chloro-substituted Qüo acrylate cyano; MMA-based polymers with fluorine incorporation in methacrylates; polymers having a CS bond, such as poly (butene-l-sulfone), polymers having a photosensitive acid generating group (PAG) in the structure of the

IMPI

MEXICAN INSTITUTE IS INDUSTRIAL PROPERTY polymer; polycarbonates such as poly-bisphenyl- carbonates

<img file="MX338668B_D0020.tif" />

A and bisphenyl-C; polyamides such as nylon; cellulose-based water-insoluble polymers such as Colloidon (nitrocellulose), acetate cellulose, and xanthate cellulose and combinations thereof. Optionally, the polymeric component may have a radiation tolerance of less than about 100 KiloGrays, optionally less than,

<td>approximately,</td><td> 10</td><td>KiloGrays,</td><td>optionally</td><td>less</td><td>of,</td>

<td>approximately,</td><td> 1</td><td>KiloGrays,</td><td>optionally</td><td>less</td><td>of,</td>

<td>approximately,</td><td> 100</td><td>Grays,</td><td>optionally</td><td>less</td><td>of,</td>

<td>approximately,</td><td> 50</td><td>Grays,</td><td>optionally</td><td>less</td><td>of,</td>

<td>approximately,</td><td> 10</td><td>Grays,</td><td>optionally</td><td>less</td><td>of,</td>

<td>approximately,</td><td colspan="2">5 Grays.</td><td></td><td></td><td></td>

<td colspan="2">The composition</td><td>sealer</td><td>can contain</td><td colspan="2">particles</td>

<td>photocatalytic</td><td>such</td><td>like T1O2,</td><td colspan="2">UNCLE2 doped 0 compounds</td><td>than</td>

They can improve the degradation of polymers when exposed to ionizing radiation. Photocatalytic particles can be nanoparticles.

The kit modifier may include an accelerator in an amount ranging from about 0.1% to about 20% depending on the weight of the sealant composition. Subjecting the sealant composition to ionizing radiation can allow the accelerator to react with compounds within the sealant composition to increase the mechanical strength of the sealant composition.

IMPI

MEXICAN INSTITUTE

FROM PROPERTY V »a» MÍS ^ e®K

INDUSTRIAL 'β * .—

The settlement modifier may also include an oxidizing agent in an amount ranging from about 0.05% to about 5% depending on the weight of the sealant composition capable of attacking any set retarder that is present. Subjecting the sealant composition to ionizing radiation may allow the release of the oxidizing agent, which reduces the retardant retardant capacity, allowing settling.

The settling modifier may include a settling retarder in an amount ranging from about 0.1% to about 10% depending on the weight of the sealant composition. The settlement modifier can be a sensitized retarder and can be a borated compound. Ionizing radiation may be sufficient to degrade the settling retarder, thereby reducing the retarding effect.

The composition may further include at least one sensitizing material to increase the capture efficiency of the ionizing radiation sealing composition. The sensitizing material can be a boron compound. The sealing composition may further include at least one scintillation material capable of emitting secondary radiation upon exposure to ionizing radiation. The sensitizing material may also be a scintillating material.

The grout can also be contained. s

IM

INSTITUTE

OF THE

<img file="MX338668B_D0021.tif" />

Chemicals used to inhibit grout -asitíiiLdiilleilLÓ and ionizing radiation can cause the destruction of at least part of the chemical retarders, thereby reducing fluidity in the cement phase and improving increased mechanical strength grout.

Ionizing radiation can be selected from the group consisting of: alpha rays, beta rays, gamma rays, neutron rays, proton rays, UV rays, and X-rays. Ionizing radiation can be emitted from a high-flux neutron source that can be selected from the group consisting of plutonium-beryllium, americium-beryllium, and americiolithium. The high-flux neutron source may be an accelerator-based neutron generator. Neutron radiation can be referred to as an ionization inducer or indirectly ionizing.

A radiation emitter can be placed at the bottom of a well bore and ionizing radiation can be emitted by a radiation emitter that is subject to control by technicians. Two or more radiation emitters can, optionally, be lowered separately to two or more depths from the wellhead, such that the two or more depths of a wellbore can be subjected to ionizing radiation simultaneously.

IMPI

MEXICAN INSTITUTE OF PROPERTY

INDUSTRIAL

<img file="MX338668B_D0022.tif" />

The present invention also relates generally to wellhead cementing methods that allow greater control over cement settling and grout thickening in a well bore.

One aspect of the invention provides a method of cementing a well bore that includes preparing a cement composition, which contains hydraulic cement and enough water to form a slurry, adding a polymeric additive, and settling modifier. of the composition, the placement of the cement composition in the drilling of a well and the subjection of the cement placed to ionizing radiation. Another aspect of the invention provides the same cement composition that includes sufficient hydraulic cement and water to form a suspension, a polymeric additive, and a settling modifier. In one aspect, ionizing radiation can induce crosslinking polymerization of at least a portion of the polymeric additive components and can create crosslinks between polymer chains, thereby creating a polymeric matrix anchored to two or more particles, to increase the mechanical strength of the composite material, sufficient to allow the resumption of activities such as completion procedures or continued drilling. Ionizing radiation can include neutron radiation, which can be

<img file="MX338668B_D0023.tif" />

IMPI

MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY denominate as ionization induction or indirectly ionizing.

The polymeric additive can be a monomer, prepolymer, or polymer. At least one part of the polymeric additive can contain at least one functional group that can adhere to the surface of the cement particles and at least one part of the polymeric additive contains at least one functional group that is soluble. in water and can form crosslinks when exposed to ionizing radiation.

Ionizing radiation destroys at least a portion of a polymeric component, resulting in an increase in the mechanical strength of the grout. Ionizing radiation can also act to release or activate one or more settlement modifiers, such as an accelerator. The accelerator can be combined with a polymer component, such as blends, where the polymer component acts as a binder, and then the resulting mixture is formed into a pellet. Ionizing radiation can cause the polymer component and facilitate the accelerator. The accelerator can be added in an amount of about 0.1% to about 20% by weight of cement. The polymeric component may have a tolerance to ionizing radiation less than, it may also cause degradation of the release of the

I

ΧΛ Γ ίΛ

MEXIL7-NÜ INSTITUTE OF PROPERTY

INDUSTRIAL approximately 500 KiioGrays. In an optional representation, the amount of ionizing radiation required to degrade a polymeric component ranges from about 1 Gray to about 500 KiloGray, optionally between about 1 Gray to about 100 KiloGray, optionally between about 20 Gray up to approximately 40 KiloGray. Ionizing radiation can be emitted from a high-flux neutron source.

At least one part of the polymeric additive can have at least one functional group that can adhere to the surface of the cement particles and at least one part of the polymeric additive can have at least one functional group that is Soluble in water and can form crosslinks when exposed to ionizing radiation. The polymeric additive may be a comb-like polymer that may include polycarboxylic acid (PCA) backbones that are absorbed on the surface of the cement particles and polyalkylene oxide (PAO) chains that extend into the aqueous phase of the cement composition. Polyalkylene oxide chains may be capable of crosslinking when subjected to ionizing radiation to create a polymer matrix within the cement composition in order to increase the mechanical strength of the composite material before the normal hydration setting of the

MEXICAN INSTITUTE OF PROPERTY

INDUSTRIAL

<img file="MX338668B_D0024.tif" />

cement. PAO chains can be polyethylene oxide chains. The cement composition may further include at least one scintillation material capable of emitting secondary or non-ionizing ionizing radiation upon exposure to ionizing radiation. Ionizing radiation allows the settlement modifier to react to increase the mechanical strength of the composition.

In addition, a cement composition containing a slump modifier and a comb polymer having cement anchor groups and pendant ionizable dispersion groups are described herein. Also described herein is a drill hole cementing method that includes preparing such a composition, placing the cement composition in the well, and subjecting the placed cement composition, mixed with the comb polymer to ionizing radiation, where ionizing radiation creates crosslinks between polymer chains. The cement anchor groups can be central axes of polycarboxylic acids in the comb polymers that are absorbed on the surface of the cement particles. Ionizable dispersion groups can be polyalkylene oxide chains that extend into the aqueous phase of the cement composition that can ionize and bond with adjacent ionized polyalkylene oxide chains to

<img file="MX338668B_D0025.tif" />

<img file="MX338668B_D0026.tif" />

MEXICAN INSTITUTE £. _Ί , z,,,, &lt;«ΠΕ PROPERTY, form a polymar matrix within the ®ο« φ © Νδΐ cement, in order to increase the reslstencj fl ... mprápj _rtCompound material before settlement of normal cement hydration. The cement composition and method may further include at least one scintillation material capable of emitting secondary radiation upon exposure to ionizing radiation.

Also described herein is a cement composition that includes a monomer, prepolymer, or polymer, in addition to a settling modifier for placement in a borehole subjected to ionizing radiation. Also described in the present work is a method of using such a cement composition and subjecting the composition to ionizing radiation. Ionizing radiation initiates the polymerization of the monomers or prepolymers and / or the crosslinking between the polymer chains of the ionized cement composition resulting from ionizing radiation, where the emission of ionizing radiation is subject to the control of technicians in the countryside. Ionizing radiation can also cause the settling modifier to react and affect the settling of the composition. The cement composition and method may further include at least one scintillation material capable of emitting secondary radiation upon exposure to ionizing radiation.

A cement composition can

V JL X

INSTITUTO MtXiO / '. NO OF INDUSTRIAL PROPERTY a have

<img file="MX338668B_D0027.tif" />

accelerating agent as a settlement modifier in addition to a polymeric additive. The accelerating agent can be encapsulated by a polymeric component that can degrade after exposure to ionizing radiation. A method of cementing a well bore may include preparing such a cement composition, placing the cement composition in the well, and subjecting the placed cement composition to ionizing radiation. The polymeric component in these two examples serves to isolate the accelerating agent from the cement composition. Ionizing radiation is sufficient to induce degradation of the polymer component, thereby dispersing the encapsulated accelerating agent in the cement composition. Ionizing radiation also causes bonding between polymeric additive components to create a polymer matrix in both examples.

A cement composition can comprise an oxidizing agent, a retarder and a polymeric additive. The oxidizing agent can be encapsulated by a polymeric component that can degrade after exposure to ionizing radiation, but the retarder is not encapsulated by a polymeric component. A method of cementing a well bore may include preparing a composition of this type of cement, placing the composition

MEXICAN INSTITUTE Γ. FROM THE INDUSTRIAL PROPERTY of cement in the drilling of a well and subjecting the cement composition placed to ionizing radiation. The polymeric component serves to isolate the oxidizing agent from the cement composition and from the retarder contained therein. Ionizing radiation is sufficient to induce degradation of the polymer component thereby dispersing the oxidizing agent encapsulated in the cement composition and subsequently degrading the retarder, thereby allowing settling. Ionizing radiation also causes the bond between the polymeric additive components to create a polymer matrix.

Also described herein in another aspect is a cement composition with a retarder and a polymeric additive, both of which react when exposed to ionizing radiation. Also described is a method of cementing a well bore that includes preparing a composition of this type of cement, placing it in a well bore, and subjecting the composition to ionizing radiation resulting from a neutron source. The radiation that is introduced into the cement composition is of sufficient strength to selectively alter or degrade the retarder molecules, thus allowing cure reactions to occur in the cement. Ionizing radiation also causes the bond between the polymeric additive components to create a polymer matrix. The retarder can be a sensitized retarder &lt;·

II

Α -'- ΐ Γ&gt; IV1. ί

INSTITUTE; ·· ν Ύ, ζ—

DE LA f. &lt;O?! EOAD industrial

<img file="MX338668B_D0028.tif" />

such as a bored retarder.

A cement composition can include an accelerating agent, a retarder, and a polymeric additive. When the composition is subjected to ionizing radiation, which is of sufficient strength to selectively alter or degrade the retarder molecules, the accelerating agent is allowed to produce a resultant effect in the rapid cure of the cement mixture. Ionizing radiation also causes the polymeric additive to react with the cement composition. The cement mix can include a sensitized retarder, a polymeric additive, and an accelerating agent added to a composition that includes cement and water. The accelerating agent can be encapsulated by a polymer capsule, which serves to isolate the accelerating agent from the cement composition. Introduction of ionizing radiation may be sufficient to induce degradation of the polymer capsule, thereby dispersing the encapsulated accelerating agent in the cement composition. Ionizing radiation can also cause bonding between polymeric additive components to create a polymer matrix.

A method of cementing a well may include preparing a cement composition that includes an accelerating agent, a retarder, and a polymeric additive,

OR

ΙΜ

INSTITUTO McXI&gt; -A ?, J de LA PROPIEDAD

INDUSTRIAL placement of the resulting cement composition in a borehole and subjecting the cement composition placed to ionizing radiation, which is of sufficient strength to selectively alter or degrade the retarder molecules, thereby allowing the accelerating agent take effect, resulting in rapid cure of the cement mix. Ionizing radiation also causes the polymeric additive to react with the cement composition.

The method may include preparing a cement mix by first adding a sensitized retarder, followed by adding an accelerating agent and polymeric additive for the composition that includes cement, water, and a sensitized retarder. The accelerating agent can be encapsulated by a polymer capsule that serves to isolate the accelerating agent from the cement composition. The step of introducing ionizing radiation may be sufficient to induce degradation of the polymer capsule, thereby dispersing the accelerator encapsulated in the cement composition. Ionizing radiation can also cause bonding between polymeric additive components to create a polymer matrix.

The foregoing has presented rather broadly, the characteristics and technical advantages of the present invention, in order that the description

<img file="MX338668B_D0029.tif" />

<img file="MX338668B_D0030.tif" />

THE detailed INDUSTRIAL Ü \ vrltUAU of the invention can be more fully understood. The characteristics and technical advantages of the present invention will be readily apparent to those skilled in the art upon reading the detailed description of the following representations of the invention. Brief Description of Drawings

Figure 1 illustrates a cross-sectional side view of a well bore.

Figure 2 is a graph of the results of a radiation dose study.

Figure 3 is a graph of the values ​​of the

Storage of a radiation dose study.

Figure 4 is a graph of the Modulus values

Loss of a radiation dose study.

Figure 5 is a graph of brittleness of a polymer due to neutron irradiation for films of various materials and thicknesses.

Figure 6 is a graph of gas permeability for two polymer films of different thickness after exposure to neutron irradiation

Figure 7 is a conductivity graph illustrating delayed release of an encapsulated material upon exposure to neutron irradiation.

Figure 8 is a graph of gel strength achieved over time with compositions of the present invention.

DETAILED DESCRIPTION

<img file="MX338668B_D0031.tif" />

INSTITLTO Μ ΞΧ ICANC.) D £ LA pro?; Eda »

INDUSTRIAL

<img file="MX338668B_D0032.tif" />

The present invention relates generally to well drilling operations involving fluids or slurries, and more particularly, to fluids or slurries containing polymer or polymer precursors that can be reacted in commands to provide thickness to the liquid or grout and containing accelerating and / or retarding agents that can release, activate and / or deactivate the command to provide thickness or seating to the fluid or grout. The fluids or slurries in the present work can be referred to as well drilling treatment fluid and can be any suitable fluid or slurry for drilling, completion, well repair or production operations, such as: cements, slurries drilling, loss of circulation fluids, fracturing fluids, conformity fluids, sealants, resins, etc ... and combinations thereof. The present invention relates to well drilling cementing operations and more particularly to well drilling cementing methods using cement compositions containing accelerating and / or retarding agents that can be released and / or deactivated on command. and polymeric additives that can form a polymer matrix through bonds upon exposure to ionizing radiation. The present invention also relates

<img file="MX338668B_D0033.tif" />

<img file="MX338668B_D0034.tif" />

INSTITUTO MEXICANO, ... OF LZ PROPERTY to the cement compositions that continue. polymeric and accelerating agents and / or re¿¿ £ dadae &amp; s_

The fluid or slurry can be a cementitious composition that generally includes water and a cement component such as hydraulic cement which can include: calcium, aluminum, silicon, oxygen and / or sulfur, which sets and / or hardens by reaction with water.

Referring to Figure 1, a cross-sectional side view of a wellhead 2 is illustrated. A casing pipe surface 4, having a wellhead 6 attached, is installed in the wellhead 2. The Casing 8 is suspended from the wellhead 6 to the bottom of the wellhead 2. An annular gap 10 is defined between the casing 8 and the wellhead 2. An annular flow line 12 communicates fluidly with the annular space 10, through the bore of a well 6 and / or the surface of the casing 4 with a valve ring 14. Flow line 16 it is connected to the wellhead 6 to allow fluid communication with the inside diameter of the casing 8 and a casing valve 18. At the lower end of casing 8, the casing is open to the wellhead 2 or has circulation ports on the walls of casing 8 (not shown) to allow for

<img file="MX338668B_D0035.tif" />

<img file="MX338668B_D0036.tif" />

FROM INDUSTRIAL PROPERTY fluid communication between ring 10 and liner pipe 8. '

A cement fluid composition can be pumped down from the casing 8 and flow upward to the annular space 10, while the fluid returns are taken from the ring 10 out of the flow line 12, in a typical direction of movement. Alternatively, the cement fluid composition can be pumped into the annular space 10, of the annular flow line 12, while the fluid returns are taken from the inside diameter of the casing 8, through the line flow 16. Thus, the fluid flows through the wellhead 2, in a reverse flow direction. The casing pipe may be a drill string after the completion of drilling operations. Drilling fluid can circulate out of the wellhead and be replaced with drilling fluid, completion fluid, different grout, and the like.

In an alternative method, a fluid composition, such as a cement slurry, can be placed inside the wellhead 2 and a tubular seal or fill, such as casing 8, can be lowered into the wellhead 2 , in such a way that the fluid composition is displaced in the annular surface 10, thus placing the composition of the fluid Mexican • SYíT'JTO inside the ring 10, without pumping of dicKáiei ^ mpo ^ bS of the fluid in the annular space 10. The amphprinr mptndn will be termed pudular cementation. The fluid composition can be a drilling fluid placed within the wellhead after drilling operations are completed.

Any cement suitable for use in underground applications may be suitable for the use of the present invention. The cement compositions used in the present invention include packaged hydraulic cement. Examples of hydraulic cements include, but are not limited to: Portland cements (for example, Class A, C, G, and H Portland Cements), pozzolan cements, gypsum cements, cement phosphate, high alumina cements, silica cements, high alkalinity cements and combinations thereof. Cements including slate, cement kiln powder or blast furnace slag may also be suitable for use in the present invention. In certain forms of representation, the board may include shale glazes; In certain other representations, the slate may include rough shale (eg, not shot from shale) or a mixture of rough shale and shale glaze.

The compositions used in the present invention generally include a base fluid. A wide variety

<img file="MX338668B_D0037.tif" />

<img file="MX338668B_D0038.tif" />

•• \ S7iTUTO MEXICANO of base fluids may be suitable for use with the present invention, including but not limited to Fin-ian.

aqueous-based base, a non-aqueous-based base fluid, and mixtures thereof. When the base fluid is water-based, it can include water that can originate from any source, with the understanding that the water does not contain excess compounds (for example, dissolved organic, such as tannins) that can negatively affect other compounds in cement compositions. For example, a cement composition useful for the present invention may include fresh water, salt water (for example, water containing one or more salts dissolved in it), brine (for example, water saturated with salt), or sea water . When the base fluid is not aqueous based, the base fluid can include any number of organic liquids. Examples of suitable organic liquids include, but are not limited to, mineral oils, synthetic oils, esters, and the like. In certain representations of the present invention where primary cementation is carried out, a water-based base fluid can be used. The base fluid may be present in an amount sufficient to form a suspension that can be pumped. More particularly, where the base fluid is water, the base fluid may be present in the cement compositions used in the present invention in an amount ranging from about 25% to about 150% by weight of cement (bwoc). When the

-.ΜΡϊ &lt;„_

MEXICAN INSTITUTE \_z&lt;?'

DL LA 1'Ρ.ΟΡί ·: ΟΛΟ .- * · DELA Γ ^ Η'ί ': ω. ^' ^ .; ·· INOUSTitíAL ** base fluid is water, may be present in cement compositions in a amount ranging from about 30% to about 75% bwoc. The base fluid can be present in the cement compositions in an amount ranging from about 40% to about 60% bwoc. The base fluid may be present in the cement compositions in an amount ranging from about 35% to about 50% bwoc. The cement composition can include a sufficient amount of water to form a cementitious grout that can be pumped. The water may be fresh water or salt water, for example, an unsaturated aqueous salt solution or a saturated aqueous saline solution, such as brine or sea water.

The fluid or suspension compositions used in the present invention may further include a set retarder. Settling retardant mixtures lengthen the time in which the composition of the fluid or grout remains fluid. These retarding mixtures therefore allow a fluid or slurry from a treatment fluid well bore, such as cement, to be pumped over long distances without the effect of premature hardening. A wide variety of settlement retarders may be suitable for your use.

<img file="MX338668B_D0039.tif" />

in the cement compositions used in the present invention. For example, the settling retarder may include, but is not limited to, phosphonic acid, phosphonic acid derivatives, lignosulfonates, salts, sugars, carbohydrate compounds, organic acids, carboxymethylated hydroxyethylated celluloses, synthetic co- or terpolymers having carboxylic acid and sulfonate groups and / or borate compounds. The settling retarders used in the present invention can be derived from phosphonic acid, such as those described in US Pat. No. 4,676,832, the description of which is incorporated in its entirety in this document. Examples of suitable borate compounds include, but are not limited to, sodium tetraborate and potassium pentaborate. Examples of suitable organic acids include, but are not limited to, gluconic acid and tartaric acid. In general, the retarder assembly is present in the cement compositions used in the present invention in an amount sufficient to delay the settling of the cement composition in an underground formation for a desired time. More particularly, the settling retarder can be present in the cement compositions used in the present invention in an amount ranging from about 0.1% to about 10% bwoc. Settlement retarder may be present in cement compositions

<img file="MX338668B_D0040.tif" />

used in the present invention in an amount ranging from about 0.5% to about 4% bwoc. The imposition of ionizing radiation can result in alteration or destruction of a settling retarding additive. As the settling retarder is altered by exposure to ionizing radiation, the effect of the settling retarder on the slurry is reduced and the slurry may settle faster than it would settle in the absence of ionizing radiation.

The settling retarders of the present invention may include a retarder containing a sensitizer, such as a retarder comprising boron. The sensitizer can also be a material that has a strong radiation absorbing property. The sensitizer can also be a scintillating material. The sensitizer can be any material that increases the efficiency of capturing ionizing radiation within the slurry. This sensitizer-containing retarder, also referred to as a sensitized retarder, may be a boron-containing retarder, also referred to as a borated retarder, which may include a wide variety of settling retarders, including the settling retarders described herein. , wherein the selected settlement retarder or combination or settlement retarders further include at least one

ΙΜΡΪβ “

ΤΓ you

ί.

MEXICAN INSTITUTE fx.

¡&gt; E PROPERTY, INDUSTRIAL-Boron atom. As discussed in the immediately preceding paragraph, sugars and / or carbohydrates and carbohydrates can be used as a retarder in the setting of a cement composition. In one representation, the retarder is a sensitized sugar or carbohydrate.

In a more specific representation, the sensitized retarder is boronized glucose. In an even more specific representation, borated glucose is represented by 3-0 (o-Carborany-l-ylmethyl) -D-glucose, as presented in US Pat. No. 5,466,679, for Soloway and his collaborators.

Optionally, the compositions used in the present invention may include a fluid loss control additive. A variety of pe control additives fluid loss may be suitable for use with the present invention, including, but not limited to, fibers, flakes, particles, modified guars, latex, and copolymers of methyl acrylamide sulfonic acid, such as those described in more detail in US Pat. Us. 4,015,991, 4,515,635, 4,555,269, 4,676,317, 4,703,801, 5,339,903 and 6,268,406, the descriptions of which are incorporated in their entirety, by reference, in the present work. In general, the fluid loss control additive is present in the cement compositions used in the present invention in an amount sufficient to provide a desired degree

<img file="MX338668B_D0041.tif" />

fluid loss control. More particularly, the fluid loss control additive may be present in the cement compositions used in the present invention in an amount ranging from about 0.1% to about 10% bwoc. The fluid loss control additive may be present in the cement compositions used in the present invention in an amount ranging from about 0.2% up to about 3% bwoc.

Optionally, the compositions used in the present invention may also include a mechanical properties modifier. Examples of suitable mechanical property modifiers may include, but are not limited to, gases that add to the surface (eg, nitrogen), additive-generating gas that can generate a gas in situ in a desired time (eg, dust aluminum or azodicarbonamide), hollow microspheres, elastomers (for example, elastic particles including a styrene / divinylbenzene copolymer), high aspect ratio materials (including but not limited to fibers), flexible graphite materials, vapor / liquid filled beads, resorbable matrix materials whose absorption is time dependent (initiated by, for example, degradation), mixtures thereof (for example, mixtures of microspheres and gases)

<img file="MX338668B_D0042.tif" />

IMPI iN &lt;TÍRUTO MEXICANO DF THE PROPERTY or similar. The optional mechanical property modifier may include a latex. —————— In cases where microspheres are added to a treatment fluid or slurry composition from a well bore, such as cement compositions useful in the present invention, the microspheres may be present in cement compositions in an amount ranging from about 5% to about 0.75% bwoc. The inclusion of microspheres in the cement compositions useful with the present invention can reduce the density of the cement composition.

Optionally, in cases where one or more gas generating additives are used as modifiers of mechanical properties in the fluid or slurry compositions used in the present invention, the one or more gas generating additives may include, but are not limited to, powder aluminum that can generate hydrogen gas in situ or may include azodicarbonamide which can generate nitrogen gas in situ. Other gases and / or gas generating additives may also be suitable for inclusion in the fluid or slurry compositions used in the present invention. In cases where a gas generating additive may be present in the cement compositions in an amount ranging from about 0.1% to about 5% bwoc. When the gas generating additive is aluminum powder, aluminum powder may be present

I Μ- Ρ ι '¡- ^ ΙΊΤυΤΟ ΊίΧ Ο - * a,' £ ^^

FROM THE? * 'Ί' ί

Jv. d.

: χ &lt;&gt;&gt; '?

'lN JuSTXÍAL r&gt;

in cement compositions in a charity ranging from about 0.1% to about 1% bwoc. When the gas generating additive is an azodicarbonamide, said azodicarbonamide may be present in the cement compositions in an amount ranging from about 0.5% to about 5% bwoc.

Optionally, the fluid or slurry compositions used in the present invention may also include suitable additional additives, including antifoaming agents, dispersants, density reducing additives, surfactants, weighting materials, viscosity agents, fly ash, silica, free water control agents and the like. Any suitable additive can be incorporated into the fluid or suspension compositions used in the present invention.

The fluid or slurry may include a polymeric additive which may be a monomer, prepolymer, homopolymer, copolymer, terpolymer, hyperbranched, dendritic polymer, a water soluble crosslinkable polymer, a comb polymer, and combinations thereof, which crosslink or crosslink. when exposed to ionizing radiation. The polymeric additive can be selected from the group of: a poly (alkylene oxide), poly (vinyl pyrrolidone),

IMP

INSTITUTO MEXICA DE LA PROPIED INDUSTR a polyacrylate,

MEXICAN INSTITUTE OF PROPERTY

INDUSTRIAL --the same.

Hereof pol (vinyl alcohol), a polyacrylamide, poly (methyl vinyl ether) and combinations of

The compositions and methods of use of the invention may also include sealing or cementing agents. The sealing or cementation agent can be selected from the group including: ethylene glycol, propylene glycol, diethylene glycol, polyvinyl pyrrolidone, polyvinyl alcohol, polyvinyl ether, polyacrylamide, polyols (alcohols containing multiple hydroxyl functional groups), polyacrylates and combinations of the same.

The fluid or slurry can include a monomeric additive. The monomer additive can be a synthetic or natural monomer. Examples of synthetic monomers include hydrocarbons such as ethylene, propylene, or styrene monomers. Other synthetic monomers that can be used include acrylic monomers such as: acrylic acid, methyl methacrylate, and acrylamide. The monomeric additive may be present in amounts of from about 0.01% to about 10.0% bwoc; optionally about 0.05% to about 7.5% bwoc; optionally approximately 0.25% to around 2.5% bwoc.

The liquid or slurry can include one or more ethylenically unsaturated monomer, which is polymerizable by ionizing radiation. The ethylenically unsaturated monomer

IΜ Ρ ί

TUT'u-Ó l MEXICAN INSTITUTE OF PROPERTY

INDUSTR1A1 can be any monomer containing one or more groups

CH2 = C &lt;, which are ionizing. Non-limiting radiation polymerizable examples of ethiienically unsaturated monomers that can be used include vinyl monomers such as N-vinyl-2-pyrrolidone, unsaturated esters of organic acids such as: 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, and the like, unsaturated acids such as: acrylic acid, methacrylic acid, and the like, unsaturated amides such as: acrylamide, methacrylamide, and the like.

Optionally, the slurry can contain ethiienically unsaturated monomers containing more than one CH2 = C &lt;group, which can function as a crosslinking agent. Non-limiting examples of ethiienically unsaturated monomers containing more than one CH2 = C &lt;include: N'Nmethylene bis (acrylamide) (MBA), polyethylene glycol diacrylate (PEGDA), tetra (ethylene glycol) diacrylate (TEGDA), and the like.

The ethiienically unsaturated monomers can undergo both polymerization and crosslinking and can therefore lead to gelation of the slurry at reduced radiation doses. Since the starting materials are monomers, a higher monomer charge than that possible with polymers can be used, without adversely affecting the rheology profile and therefore may give

IMPI

INSTITUTO MEJiiCA.NO DE LA PRCPJc'JAú leads to greater gel resistances and / or reduction of necessary radiation. ----

<img file="MX338668B_D0043.tif" />

The fluid or slurry can include a crosslinkable or crosslinkable prepolymer additive. The prepolymer additive may be an intermediate polymer or a reactive low molecular weight macromolecule or an oligomer capable of being cured by further polymerization. An example of a prepolymer is polyurethane prepolymer which is commercially available and well known in the art. Prepolymers can include crosslinkable functional groups that are connected to an element or compound, such as, for example, a crosslinkable prepolymer functional group attached to a polymeric material. The prepolymer additive may be present in amounts of from about 0.01% to about 10.0% bwoc; optionally about 0.05% to about 7.5% bwoc; optionally, about 0.25% to about 2.5% BWOC.

The fluid or slurry can include a polymer additive. Examples of the polymeric additive include a monomer, prepolymer, or polymer. The polymeric additive can be a hyperbranched homopolymer, copolymer, terpolymer, or dendritic polymer. The polymeric additive can be selected from a poly (alkylene oxide), poly (vinyl pyrrolidone), poly (vinyl alcohol), a polyacrylamide, a polyacrylate themselves.

poly (methyl vinyl ether)

<img file="MX338668B_D0044.tif" />

j □ 'J jk KIAL - combinations of

The polymeric additive can contain at least one functional group that can bind to the surface of the cement particles and at least one functional group that is water soluble and can form crosslinks or crosslinks when exposed to ionizing radiation . The polymeric additive can be a comb polymer. The polymeric additive may be present in amounts of from about 0.01% to about 25.0% bwoc; optionally about 0.05% to about 7.5% bwoc; optionally approximately 0.25% to around 2.5% bwoc.

The polymeric additive can be a superplasticizing polycarboxylate (PCS) polymer. Superplasticizers can be useful in reducing the amount of water required to fluidize a cement mixture and / or to impart thixotropic properties. PCS can include one or more polymers or copolymers, terpolymers, and polymeric additive solutions thereof. PCS can be a comb-type polymer. The comb-like polymer may have a polycarboxylic acid backbone and polyalkylene oxide (PAO) side chains that have either been grafted onto the central axis of polycarboxylic acid or attached to a polymerizable carboxylic acid that is subsequently polymerized. When

<img file="MX338668B_D0045.tif" />

Τ Α Λ ρ ϊ I ινί1 χ

MEXICAN INSTITUTE OF THE Efc) Hi '! ALJ

INDUSTRIAL ΪΞ-adds to a slurry of the main chains of acids the polycarboxy-linear axis can be absorbed on a surface of the particle. For example, with a cement slurry, the polycarboxylic acid backbones can be absorbed onto a surface of the cement particle, while the hydrophilic PAO chains extend into the aqueous phase. While the central axis of the polycarboxylic acid is absorbed on the cement surface, it is anchored to the cement surface and can resist forces to dissociate. PAO chains extend from the center of the polycarboxylic acid to the aqueous phase. PAO chains can then be ionized, such as through the imposition of ionizing radiation, and can react with PAO ionized chains that extend into the aqueous phase of an adjacent PCS polymer, attached to an adjacent cement particle. Ionized PAO chains can join with other ionized PAO chains that form a polymeric lattice structure, along the cement grout. The structure of the polymer network can impart stiffness to the cement grout prior to cement grout fixation, through the normal hydration settling process.

The polymeric additive may be a superplasticizing polycarboxylate comb polymer having a major axis of a polymer chain, which serves as an anchor group

<img file="MX338668B_D0046.tif" />

and that have dispersing pendant groups ησΝο ^ οΜζθΤΪσΒ ·; The number of non-ionized dispersing groups and their relative proportion is not limited within the present invention. The ratio of the anchoring groups of ionized particles can range from about 1: 100 to about 100: 1 with respect to non-ionizing dispersing groups. Alternatively, the ratio of the anchor groups of ionized particles can be from about 1:50 to about 50: 1; optionally about 1: 1 to about 25: 1, relative to non-ionized dispersing groups. The anchoring group of ionized particles can be absorbed on a surface of the particle, while the non-ionizing dispersing groups spread in the aqueous phase. The non-ionized dispersing groups can then be ionized, such as through the imposition of ionizing radiation, and can react with each other to form a polymer lattice structure, along the slurry that thickens the slurry. In addition, polycarboxylate polymer molecules are available with multiple lengths of pendant polyalkylene oxide groups, where selection of the correct ratio can control both retention of workability and the rate of crosslinking upon exposure to ionizing radiation.

Polymers

<img file="MX338668B_D0047.tif" />

Superplasticizing polycarboxylate (PCS) suitable for use in the present invention are commercially available from companies such as BASF and WR Grace, Sika, Nippon Shokubai, Kao Soap, Nippon Oil and Fats and others.

The polymeric additive may be a polymer selected from a group that includes polyalkylene oxide (PAO), poly vinyl pyrrolidone (PVP), polyvinyl alcohol (PVA), poly methyl vinyl ether (PVME), polyacrylamide (PAAm). The polymer chains can be dispersed within the aqueous phase of the fluid or in suspension and can be ionized, such as through the imposition of ionizing radiation, to react with adjacent ionized polymer chains. The junction of adjacent ionized polymer chains forms a crosslinked polymer structure throughout the fluid that imparts thickeners to the aqueous phase. The polymer lattice structure can impart thickening or thickening to cement the grout prior to cement grout fixation through the normal hydration settling process. In alternative forms of representation, the polymer lattice structure can thicken other fluids, such as the fluid used to seal a water-bearing zone or for a sealable drilling fluid. The polymeric additive can be a water soluble polymer that can crosslink after exposure to ionizing radiation. The polymeric additive can also be a comb polymer (lMPI | ga institute) M · A '-¹'· NF THE OWN °^to!? ^nE Industrial with at least two functional groups, some that can be anchored, such as a cement grain and ÓLrJs that can crosslink after exposure to ionizing radiation.

The imposition of ionizing radiation can result in alteration or destruction of the polymeric additive. As the polymeric additive is altered by exposure to ionizing radiation, the resulting altered polymeric additive may lead to thickening of the grout. The grout may thicken sooner than it would in the absence of ionizing radiation.

The compositions and methods of use of the present invention may also include an accelerator. The accelerator helps overcome possible delays caused by settling retarders by shortening the settling time of the slurry or fluid composition. A wide variety of accelerators may be suitable for use in the fluid or slurry compositions used in the present invention; the accelerator can include any component that reduces the settling time of a cement composition. For example, the accelerator can include alkali and alkaline earth metal salts, silicate, aluminate and amine salts, such as triethanolamine. The accelerator can be a calcium salt. The calcium salt can be selected from the group consisting of calcium formate, calcium nitrate, calcium nitrite and

<img file="MX338668B_D0048.tif" />

calcium. In a specific representation form, the accelerator is calcium chloride. The accelerator may be present in the fluid or slurry compositions used in the present invention in an amount ranging from about 0.1% to about 20% bwoc. The accelerator may be present in the cement compositions used in the present invention in an amount ranging from about 4% to about 12% bwoc.

The accelerators of the present invention can be combined with a polymer component. The accelerator can be encapsulated by the polymer component. In another aspect, the accelerator can be uniformly mixed with the polymer acting as a binder, the resulting mixture is then compressed to form a pellet or granule. In yet another aspect, the resulting sediment is ultimately encapsulated through a polymeric component. The polymer component used as a binder in the pellet or granule formation may be of a different composition than the polymer component used in the encapsulation of the pellet or granule. Furthermore, it can be a composition sensitive to alkaline hydrolysis, in such a way that the alkaline medium of the cement system contributes to its faster degradation. The encapsulating polymer layer can be applied using

<img file="MX338668B_D0049.tif" />

EU INSTITUTE&gt;

£&gt; e la.

a polymer coating method selected from the group consisting of dip coating, spray coating, extrusion coating, transfer printing, and any combination thereof. The encapsulating polymer layer can also be applied using any common polymer coating method.

The oxidizing agents of the present invention can be combined with one or more polymeric components. They may be present in an amount of about 0.05% to about 5% of the composition of the fluid or slurry and capable of attacking any settling retardant that is present. The oxidant can be encapsulated by the polymer component. In another aspect, the oxidant is uniformly mixed with the polymeric component that acts as a binder, the resulting mixture is then compressed to form a pellet or granule. In yet another aspect, the resulting sediment is ultimately encapsulated through a polymeric component. The polymeric component used as a binder in pellet or granule formation may be of a different composition than the polymeric component used to encapsulate the tablet and may be selected from a particularly oxidation resistant polymer. Subjecting the fluid or slurry composition to ionizing radiation may allow release

<img file="MX338668B_D0050.tif" />

approximately approximately

INSTITUTO MEXICANO 'DE LA of the oxidizing agent that reduces the retardant capacity of the retardant, thus allowing a-aenLπΐί

The polymer component that can be selected in the present invention is durable in the high alkalinity environment found in cement and exhibits low tolerance to ionizing radiation. The polymeric component may exhibit a radiation tolerance of less than approximately 500 KiloGrays; optionally less than,

250 KiloGrays; optionally less than,

100 KiloGrays. Alternatively, the polymeric component has a radiation tolerance ranging from about 4 to about 65 KiloGrays. Optionally, the polymeric component has a radiation tolerance ranging from about 1 Cray to about 500 KiloGrays; optionally between approximately 1 Gray up to around 100 KiloGrays and optionally between approximately 20 Gray up to around 40 KiloGrays. A non-limiting list of polymer degradation after exposure to ionizing radiation is presented in Table 1.

Table 1

<td>Polymer</td><td>Tolerance (kGy)</td>

<td>Teflon</td><td> 5</td>

% τ&gt; y

<td>Polyacetals</td><td>t? £ LA .'¡í'J .- 'it J ?. INLO'JSTaí * fifteen</td>

<td>Propylene Copolymers- Ethylene</td><td> 25-60</td>

<td>Aliphatic Nylons</td><td> 50</td>

<td>Polystyrene</td><td> 10.000</td>

<td>Phenolic</td><td> 50.000</td>

In one aspect, the polymeric component is selected from the group of polyisobutylene, fluoroelastomers, silicone rubber, polyesters, polytetrafluoroethylene (PTFE) (available under the trade name TEFLON® from EI du Pont de Nemours and Company), polyacetals (available under the EI DELRIN® trade name du Pont de Nemours and Company and under the trade name CELCON® from Ticona), polypropylene, polypropylene-ethylene copolymers, polymethylpentene, fluorinated ethylene-propylene, perfluoroalkoxy (PFA), polymethylmethacrylate (PMMA) and combinations thereof.

Referring to Figures 5 and 6, various polymer films were exposed to a neutron flux of 1.2 x 10¹³/ s and were tested for brittleness and gas permeability over time. The film material and thickness were PMMA at 50 microns; Delrin at 75 microns; PFA at 25 and 12.5., ¾

MEXICAN INSTITUTE Cz /^fc;You? ' micras and PTFE to 5 micras. Figure 5 illustrates that®Muílse'iA ^ 'MÍ ^ 3 a thickness of 50 microns shows an effect rip f ragi 1-id ^ ri an._r- approximately 18 minutes and in around 50 minutes the film had degraded to a degree that could no longer be tested. The dark area of ​​the bar shows when the brittleness is observed from the neutron flux and when it has degraded to a degree that can no longer be tested. It is also observed that some materials, such as Delrin, are more susceptible to radiation degradation than other materials such as PMMA.^- or PFA. Delrin film with a thickness of 75 microns degrades before PFA with a thickness of 12.5 microns.

Figure 6 illustrates the effect of film thickness on gas permeability and that the 25 micron thick PFA film retains gas tightness for about twice the time of a 12.5 micron PFA film. thickness exposed to the same radiation. Figure 6 also illustrates that both PFA films observed gas permeability at an earlier time when the embrittlement effect was observed, as shown in Figure 5.

Referring to Figure 7, a sample of sodium metasilicate, available as Econolite from Halliburton, was coated with a PFA layer of FluoroPel ™ and a PFA layer of FluoroPel ™ with B₄C. The sample was exposed to a flow of

IMPi

MEXICAN INSTITUTE OF PROPERTY

INDUSTRIAL 1.2 x 10 neutrons¹³/ s and conductivity was tested over time. Figure 7 shows that the coating provides a delayed release profile of sodium metasilicate, which is relative to radiation exposure. FluoroPel ™ is available from Cytonix Corporation.

In a further example, a sample of Uranin dye on a glass slide was encapsulated using FluoroPel ™ PFA, approximately 36 microns thick, in a fluid container. The encapsulated dye was exposed to a neutron flux of 1.2 x 1.0¹³/ s, for 50 minutes, during which time the uranine dye had visibly colored the fluid, indicating its dissipation in the liquid.

The polymeric component of the examples may also contain additional material to promote polymer degradation and / or accelerator release in the well treatment fluid or grout composition. A promoter for free radical chain breakage can be added to the polymer capsule and / or polymer component used as a plug to accelerate the degradation of the polymer once activated by exposure to ionizing radiation. The polymer component may also contain a sensitizer made of a material that has a strong radiation absorbing property. The promoter or sensitizer can be any material that increases the ilL JL Jl 77

MEXICAN INSTITUTE; á f DE LA PROPIEDAD V ^ wn ^ iA.wSr »· INDUSTRIA !.

capture efficiency of ionizing radiation within the grout. The promoter or sensitizer material can be a boron compound, such as boron carbide or boron nitride. The promoter or sensitizer material may have a tolerance to ionizing radiation of less than 500 KiloGrays; optionally, from 1 Gray to 500 KiloGrays.

The compositions of this invention may include the formation of a sealant composition containing the settlement modifier alone or in combination with a polymer component. The methods of this invention for the isolation of a portion of a wellhead may include the formation of such a sealant composition including a settlement modifier, pumping of the sealant composition containing the settlement modifier into a wellhead and subjecting the sealing composition to ionizing radiation after placement at the wellhead. The settlement modifier of the invention can be combined with a polymer component. The polymeric component can serve to prevent release of the settling modifier, such as an accelerator, into the sealant composition. The ionizing radiation introduced is sufficient to dissolve, degrade, or otherwise fail to break the polymer component, thereby allowing the settling modifier to be released into the sealant composition. Once the modifier is released, Ί,. . ,. , MEXICAN INSTITUTE of the settlement, scattered in the composicee® ^^ g¡ ^ l

IMPI

MEXICAN INSTITUTE reacts with it, resulting in the initiation of the

<img file="MX338668B_D0051.tif" />

settlement process. The release of ionizing radiation, which is under the control of those skilled in the art, thus acts as an activator in initiating settlement of the sealant composition.

The polymer component may be combined with the set modifier by encapsulation, bonding with the set modifier in a mixture, or both. The polymer coating used in the methods of this invention can be any polymer component that will degrade when subjected to ionizing radiation. The polymer component can be degraded by exposure to gamma radiation. Optionally, the polymer component can be degraded by exposure to gamma radiation at levels less than about 500 KiloGrays. In an alternative representation, the polymer component will degrade under exposure to gamma radiation at levels ranging from about 1 Gray to about 500 KiloGray; optionally between approximately 1 Gray to around 100 KiloGray; optionally between approximately 20 Gray to around 40 KiloGray. In yet another embodiment, the polymer will degrade under ionizing radiation

IMÍ

<img file="MX338668B_D0052.tif" />

ii [i \ ST; r / 'ú MSXiCANO emitted from a gamma ray generator iquéííjiiñitb used in well logging instruments of

The type and level of ionizing radiation used in the methods of this invention may depend on the polymer component (s) that are combined with the accelerator. The type and level of ionizing radiation may depend on what is capable of degrading the polymeric component (s). The type of ionizing radiation can include alpha rays, beta rays, gamma rays, 10-neutron rays, proton rays, UV rays, and X-rays or combinations thereof. Optionally, the amount of ionizing radiation required to degrade the polymer component (s) is less than approximately 500 KiloGrays. Optionally, the amount of ionizing radiation required to degrade a polymer component is between about 1 Gray to about 500 KiloGray; optionally between approximately 1 Gray to around 100 KiloGray; optionally between approximately 20 Gray to up to around 40 KiloGray.

The methods of this invention for the isolation of a wellhead may include the formation of a sealant composition including: a settlement modifier and a polymeric additive, pumping of the sealant composition containing the settlement modifier into a wellhead 25 and subjecting the sealing composition to ionizing radiation,

<img file="MX338668B_D0053.tif" />

<img file="MX338668B_D0054.tif" />

INSTITUI O MEXií after placement in the mouth of ροζό '^' Λβίί¹the settlement of the invention may_ be a rstarriarinr. optionally a sensitized retarder, such as a bored retarder. The sensitized retarder of the invention is susceptible to certain types of ionizing irradiation. The ionizing radiation introduced is sufficient to dissolve or otherwise break the retarder, thus allowing the sealant composition to settle to proceed. Ionizing radiation also causes bonding between the components of the polymeric additive to create a polymer matrix.

The sealant compositions of this invention can include a slump modifier and a polymeric additive. The settlement modifier of the invention may be a retarder, optionally a sensitized retarder, such as a bored retarder. The sensitized retarder of the invention is susceptible to certain types of ionizing irradiation. The ionizing radiation introduced is sufficient to dissolve or otherwise break the retarder, thus allowing the sealant composition to settle to proceed. Ionizing radiation also causes bonding between the components of the polymeric additive to create a polymer matrix.

The methods of this invention for the isolation of a wellhead may include the formation of a composition.

Ϊϊ li

MgKJHO INSTITUTE

<img file="MX338668B_D0055.tif" />

a

PE SEALING PROPERTY including: an accelerator and / or agent^uuÓWdan_l_c, retarder and a polymeric additive and The — exposure — tte — TcT sealing composition to ionizing radiation. The accelerator and / or the oxidizing agent can be released or activated by exposing the sealing composition to ionizing radiation, thus being able to accelerate the settling of the sealing composition. The retarder can be altered after exposure of the sealant composition to ionizing radiation, therefore, its ability to delay settling of the sealant composition can be hampered. The polymeric additive can react with the sealant composition to increase the mechanical strength of the sealant composition.

The sealing compositions of this invention may include an accelerator and / or oxidizing agent, a retarder and a polymeric additive, all of which are exposed to ionizing radiation prior to placement. The accelerator and / or the oxidizing agent can be released or activated by exposing the sealing composition to ionizing radiation, thus allowing the sealing composition to settle to be accelerated. The retarder can be altered after exposure of the sealant composition to ionizing radiation, making it difficult to delay settling of the sealant composition. The polymeric additive can react with the composition

<img file="MX338668B_D0056.tif" />

INSTITUTO MÍXICaNO D £ LA PROPERTY INDUSTRIAL sealant to increase the mechanical resistance of the sealant composition.

The methods of this invention for cementing a wellhead may include the steps of forming a cement composition including hydraulic cement and a sufficient amount of water to form a slurry, adding to the latter a desired amount of an accelerator or agent. oxidant and a polymeric additive; pumping the slurry containing the accelerator and / or the oxidizing agent and the polymeric additive into a wellhead and subjecting the slurry to ionizing irradiation after placement of the slurry into the wellhead. The accelerator and / or the oxidizing agent of the invention can be combined with a polymer component. The polymeric component serves to prevent the release of the accelerator and / or oxidizing agent in the cement grout. Ionizing radiation can cause the polymeric additive to form crosslinks or crosslinks in the cement composition. The ionizing radiation introduced is sufficient to dissolve, degrade or otherwise break the polymer component, thus allowing the accelerator and / or oxidizing agent to be released into the cement slurry. Once the accelerator and / or oxidizing agent is released, they disperse in the cement grout and react with the suspension or retarder, resulting in the initiation of the settling process. The

ΜΡΙ éil

<img file="MX338668B_D0057.tif" />

INSTITUTO MEXICANO release of ionizing radiation, which^OFeFrouent the control of the technicians in the matter, act.ÚA rip pg-a form, as an activator to start the settlement of the cement grout.

The cement compositions of the present invention can include hydraulic cement and a sufficient amount of water to form a slurry, an accelerator and / or the oxidizing agent and a polymeric additive. The accelerator and / or the oxidizing agent of the invention can be combined with a polymer component. Upon placement in a manhole and exposure to ionizing radiation, the constituents of the cement composition may react to affect the settling or thickening of the composition. Ionizing radiation can cause the polymeric additive to form crosslinks or crosslinks in the cement composition. The polymeric component serves to prevent the release of the accelerator and / or oxidizing agent in the cement slurry until the ionizing radiation introduced is sufficient to dissolve, degrade or otherwise break the polymeric component, thus allowing the accelerator and / or oxidizing agent to be released into the cement grout. Once the accelerator and / or oxidizing agent is released, they disperse in the cement grout and react with the suspension or retarder, resulting in the initiation of the settling process. The Liberation

IMPI

MEXICAN INSTITUTE __....

PRO?] AGE of ionizing radiation, found bSj^orOR^TRl^ l control of the technicians in the field, acts as the activator UUHlü ΊΤΓΓ 'activator to initiate the settlement of the cement grout.

The polymer component can be combined with the accelerator and / or oxidizing agent by encapsulation, bonding with the mixture, or both. The polymer coating used in the methods of this invention can be any polymer component that will degrade when subjected to ionizing radiation. In one embodiment, the polymer component will degrade upon exposure to gamma radiation. The polymeric component may alternatively or additionally degrade upon exposure to gamma radiation at levels less than about 500 KiloGrays. Optionally, the amount of gamma radiation required to degrade a polymer component ranges from about 1 Gray to about 500 KiloGray; optionally between approximately 1 Gray to around 100 KiloGray; optionally between approximately 20 Gray to around 40 KiloGray. The polymer can be degraded by ionizing radiation emitted from a gamma ray generator, which is also used in oil well recording instruments.

The type and level of ionizing radiation used in the methods of this invention may depend on the / ί! /; ™ '' ' ^x ‘ ^TO

<img file="MX338668B_D0058.tif" />

MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY polymer component (s) that are combined with the accelerator and / or oxidizing agent. The type and ~ nTveI of ionizing radiation may depend on what is capable of degrading the component (s) of the polymer (s). The type of ionizing radiation can include alpha rays, beta rays, gamma rays, X-rays, or combinations thereof. The amount of ionizing radiation required to degrade the component (s) of the polymer (s) may be less than approximately 500 Kilograms.

The methods of this invention for cementing a wellhead may include the steps of: form a cement composition including hydraulic cement and a sufficient amount of water to form a slurry, add to the slurry a desired amount of a retarder and a polymeric additive, pump the suspension containing the retarder and the polymeric additive into a wellhead and subjecting the grout to ionizing radiation, after placement of the grout at the wellhead. The retarder of the invention can be, as described in the present work, a retarder sensitized as a borated retarder. The sensitized retarder and the polymeric additive of the invention are susceptible to certain types of irradiation. The ionizing radiation introduced is sufficient to dissolve or otherwise break the retarder, thus allowing the cement grout to settle to proceed. The

<img file="MX338668B_D0059.tif" />

<img file="MX338668B_D0060.tif" />

<img file="MX338668B_D0061.tif" />

MEXICAN INSTITUTE OF PROPERTY ionizing radiation also causes the union^NDUS'&amp; h¹t components of polymeric additives for e-rcar-a mat-EÍE of polymer.

The cement compositions of this invention can include hydraulic cement and a sufficient amount of water to form a slurry, a desired amount of a retarder, and a polymeric additive. The retarder of the invention can be, as described in the present work, a retarder sensitized as an hourly retarder. The sensitized retarder and the polymeric additive of the invention are susceptible to certain types of irradiation. The ionizing radiation introduced is sufficient to dissolve or otherwise break the retarder, thus allowing the cement grout to settle to proceed. Ionizing radiation also causes bonding between polymeric additive components to create a polymer matrix.

The types and level of ionizing radiation used in the methods of this invention may depend on the type of sensitized retarder used. The types and level of ionizing radiation used may depend on what the molecules of the sensitized retarder are capable of altering or destroying. The ionizing radiation source can be a high flux neutron source. The high flux neutron source can be selected from the group consisting of:

<img file="MX338668B_D0062.tif" />

IΜ Ρ i

INSTITUTO MEXICaNC plutonium-beryllium, americium-beryllium and ^0ELAu ^^^

Optionally, the high-flux neutron source is an accelerator based on a neutron generator. The type of ionizing radiation may include: alpha rays, beta rays, gamma rays, proton rays, X-rays, or combinations thereof. Optionally, the amount of ionizing radiation required to alter or destroy the molecules of the sensitized retarder is less than approximately 500 KiloGrays. The sensitizer can also be a scintillating material.

The methods of this invention for cementing a wellhead may include the steps of: forming a cement composition including hydraulic cement and a sufficient amount of water to form a slurry; adding to the slurry a desired amount of either a conventional or sensitized settling retarder, an accelerator and / or the oxidizing agent and a polymeric additive; pump the slurry containing retarder and accelerator into a wellhead and subject the slurry to ionizing irradiation after placement in the wellhead. The accelerator and / or the oxidizing agent of the invention can be combined with a polymer component. The polymeric component serves to prevent the release of the accelerator and / or oxidizing agent in the cement grout. Settlement retarder, polymer component and additive

<img file="MX338668B_D0063.tif" />

Polymeric are susceptible to certain types d ^^ i ^ adrárrityn. The ionizing radiation introduced is suffer / lenle¹ to dissolve, degrade or otherwise break the polymer component, thereby allowing the accelerator to be released into the cement grout. Once the accelerator and / or oxidizing agent is released, it can be dispersed in the cement grout and react with the grout or retarder, resulting in the initiation of the settling process. The ionizing radiation introduced is also sufficient to dissolve or otherwise break the retarder, thus allowing the cement slurry to settle to proceed. Ionizing radiation also causes bonding between polymeric additive components to create a polymer matrix. The release of ionizing radiation, which is under the control of those skilled in the art, thus acts as a trigger to initiate the settlement of the cement grout, through the release of the accelerator and the alteration or sufficient destruction of the retardant.

The cement compositions of this invention can include hydraulic cement and a sufficient amount of water to form a grout; a desired amount of a settling retarder, either conventional or sensitized; an accelerator and / or the oxidizing agent and a polymeric additive. Accelerator and / or oxidizing agent

IMPI

MEXICAN UTUTO

<img file="MX338668B_D0064.tif" />

INSTITUI _, the invention can be combined with a compofí^lenÁr «sTÍ} p * ©Í The polymeric component serves to prevent the dhpraríÁn d. ^¹·· - accelerator and / or oxidizing agent in the cement grout. Settlement retarder, polymer component, and polymer additive are susceptible to certain types of irradiation. Upon placement at the wellhead, the cement composition may be exposed to ionizing radiation sufficiently to dissolve, degrade, or otherwise break the polymer component, thereby allowing the accelerator to be released into the cement slurry . Once the accelerator and / or oxidizing agent is released, they can disperse in the cement grout and react with the cement grout or retarder, resulting in the initiation of the settling process. The ionizing radiation introduced is also sufficient to dissolve or otherwise break the retarder, thus allowing the cement grout to settle to proceed. Ionizing radiation also causes the bond between the polymeric additive components to create a polymer matrix. The release of ionizing radiation, which is under the control of those skilled in the art, thus acts as a trigger to initiate the settlement of the cement grout, through the release of the accelerator and the alteration or sufficient destruction of the retardant.

IMPI

<img file="MX338668B_D0065.tif" />

INSTiTU ÍO Vl'XK \ NO

Dt la pkof: í.l&gt; aí),

The fluid or grout compositions and methods of the present invention may include, adorn_r- a-would kill !, scintillator. The scintillating material can act to increase the efficiency of capturing ionizing radiation and can emit ionizing radiation or non-ionizing radiation, upon exposure to ionizing radiation. A scintillating material with a fluorescence property can emit radiation, which can be referred to as secondary radiation, as a result of absorption of radiation from another source. For example, a scintillating material can emit gamma rays, X-rays, or UV radiation, upon exposure to neutrons or gamma rays. This secondary radiation can be used to provide radiation for the purposes of promoting polymer degradation and / or accelerator release in the liquid or slurry. If the secondary radiation includes photons or particles with the same wavelength as that of the absorbed radiation, it can be called resonance radiation.

A variety of neutron scintillators are known; a non-limiting list includes: LiF / ZnS: Ag, Li-glass and LiI: Eu. LiF / ZnS: Ag is shown to produce a large neutron multiplication factor and has been measured at 160,000 photons by absorbed neutrons, the majority of emissions of which occur below approximately 450nm. Li-glasses

MEXICAN INSTITUTE

DELA PROPERTY V '^ ariHaiiX

INDUSTRIAL ^ &lt;ü_SÍL— usually have an emission maximum below approximately 4 00 nm. .

A variety of scintillating gamma rays are known; a non-limiting list includes: NaI: Tl⁺, BÍ4Ge30i2 (GSO), Gd2SiO5: Ce³⁺, ZnS: Ag. Alkali halides include Csl and Nal. Maximum observed typical emission for some scintillators is: Csl - approximately 300 nm; BaF2 - about 190 to about 305 nm; CaF2: Eu - approximately 410 nm; GSO: Ce - about 420nm; Yal: CaTiO³: Ce - around 350 nm.

Organic Scintillators may include: Perkin Elmer Ultima Gold XR (aqueous compatible), EJ-301, EJ-305 from Eljen Technologies (compatible with non-aqueous solutions).

The scintillator can be used in powder or crystal form or with a coating, such as a polymer. Advantages of incorporating scintillators into the liquid or grout of the present invention may include the local creation of secondary radiation, which can minimize the impact of the well casing or other environmental influences. Potentially large multiplication factors are possible, for example some scintillators will emit more than 10,000 photons for each particle of ionizing radiation / photon absorbed. The photons produced by scintillators can be found in the spectral regions of X-rays and UV rays, which

IMPI, - · ¡&gt; 5 »can be highly absorbed by the polymer component of the suspension. Since these photons are created locally by scintillation, their emission can increase the degradation efficiency of polymer encapsulation. More photons above the threshold for radical generation from the polymer can increase the rate of polymer degradation or crosslinking through chain cleavage or both at the same time, depending on polymer chemistry. This process can accelerate the thickening of the cement grout and improve the behavior of the settling instruction.

Scintillation material can be added to the grout or to the wellhead treatment fluid. The scintillator can be incorporated into a polymeric additive. The scintillator material can also be incorporated into a polymer component that forms an encapsulating layer on the particles of an accelerator. The scintillator material can be added to a polymeric component that forms a binder for an accelerator that forms into a pellet and / or a polymeric component that forms an encapsulating layer on the pellet. The scintillation material can also be a sensitizing material. As used herein, the term polymer additive or polymer additive can include one or more than one polymer or one or more

<img file="MX338668B_D0066.tif" />

IN5T1TUTC MEXICANO

OF THE V PROPERTY of a polymer precursor, such as a ^IN¥ ftWÓme intermediate prepolymer or combinations thereof -

Various elements can be used as sensitized material. In general, elements that have a higher cross section absorption than that of the wellhead treatment fluid composition can be used to increase the efficiency of capturing ionizing radiation within the composition. Many wellhead treatment fluid compositions can include calcium, which has an absorption cross section of 2,200 m / s neutron of approximately 0.43 bam. A non-limiting list of elements having an absorption cross section of 2,200 m / s neutrons of 10 bam or greater is shown below in Table 2. A bam is defined as

IO '²⁸ m² and corresponds to approximately the cross-sectional area of ​​a uranium nucleus. Table 2. 2200 m / s neutron transverse absorption section

<td rowspan="2">Element</td><td colspan="2">Cross absorption section of</td>

<td>2,200 m / s</td><td>(bam)</td>

<td>Li</td><td colspan="2"> 71</td>

<td>B</td><td colspan="2"> 767</td>

<td>Cl</td><td colspan="2"> 34</td>

<td>I know</td><td colspan="2"> 28</td>

<td>Mn</td><td colspan="2"> 13</td>

<td>Co</td><td colspan="2"> 37</td>

<img file="MX338668B_D0067.tif" />

<img file="MX338668B_D0068.tif" />

MEXICAN INSTITUTE PE THE PROPERTY

<td>Au</td><td>INDUSTkCTL ' 99</td>

<td>H H</td><td> 372</td>

The polymeric additive and settling retarder and / or accelerator and / or oxidizing agent can be added to a cement mix before adding water to the mix. The polymeric additive and slug retarder and / or accelerator and / or oxidizing agent can be added to a cement mix after water has been added to the mix. The polymeric additive and settling retarder and / or accelerator and / or oxidizing agent can be added to the water to be added to a cement mix. The polymeric additive and the settling retarder and / or the accelerator and / or the oxidizing agent can be added during the mixing of a cement and water. Different polymeric additives and setting retarders and / or accelerators and / or oxidizing agents can be added at any one time separately, as described above, during the preparation of the cement mixture. The accelerator can be added before the overall retarder and the polymeric additive.

Once the cementitious composition containing the polymeric additive and the settling retarder and / or the accelerator and / or the oxidizing agent is obtained, the mixture can then be placed in the wellhead, such as in a wellhead / casing pipe ring. After placing the cement mixture that

<img file="MX338668B_D0069.tif" />

INSTITU, O Μ £. &lt;ANO DE LA? »()!&gt;! TUAD INDUSTRIAL contains the polymer component and“ 75Ί settling retarder and / or accelerator and / or oxidizing agent at the wellhead, cement particles they would be in intimate contact with each other and the settling retarder and / or accelerator and / or oxidizing agent, in a substantially uniform mixture. The polymer chains absorbed from neighboring particles must also be mixed with the cement particles and settling retarders and / or accelerating agent.

A settling retarder and polymeric additive, as well as an accelerator and oxidant, can be added to the fluid or slurry. When exposed to ionizing radiation, both the accelerator and the oxidant are released. The simultaneous destruction of the retarder by the oxidant and the acceleration of the hydration of the cement by the accelerator, provide rapid settlement. Furthermore, ionizing radiation also causes the bond between the polymeric additive components to create a polymer matrix.

In accordance with representations of the invention, after the intermixed composition is placed at the wellhead, ionizing radiation is introduced. Ionizing radiation contains subatomic particles or electromagnetic waves that are strong enough to detach electrons from atoms or molecules, thus ionizing them. The occurrence of ionization depends on the energy of the invading electromagnetic particles,

4ΡΪ

MEXICAN INSTITUTE OF THE PSO.'ltUAU

INDUSTRIAL individual or waves which must have energies above the ionization threshold (i.e. photoelectric effect). An intense flood of particles or waves may not cause ionization if these particles or waves do not have enough energy to be ionizing. The amount of ionizing radiation introduced into the well can be determined by the amount of ionizing radiation required to ionize the monomer, prepolymer, or chain polymer of the polymeric additive to sufficiently alter the polymer component to allow the release of at least a portion of the accelerator and / or oxidizing agent. Ionizing radiation can be emitted from or in the form of charged particles.

The charged particles can include alpha particles, beta particles, or gamma particles or combinations thereof. Optionally, the amount of ionizing radiation required to ionize constituents of polymeric additives is between about 500 KiloGray; optionally between approximately 1 KiloGray up to around 100 KiloGray; optionally between approximately 4 KiloGray up to around 40 KiloGray. The amount of ionizing radiation emitted is determined by the level of crosslinking desired and

KiloGray up

IMPIOS

MEXICAN INSTITUTE

FROM THE p; (0?; ​​Euad C5 = «¿&gt; -kSz

INDUSTRIAL -^v the type of polymer added to the cement mix. As described above, the amount of ionizing radiation required to alter or destroy sensitizing retarder molecules, including a scintillator, is less than approximately 500 KiloGrays. The fluid or slurry may further include at least one scintillation material capable of emitting secondary radiation upon exposure to ionizing radiation. The scintillator material may be able to reduce the required ionizing radiation. The scintillator material may be able to reduce the required ionizing radiation to less than half that required without the scintillator material.

Ionizing radiation can be introduced through an ionizing radiation emitter located at a point within the wellhead. A surface-mounted ionizing radiation emitter can introduce downward-directed ionizing radiation into the wellhead. A radiation source can be lowered into the wellhead, such as in a cable, and ionizing radiation can be emitted. The radiation source can be shielded or shielded so as not to emit radiation other than when the lead shield is removed. For example, a radiation source can be protected on the surface when personnel can be exposed in any other way. Once the radiation source is placed in the wellhead and the radiation

IMPI

MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY

<img file="MX338668B_D0070.tif" />

Ionizing can be safely emitted, the shield can be removed or opened, such as by an electronically activated signal, transmitted from the surface through wiring to the shield. The radiation emitter can emit ionizing radiation as it descends through the wellhead and as it is pulled up through the length of the wellhead. Two or more radiation emitters can be lowered separately to two or more depths, such that two or more depths of the wellhead can be subjected to ionizing radiation simultaneously.

Ionizing radiation can be introduced under the control of a technician in the field. The technician, engineer, or other on-site employee may have control over the emission of ionizing radiation through the placement of a signal that causes a release of ionizing radiation from an emitter. Ionizing radiation can be released at the request of the technician in the field. Ionizing radiation can be released by a control system that has parameters such as: timer, flow meter, temperature sensor, or the like. The reduction and / or emission of the ionizing radiation source can be caused by a timing mechanism. The reduction and / or emission of the ionizing radiation source can be caused by a

IMPI

INSTI TUTO MEXICANO PE LA PROPIEDAD

INDUSTRIAL

<img file="MX338668B_D0071.tif" />

flow meter that detects the amount of intermixed composition delivered to the wellhead.

When ionizing radiation is introduced, a network of crosslinks can be created between the polymeric additive chains. This may be the result of ionizing radiation in the polymeric additive chain and of the effects of ionizing radiation on other compounds present such as, water and solvents. Radiation, such as alpha radiation, can also initiate the dissociation of molecules that can be termed radiolysis. Radiolysis of water can generate hydroxide radicals, which can remove hydrogen from polymer chains and thereby form a polymer radical. Polymeric radicals can combine through intermolecular and / or intramolecular crosslinking or crosslinking and produce a gelled state. Radiolysis of other compounds such as solvents, (solvent radiolysis) can generate intermediates that can also react with the polymeric additive chain. Such a network of crosslinks or crosslinks increases the mechanical strength of the intermixed composition, for example, a cement compound before the typical settling of cement hydration.

Radiolysis of water and the subsequent generation of hydroxyl radicals can be increased by adding ιμ: ρι »3

INLT ¡TUTO Μ ·. X ί CA Ν OV^{CE tA}, f / I? ^^EDAn

INDUSTRIAL a radiocatalytic material. The radiocatalytic material, - mi 11 n ii m —i when exposed to ionizing radiation, increases the production of hydroxyl radicals by increasing the radiolysis of the water present in the composition. Hydroxyl radicals can extract hydrogen from polymer chains and thus form a polymer radical. The polymeric radicals can combine through intermolecular and / or intramolecular crosslinking or crosslinking and produce gelation of the polymer chains. Incorporation of radiocatalysts in cementitious grout compositions can improve the radiolysis of water within the composition, after exposure to ionizing radiation, thereby reducing the radiation dose necessary to allow crosslinking or crosslinking and the resulting increase in the mechanical resistance of the sealing composition.

A non-limiting list of materials that can function as a radiocatalyst are metal oxides such as: TÍO2, SÍO2, AIO2, CeC&gt; 2, ZeC&gt; 2, BeO, and combinations thereof. The radiocatalyst can be a nanoparticle or optionally, it can vary in size from tens of nanometers to micrometers in diameter.

The catalytic effect of radiocatalysts can be enhanced by the presence of suitable sensitizers, such as: tin chloride (also known as νίΡΙ chloride,

INSTITUTE v.cX.LANO DE LA FaUrltDAD tin (II) or tin di-chloride). Chloridene sphan can catalyze the crosslinking of 'Sh ÜU'lUdiÓli' polymers under ionizing radiation conditions. The sensitizer may include other tin-based materials, such as tin sulfate. The sensitizing effect of tin (II) salts can be increased in the presence of metal oxides. Non-limiting examples of metal oxides that can be used include: AI2O3; CeC&gt; 2; ZnO; BeO; NiO; S1O2 and combinations thereof. These metal oxides can be found in various forms, such as the case of silica, which could be amorphous silica, colloidal silica, silica fume or surface treated silica particles. Metal oxides can also be provided by fly ash, which can also provide more strength over time, due to pozzolanic activity. Examples of compositions incorporating sensitizers are presented in Example 9. Molecular oxygen is an effective scavenger of free radicals such as those created by radiolysis of water. Therefore, the presence of molecular oxygen in the slurry can inhibit the desired radiation-induced crosslinking or crosslinking. During radiation, the macro polymer radicals can react with oxygen to form corresponding peroxy radicals. These peroxy radicals are generally nonreactive and therefore inhibit

IMP

<img file="MX338668B_D0072.tif" />

MEXICAN INSTITUTE

PE PROPERTY 'additional crosslinking or crosslinking. The incorporation of an antioxidant scavenger or barredÓT CHS Oxygen and / or '^ Úñ ”in the slurry, can inhibit the formation of peroxy radicals and thus aid in the radiation-induced crosslinking or crosslinking of the polymeric additive. Non-limiting examples of an oxygen scavenger or scavenger that can be used in the present invention include: tin salts such as: SnCl2 and SnSO₄; phosphonium tetrakis (hydroxymethyl) chloride; phosphonium tetrakis (hydroxymethyl) sulfate; sulfoxialte formaldehyde sodium, thiourea dioxide; sodium diothionite; sodium hydroxymethanesulfinate hydrate , sodium hydrosulfite (sodium dithionite); formamidinesulfpinic acid (thiourea dioxide) and combinations thereof.

The modification of the mechanical resistance of the fluid, grout or compound, depends on the level of crosslinking or crosslinking. Low crosslinking or crosslinking densities can increase the viscosity of the composition to a rubbery consistency, and high crosslinking or crosslinking densities can cause the composition to stiffen. In one embodiment, ionizing radiation is introduced such that a low level of crosslinking or crosslinking is achieved, followed by another introduction of ionizing radiation, such that ultimately a higher level of

<img file="MX338668B_D0073.tif" />

<img file="MX338668B_D0074.tif" />

MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY cross-linking. Increasing the mechanical strength of the cement composite material, before the typical cement hydration settling may allow activities to resume at an earlier time, compared to waiting for cement hydration settling.

When the polymeric additive is a polycarboxylate superplasticizer, ionizing radiation can be used to crosslink or crosslink neighboring polymer chains in the aqueous medium. Particles can be separated by steric hindrance caused by anchored polymer chains, resulting in very few crosslinks or crosslinks, being necessary to create a continuous crosslinked or crosslinked network resulting in increased strength. This effect can be further enhanced by adding agents to the aqueous phase, which can increase the density of potential reagents in the vicinity of the particles and improve the kinetics of the radiation-enhanced settling process of the present invention, without otherwise affecting the properties of the fluid, grout or compound, such as a cement composition.

The ionizing radiation of the present invention can destroy molecules as well as cause crosslinking. For example, the destruction of polymer chains and chemical retarders used to inhibit settlement

ΙΜΡΪ

INSTITUTO MEXICANO DE LA PROPIEDAE can also serve to reduce effective fluidity^ÜUTS^{TO THE} fa? cement. The destruction of the poiimérioao chains could cause, but is not limited to, the release of encapsulated acceleration and / or oxidizing agents. This destruction of polymer chains and chemical retarders can also improve the increase in mechanical resistance of the process. Rather than being problematic, this result of the invention may serve to improve the performance of the aspect of the present invention, settlement instruction.

The cement compositions described in this document may also contain a water soluble crosslinking or crosslinking agent to facilitate the reaction between two polymer chains. The water soluble crosslinking or crosslinking agent can be a low molecular weight species that has good mobility in the aqueous phase and high reactivity against free radicals that are created by ionizing radiation of the polymeric additive. In one embodiment, the water soluble crosslinking or crosslinking agent is a water soluble polymer. The water soluble crosslinking or crosslinking agent may be a molecular weight, water soluble high weight polysaccharide. The water soluble crosslinking or crosslinking agent can be selected from the group consisting of: ethylene glycol,

<img file="MX338668B_D0075.tif" />

MF.XICANO INSTITUTE

Dt PROPIEUAu diethylene glycol, propylene glycol, poyalkyleneoxides such as. ——I - τπτττττ-^- polyethylene oxide, polyvinyl alcohol, and polycarboxylic acids such as polyacrylic acid, citric acid, butane tetracarboxylic acid, and the like.

Multifunctional crosslinkers include: diacrylates poly (ethylene glycol), dimethacrylates poly (ethylene glycol), trimethylolpropane triacrylate (TMPTA), TMPTA ethoxylated, trimethacrylate-triethyl-acryl-triethylaryl-triethylaryl-triethylaryl-triethylaryl-triethylaryl, triethylaryl, triethylaryl, triethylaryl, triethyl, triethyl, triethyl, triethyl, triethyl. triallyl-l, 3,5-triazine-2,4,6 (1H, 3H, 5H) trione, 2,4,6-triallyloxy-l, 3,5-triazine, alkoxylated bisphenol A diacrylate, the like and mixtures thereof.

As mentioned above, the ionizing radiation of the present invention can be under the control of those skilled in the art. Ionizing radiation emissions can induce a preliminary increase in the mechanical strength of the cement composition, before the cement hydration settles. The release of ionizing radiation emissions can act as a trigger, in the sense that radiation can destroy the sensitized retarder, thereby allowing the cement slurry to settle. The release of ionizing radiation can also act as a trigger

<img file="MX338668B_D0076.tif" />

ΙΜΡΪ

MEXICAN INSTITUTE OF INDUSTRIAL MOPIEDAD when ionizing radiation emissions act to degrade the polymer component of the accelerator and / or the oxidizing agent, thus releasing the accelerator and / or the oxidizing agent or both, in the cement slurry. Once the accelerator and / or oxidizing agent is released, it disperses in the cement slurry and reacts with the aqueous suspension or retarder, resulting in the acceleration of the settling process. Therefore, the increase in mechanical resistance The specific composition of the invention is under the control of technicians in the field. Such control may result in a decrease in the time required to wait for cement (WOC) in the drilling and completion of a wellhead. The WOC time of the cement composition of the invention containing ionizing radiation, the reactive polymeric additive may be less than the WOC time of a substantially similar cement composition that does not contain the polymeric additive. The cement composition of the invention can reduce the WOC time by at least one hour, at least two hours, at least five hours, or at least 10 hours, compared to a substantially similar cement composition that does not contain the polymeric additive. .

EXAMPLES

Example 1

IMPI fes

MEXICAN INSTITUTE

OF THE Oto PROPERTY

INDUSTRIAL

800 grams of a Class H cement was mixed with 320 ml of water (to produce water-for-cement, w / c, ratio 0.40) and 0.5% bwoc of one MW PEO 900,000 (polyethylene oxide) to form a grout. The grout also contained 0.50% bwoc of maltrodextrin, a cement settling retarder. The grout was mixed for 45 seconds in a high shear Waring blade mixer. The grout was divided into two samples. One sample was exposed to 4.3 Mrad of exposure to gamma radiation from a Co-60 source, while the other was kept as a control. The control sample that was not irradiated was still fluid (yield point measured at 3.5 Pa), while the gamma-irradiated sample had either crosslinked or crosslinked and was completely solid.

Example 2

Several suspensions were prepared using a Class H cement, water (to produce water-for-cement, w / c, ratio 0.40) with two different PEOs (100,000 MW and

900,000 MW). Other components in the grouts were: a polycarboxylate ether (dispersant), diutane gum (viscosity modifier) ​​and maltodextrin (retarder). Mixing specifications for grouts are shown in Table 3.

Table 3 - Mixing Specifications for Grout

<img file="MX338668B_D0077.tif" />

used in crosslinking or crosslinking experiments.

<td>Design</td><td></td><td colspan="2">Mix</td><td>Mix #</td><td>Mix #</td><td>Mix #</td><td>Mix</td><td>Mix</td>

<td>Mixture</td><td></td><td colspan="2"> #1</td><td> 2</td><td> 3</td><td> 4</td><td> #5</td><td> #6</td>

<td>Cement</td><td>grs</td><td> 800</td><td colspan="2"> 800</td><td> 800</td><td> 800</td><td> 800</td><td> 800</td>

<td>Water</td><td>grs</td><td> 316,4</td><td colspan="2"> 316, 4</td><td> 320</td><td> 320</td><td> 320</td><td> 320</td>

<td>Delayed</td><td>grs</td><td> 4</td><td colspan="2"> 4</td><td> 4</td><td> 4</td><td> 4</td><td> 4</td>

<td>r</td><td></td><td></td><td colspan="2"></td><td></td><td></td><td></td><td></td>

<td>(Maltodex</td><td></td><td></td><td colspan="2"></td><td></td><td></td><td></td><td></td>

<td>trina)</td><td></td><td></td><td colspan="2"></td><td></td><td></td><td></td><td></td>

<td>Name</td><td>grs</td><td>ADVA5</td><td colspan="2">ADVA575</td><td>Melflu</td><td>Melflu</td><td>Melfl</td><td>Melfl</td>

<td>Scatter</td><td></td><td> 75</td><td colspan="2"></td><td>x 1641</td><td>x 1641</td><td>ux</td><td>ux</td>

<td>tea</td><td></td><td></td><td colspan="2"></td><td></td><td></td><td> 1641</td><td> 1641</td>

<td>Scatter</td><td>grs</td><td> 0,40</td><td colspan="2"> 0,40</td><td> 1,00</td><td> 1,00</td><td> 1, 00</td><td> 1,00</td>

<td>tea</td><td></td><td></td><td colspan="2"></td><td></td><td></td><td></td><td></td>

<td>Solids</td><td></td><td></td><td colspan="2"></td><td></td><td></td><td></td><td></td>

<td>Totals</td><td></td><td></td><td colspan="2"></td><td></td><td></td><td></td><td></td>

<td>Scatter</td><td>grs</td><td> 6</td><td colspan="2"> 6</td><td> 2,4</td><td> 2,4</td><td> 2,4</td><td> 2,4</td>

<td>tea</td><td></td><td></td><td colspan="2"></td><td></td><td></td><td></td><td></td>

<td>VMA (Rubber</td><td>grs</td><td> 3,2</td><td colspan="2"> 3,2</td><td> 3,2</td><td> 3,2</td><td> 3,2</td><td> 3,2</td>

<td>Diutan)</td><td></td><td></td><td colspan="2"></td><td></td><td></td><td></td><td></td>

<td>PEO MW</td><td>grs</td><td> 100.0</td><td colspan="2"> 900.000</td><td> 100.00</td><td> 900.00</td><td> 100.0</td><td> 900.0</td>

<td></td><td></td><td> 00</td><td colspan="2"></td><td> 0</td><td> 0</td><td> 00</td><td> 00</td>

<img file="MX338668B_D0078.tif" />

[00131] All slurries were exposed to 4.3 Mrad of gamma radiation from a Co-60 source and it was found that the crosslinking and the gel on exposure to gamma radiation, while the controls were not irradiated, were still in a fluid state. Performance points for controls were determined using a FANN®35 viscometer and are shown in Table 4. None of these measurements was possible on the gelled samples.

Table 4 - Performance point measurements of controls for crosslinking or crosslinking experiments.

<td>Mix ID</td><td>Performance Point (Pa)</td>

<td> 1</td><td> 92</td>

<td> 2</td><td> 94</td>

<td> 3</td><td> 110</td>

<td> 4</td><td> 96</td>

<td> 5</td><td> 110</td>

<td> 6</td><td> 122</td>

? · Tr

INSTf.'UTÜ ΜΕ&gt; ·: Γ. ··. · .Ό of the:,; g: age

INDUS i HJAL

<img file="MX338668B_D0079.tif" />

Example 3

800 grams of Class H cement was mixed with 320 mL of water (w / c = 0.40) and 0.5% 360,000 MW bwoc a poly (vinyl pyrrolidone) to form a slurry. The grout also contained 0.50% bwoc of maltrodextrin, a cement settling retarder. The grout was mixed for 45 seconds in a high shear Waring blade mixer. The grout was divided into two samples. One sample was exposed to 4.3 Mrad of gamma radiation from a Co-60 source, while the other was kept as a control. The control sample that was not irradiated was still fluid, with a performance point measured at 150 Pa, while the gamma-irradiated sample was crosslinked and completely solid.

Example 4

800 grams of a Class H cement was mixed with 320 mL of water (w / c = 0.40) and 0.5% 900,000 MW PEO (polyethylene oxide) bwoc to form a slurry. The grout also contained 0.50% bwoc of maltrodextrin, a cement settling retarder. The grout was mixed for 45 seconds in a high shear Waring blade mixer. The suspensions were exposed to gamma radiation doses ranging from 0.4 Mrad to 2.5 Mrad. All grout samples exposed to gamma radiation

<img file="MX338668B_D0080.tif" />

INSTITUTO MEXICANO DE LA PROPIEDAD INDUSTRIAL gave rise to gelation of the samples, while the control samples were maintained as a fluid with a yield point of 36 Pa.

Figure 2 illustrates the results of the PEO dose response study of the delayed radiation exposure. Figures 3 and 4 illustrate the results of the PEO dose response study, the delayed radiation exposure and the resulting effect on the Storage Module and the Loss Module. Modulus values ​​increased with radiation dose.

Example 5

The aqueous solutions of PEO and polycarboxylates were irradiated with 4.3 Mrads of gamma radiation. The observations are shown in Table 5.

Table 5

<td>ID Shows</td><td>Shows</td><td>Effect of Radiation</td>

<td> 1</td><td>2% 100,000 MW PEO solution</td><td>Crosslinks</td>

<td> 2</td><td>5% 100,000 MW PEO solution</td><td>Crosslinks</td>

<td> 3</td><td>2% 900,000 MW PEO solution</td><td>Crosslinks</td>

<td> 4</td><td>5% 900,000 MW PEO solution</td><td>Crosslinks</td>

<td> 5</td><td>10% ADVA 575 solution</td><td>No Crosslinks</td>

<td> 6</td><td>10% Melflux 1641 solution</td><td>No Crosslinks</td>

<img file="MX338668B_D0081.tif" />

Example 6

Two samples of cement grout were prepared by mixing: 150 grams of Class H cement; 60 grams of water (w / c = 0.40); 1.0% 900,000 bwoc of a PEO MW (polyethylene oxide); 0.50% bwoc of maltodextrin (settling retarder); 0.50% bwoc of HR-25 (settling retarder); 0.50% diutane rubber bwoc (rheology modifier). The grout was mixed for 45 seconds in a Waring blade mixer, according to the API mixing program. Mix # 1 was used as a control without an oxygen scavenger or scavenger, while mix # 2 contained an oxygen scavenger or scavenger (SnCI2), at a concentration of 0.14% bwoc. Each mix was divided into two sets of jars. A set of vials of each mixture was exposed to neutron irradiation, at a flow of 1 x 10¹¹n / cm²/ sec., for 2 minutes, while the other set of vials was kept as a control. Exposing the flasks to neutron irradiation causes the cement to settle. Gel resistance measurements were taken on the samples using the reverse extrusion rheology device and the results are listed in Table 5.

<img file="MX338668B_D0082.tif" />

<img file="MX338668B_D0083.tif" />

MEXICAN INSTITUTE OF PROPERTY

INDUSTRIAL

<img file="MX338668B_D0084.tif" />

Table 5

<td># Mixture</td><td>O2 Eliminator</td><td>Concentration (% bwoc)</td><td>Resistance Relative Gel (psi)</td>

<td> 1</td><td>None</td><td> 0,00</td><td> 17,5</td>

<td> 2</td><td>Sn Cl₂</td><td> 0,14</td><td> 58,5</td>

Example 7

Cement grouts were prepared using the procedure as in Example 6. Acrylamide (8% bwoc) and N, N'-methylene bis-acrylamide (0.5% bwoc) were used as polymer components instead of PEO. These slurries were exposed to neutron radiation at a flux of lxlO⁷n / cm²/ sec, for 20 minutes, while the other set of vials was kept as a control. Several different oxygen scavengers or scavengers were evaluated and the results are tabulated in Table 6.

Table 6

<td>O2 Eliminator</td><td>Concentration (% bwoc)</td><td>Resistance Relative Gel (psi)</td>

<td>None</td><td></td><td> 11,2</td>

<td>SnCl₂</td><td> 0,100</td><td> 297,4</td>

<td>SnClz</td><td> 0,200</td><td> 380,1</td>

<img file="MX338668B_D0085.tif" />

iri

J NS 7: “h '7 Ο l · · *. F 'i U' · NOT THE PROPERTY

<td>SnSO₄</td><td> 0,113</td><td> 222, 1</td>

<td>SnSO₄</td><td> 0,226</td><td> 146,1</td>

Example 8

Cement grouts were prepared using the procedure as in Example 6. Acrylamide (8% bwoc) and N, N'-methylene bis-acrylamide (0.5% bwoc) were used as polymer components instead of PEO. These slurries were exposed to neutron radiation at a flux of lxlO⁷n / cm²/ sec, for 20 minutes, while the other set of vials was kept as a control. Several different oxygen scavengers or scavengers were evaluated and the results are tabulated in Table 7.

Table 7

<td>O2 Eliminator</td><td>Concentration (% bwoc)</td><td>Resistance Relative Gel (psi)</td>

<td>None</td><td></td><td> 11,2</td>

<td>SnCl₂</td><td> 0,100</td><td> 385,7</td>

<td>Chloride hydroxyl phosphonium tetrakis</td><td> 0,100</td><td> 443,9</td>

<td>Sulfoxialte formaldehyde sodium</td><td> 0, 100</td><td> 402,4</td>

<img file="MX338668B_D0086.tif" />

<td>Dioxide</td><td> 0, 100</td><td>, IhUiUSTRlAI. . 316.1</td><td></td>

<td>thiourea</td><td></td><td></td><td></td>

<td>Diotionito de</td><td> 0,100</td><td> 178,3</td><td></td>

<td>sodium</td><td></td><td></td><td></td>

Example 9

Two samples of cement grout were prepared by mixing: 200 grams of Class H cement; 80 grams of water (w / c = 0.40); 4.0% acrylamide bwoc; 4.0% N-vinyl pyrrolidone bwoc; 0.42% N'-methylene bisacrylamide bwoc (crosslinker), 0.50% maltodextrin bwoc (set retarder), 0.50% HR-25 bwoc (set retarder), 0.20% rubber bwoc diutane (rheology modifier); 2.0% SYLOID 900W bwoc (silica gel, commercially available in WR Grace &amp; Co.). The grout was mixed for 45 seconds in a Waring blade mixer, according to the API mixing program. Mix # 1 was used as a non-sensitizing control, while Mix # 2 contained sensitizer (SnClz) at a concentration of 0.10% bwoc. Each mix was divided into two sets of jars. One set of vials of each mixture was exposed to gamma radiation from a Co-60 source for 0-60 Gy, while the other set of vials was kept as a control. Exposing the vials to gamma radiation causes the cement to settle.

<img file="MX338668B_D0087.tif" />

Gel resistance measurements were taken on the samples using the reverse extrusion rheological device and the results are listed in Table 8. The addition of the sensitizer made a significant difference in the resistance of the obtained gel.

Table 8

<td>ftMix</td><td>Sensitizer</td><td>Concentration (% bwoc)</td><td>Dose Radiation (Gy)</td><td>Resistance BER Gel (psi)</td>

<td> 1</td><td>None</td><td> 0,0</td><td> 0</td><td> 0,1</td>

<td> 1</td><td>None</td><td> 0,0</td><td> 30</td><td> 0,3</td>

<td> 1</td><td>None</td><td>or or</td><td> 60</td><td> 3,3</td>

<td> 2</td><td>SnCl₂</td><td> 0,1</td><td> 0</td><td> 0,6</td>

<td> 2</td><td>SnCl₂</td><td> 0,1</td><td> 30</td><td> 80, 6</td>

<td> 2</td><td>SnCl₂</td><td> 0,1</td><td> 60</td><td> 199,4</td>

Example 10

Cement grouts were prepared using the procedure described in Example 9. Acrylamide (8% bwoc) and N, N'-methylene bis-acrylamide (0.5% bwoc) were used as polymer components. SYLOID RAD 2005 Silica, with a surface treated with 20% organic instead of 900W Syloid, both commercially available from WR Grace &amp; Co.

MEXICAN INSTITUTE

OE LA PHOPIECAU V ^ raSSíL, ^ industrial -25- ^ ¾¾. ^

The mixtures were treated and tested as in Example 9, the results are shown in Table 9,

Table 9

<td>#Mixture</td><td>Sensitizer</td><td>Concentration (% bwoc)</td><td>Dose Radiation (Gy)</td><td>Resistance BER Gel (psi)</td>

<td> 1</td><td>None</td><td>OR or</td><td> 0</td><td> 0,0</td>

<td> 1</td><td>None</td><td> 0,0</td><td> 30</td><td> 0,0</td>

<td> 1</td><td>None</td><td> 0,0</td><td> 60</td><td> 0,0</td>

<td> 2</td><td>SnCl₂</td><td> 0,1</td><td> 0</td><td> 0,7</td>

<td> 2</td><td>SnCl₂</td><td> 0,1</td><td> 30</td><td> 147,1</td>

<td> 2</td><td>SnCl₂</td><td> 0,1</td><td> 60</td><td> 325, 7</td>

Example 11

Two samples of silica flour were prepared by mixing 200 grams of silica flour; 66 grams of 0.18% Ca (OH) 2 solution; 4.0% acrylamide bwoc; 4.0% bwoc of

<td></td><td>N-vinyl-pyrrolidone; 0.42% bwoc acrylamide N, N'-methylene</td><td>Bis</td>

<td> 10</td><td>(crosslinker); 0.50% bwoc of maltodextrin (retarder</td><td>of the</td>

<td></td><td>settlement); 0.20% diutane rubber bwoc (modifier</td><td>of</td>

<td></td><td>rheology). The grout was mixed for 45 seconds in</td><td>a</td>

Waring blade mixer, according to API mixing program. Mix # 1 was used as a non-sensitizing control, while Mix # 2 contained sensitizer (SnCl2) at a concentration of 0.10% bwoc.

ÍιΜΙ INSTITUTE OF THE PÍIOPK OAD

INDUSTRIAL

<img file="MX338668B_D0088.tif" />

Each mix was divided into two sets of jars. One set of vials of each mixture was exposed to gamma radiation from a Co-60 source for 0-60 Gy, while the other set of vials was kept as a control. Exposing the vials to gamma radiation causes the cement to settle. Gel resistance measurements were taken on the samples using the reverse extrusion rheological device and the results are listed in Table 10. The addition of the sensitizer made a significant difference in the resistance of the gel obtained.

Table 10

<td>#Mixture</td><td>Sensitizer</td><td>Concentration (% bwoc)</td><td>Dose Radiation (Gy)</td><td>Resistance BER Gel (psi)</td>

<td> 1</td><td>None</td><td> 0,0</td><td> 0</td><td> 0,0</td>

<td> 1</td><td>None</td><td> 0,0</td><td> 30</td><td> 0,0</td>

<td> 1</td><td>None</td><td> 0,0</td><td> 60</td><td> 0,0</td>

<td> 2</td><td>SnCl₂</td><td> 0,1</td><td> 0</td><td> 0,6</td>

<td> 2</td><td>SnClz</td><td> 0,1</td><td> 30</td><td> 37,5</td>

<td> 2</td><td>SnCl₂</td><td> 0,1</td><td> 60</td><td> 87,1</td>

Example 12

1Μ1? ΙΌ&gt;

‘^NSTí ^ reo? uDÁo ^D industrial

Two samples of grout are prepared by mixing the following: Mix 1 had 325 grams of Class H cement; 130 grams of water (w / c = 0.40); 0.50% bwoc of maltodextrin (settling retarder) and 0.50% bwoc of HR-25 (settling retarder). Mix 2 had 325 grams of silica flour and 143 grams of 0.18% Ca (OH) 2 water solution (w / c = 0.44, to provide alkaline media). For each mixture the following was added: 8.0% acrylamide bwoc; 0.50% bwoc N, N'-methylene bis-acrylamide (crosslinker);

0.20% diutane rubber bwoc (rheology modifier) ​​and

0.10% bwoc SnCl2 (sensitizer).

The two grouts were prepared in different proportions of solids to maintain the rheology of the two similar grouts. The grouts were mixed for 45 seconds in a Waring blade mixer, according to the API mixing program. Each mix was divided into two sets of jars. One set of vials of each mixture was exposed to gamma radiation from a Co-60 source for 0-60 Gy, while the other set of vials was kept as a control. Exposure of the vials to gamma radiation causes the cement to settle. Gel resistance measurements were taken on the samples using the reverse extrusion rheological device and the results are listed in Table 11. The addition of the

<img file="MX338668B_D0089.tif" />

INSTITUTE ΛC / .NO DE L / λ íROrJcDAD

INDUSTRIAL sensitizer made a difference resistance of the gel obtained.

significant

<img file="MX338668B_D0090.tif" />

Table 11

<td>Radiation Dose</td><td>Mix 1</td><td>Mix 2</td>

<td>(Gy)</td><td>Gel resistance</td><td>Gel resistance</td>

<td></td><td>(psi)</td><td>(psi)</td>

<td> 0</td><td> 0,4</td><td> 0,9</td>

<td> 15</td><td> 0, 3</td><td> 187,7</td>

<td> 30</td><td> 0,9</td><td> 437,4</td>

<td> 60</td><td> 28,1</td><td> 402</td>

<td> 120</td><td> 111,0</td><td> 704,8</td>

<td> 180</td><td> 213, 6</td><td> 596,8</td>

<td> 240</td><td> 300,2</td><td> 627,9</td>

<td> 300</td><td> 312,4</td><td> 652,6</td>

<td> 360</td><td> 266, 5</td><td> 686, 4</td>

Example 13

Four grout samples were prepared by mixing the different binders in different water-solids ratios to produce similar rheology. The recipes for the mixes are shown in Table 12.

Table 12

<td colspan="4"></td><td></td>

<td></td><td>Mix # l</td><td>Mix # 2</td><td>one Mix # 3</td><td>ü £ LA i κ O r; £ i ?, ». 3 ' MezóldW</td>

<td>Binder</td><td>Micro-sand</td><td>Flour</td><td>Cement·-</td><td>- Ce-n · ..........</td>

<td></td><td>APS = 5üm</td><td>Silica</td><td></td><td>Steering wheels: Cement</td>

<td></td><td></td><td>(SSA-1)</td><td></td><td> (1:1)</td>

<td></td><td></td><td>APS = 17üüm</td><td></td><td></td>

<td>Quantity</td><td> 150</td><td> 150</td><td> 150</td><td> 150</td>

<td>Binder</td><td></td><td></td><td></td><td></td>

<td>w / s</td><td> 0,55</td><td> 0,55</td><td> 0,40</td><td> 0,40</td>

<td>Retardant</td><td>None</td><td>None</td><td>1% bwoc</td><td>1% bwoc</td>

<td>(HR: MD, 1: 1)</td><td></td><td></td><td></td><td></td>

<td>Diutane rubber</td><td> 0, 0</td><td> 0,32</td><td> 0,20</td><td> 0,20</td>

<td>(VMA)</td><td></td><td></td><td></td><td></td>

<td>Acrylamide</td><td>8.08% bwos</td><td>8.08% bwos</td><td>8.08% bwos</td><td>8.08% bwos</td>

<td>Bisaorilamide</td><td>0.43% bwos</td><td>0.43% bwos</td><td>0.4 3% bwos</td><td>0.43% bwos</td>

<td>Methylene</td><td></td><td></td><td></td><td></td>

<td>SnCl₂</td><td>0.10% bwos</td><td>0.10% bwos</td><td>0.10% bwos</td><td>0.10% bwos</td>

The suspensions were prepared in different water: solids ratio to maintain the rheology of the similar grouts. The grouts were mixed for 45 seconds in a Waring blade mixer, according to the API mixing program. Each mix was divided into two sets of jars. One set of vials of each mixture was exposed to gamma radiation from a Co-60 source for 0-120 Gy, while the other set of vials was kept as a control. The causes resistance device are listed

Λ Ρ T

I saw i '1

UTO MEXlCAN '.

THE PRCPJEiTAL INDUSTRIA!

exposure of the vials to gamma radiation

-////)

MEXICAN INSTITUTE

Dt THE PRCP, 'Ei? AD V INDUSTRIAL cement settlement. Measurements of the gel were taken on the samples using the reverse extrusion rheology and the results in Table 13.

Table 13

<td>Dose</td><td>Mix 1</td><td>Mix 2</td><td>Mix 3</td><td>Mix 4</td>

<td>Radiation</td><td>Resistance</td><td>Resistance</td><td>Resistance</td><td>Resistance</td>

<td>(Gy)</td><td>Gel (psi)</td><td>Gel (psi)</td><td>Gel (psi)</td><td>Gel (psi)</td>

<td> 0</td><td> 0, 6</td><td> 0,1</td><td> 0,4</td><td> 0,4</td>

<td> 15</td><td> 52,4</td><td> 0,1</td><td>ND</td><td> 11, 5</td>

<td> 30</td><td>ND</td><td> 26</td><td> 0,4</td><td> 79, 6</td>

<td> 45</td><td> 183, 0</td><td> 72,4</td><td>ND</td><td> 113,6</td>

<td> 60</td><td> 238,4</td><td> 86,7</td><td> 19, 4</td><td> 166, 9</td>

<td> 90</td><td> 320,0</td><td> 163,2</td><td>ND</td><td> 185, 6</td>

<td> 120</td><td> 446,5</td><td> 258,8</td><td>ND</td><td> 284,7</td>

The data in Table 13 is shown in Figure 8.

Example 14

Five polymers were chosen for a series of comparative tests. The polymers were polymethyl methacrylate (PMMA), polyhexylsulfone, cellulose acetate, cellulose butyrate acetate, and polymethylacrylonitrile. Polymers were dissolved in appropriate solvents and thin films

ΙΜΡΪί

INSTITUTO ΜΕ.Τ.CaXO

OF THE

INDUSTRIAL rotatably covered on a glass slide. The thickness of the films ranged from 0.5 µm to 2 Qm. The slides were subjected to different treatments as follows: (a) They were immersed in saturated Ca (0H) 2 solution to test the alkaline stability of the polymer films. This served as the control; (b) They were immersed in saturated Ca (OH) 2 solution and exposed to radiation from

<img file="MX338668B_D0091.tif" />

<td></td><td>neutrons; (c)</td><td>Same</td><td>what B) ,</td><td>but with nanoparticles</td><td>of</td>

<td></td><td>UNCLE2, (d) Same</td><td colspan="3">than (b) but with TÍO2 nanoparticles,</td><td>than</td>

<td> 10</td><td>contain ions</td><td>Faith³⁺ (to</td><td>from</td><td>ferric nitrate).</td><td></td>

<td></td><td>Samples (b)</td><td>to</td><td>(d) is</td><td>exposed to irradiation</td><td>with</td>

neutrons in a flux of 10¹² n / cm²/ sec, for 20 minutes.

The results are tabulated in Table 14.

Table 14

<td>Polymer</td><td>Treatment</td><td>Appearance</td>

<td>PMMA</td><td>Control</td><td>Intact</td>

<td></td><td>Radiated</td><td>Intact</td>

<td></td><td>Radiated with UNCLE2</td><td>Intact</td>

<td></td><td>Radiated with UNCLE2 + Faith³⁺</td><td>Intact</td>

<td>Polyhexylsulfone</td><td>Control</td><td>Cloudy</td>

<td></td><td>Radiated</td><td>Degradation Partial</td>

<td></td><td>T1O2 radiated</td><td>Degradation</td>

<td></td><td></td><td>INDUSTRIAL Partial</td>

<td></td><td>T1O2 + radiated Faith³⁺</td><td>Degradation Partial</td>

<td>Cellulose Acetate</td><td>Control</td><td>Intact</td>

<td></td><td>Radiated</td><td>Intact</td>

<td></td><td>T1O2 radiated</td><td>Total degradation</td>

<td></td><td>Radiated with UNCLE2 + Faith³⁺</td><td>Separates under N2 flows while dry</td>

<td>Butyrate Acetate Cellulose</td><td>Control</td><td>Intact</td>

<td></td><td>Radiated</td><td>Intact</td>

<td></td><td>T1O2 radiated</td><td>Shrugged movie</td>

<td></td><td>T1O2 + radiated Faith³⁺</td><td>Degradation Partial</td>

<td>Polymethyl acrylonitrile</td><td>Control</td><td>Intact</td>

<td></td><td>Radiated</td><td>Degradation Partial</td>

<td></td><td>Radiated with UNCLE2</td><td>Degradation Partial</td>

<td></td><td>T1O2 + radiated Faith³⁺</td><td>Degradation Partial</td>

100

ΙΜ

Pl

<img file="MX338668B_D0092.tif" />

The term accelerator can include any of, lr&gt; «a. components that reduce the settling time of a cement composition. For example, the accelerator can include alkali and alkaline earth metal salts, such as a calcium salt. The calcium salt can include calcium formate, calcium nitrate, calcium nitrite, or calcium chloride.

The term cement composition, as used herein, includes pastes (or grouts), mortars, and sets, such as oil well cementitious sets, shotcrete, and concrete compositions having a hydraulic cement binder. The terms pasta¹', mortar and concrete are terms of art: Pastes are mixtures composed of a hydratable (or hydraulic) cement binder, (generally, but not exclusively, Portland cement, masonry cement, cement mortar and / or plaster and may also include limestone, hydrated lime, fly ash, blast furnace slag, and silica fume (or other materials commonly included in such cements) and water; mortars are pastes that additionally include fine aggregate (eg sand) and concretes are mortars that additionally include coarse aggregate (eg crushed rock or gravel). The cement compositions described in this invention are formed by mixing required amounts of certain

101

Λ Á Ρ Τ: 1-1. .1 Λ * • Vi MEXICANO \ * ΡΒ &lt;· ΙΒι C Γ. λ ΤΙ

·. ·&gt;; Mexican - ü PRüf'tEDAD INPUST! LAL

<img file="MX338668B_D0093.tif" />

materials, for example, hydraulic cement, water and coarse and / or fine aggregate, as may be necessary for the manufacture of a particular cementitious composition.

As used herein, comb polymers refers to those polymers that have a main chain central axis and pendant groups of linear side chains.

The term encapsulating layer, as used herein, can mean any form of coating or in which most of the bond of material being encapsulated is enclosed within the layer and that the dissipation of matter is limited substantially by the layer. This does not mean that all of the material being encapsulated is enclosed within the layer or that the material being encapsulated cannot leak through the encapsulating layer.

The term ionizing radiation or radiation can be referred to as induction ionization or indirectly ionizing, which are capable of detaching electrons from atoms or molecules and can include alpha rays, beta rays, gamma rays, proton rays, neutron radiation, protons, X-rays and UV rays.

The term oxidizing agent or oxidizing agent can include any component that is capable of degrading the retarder present. These include, but are not limited to, alkaline earth and zinc salts of peroxide, perphosphate, perborate,

102

ΙΜΓ

<img file="MX338668B_D0094.tif" />

INDUSTRIAL percarbonate, calcium peroxide, calcium phosphate,

T, calcium perborate dihydrate acid, magnesium peroxide, magnesiumphosphate, zincphosphate; calcium hypochlorite, magnesium hypochlorite, chloramine trichloroisocyanuric, trichloromelamine, dichloroisocinaurate, anhydrous dichloroisocinaurate and mixtures thereof.

As used herein, polycarboxylate comb superplasticizers means those dispersing polymers and copolymers of cement, having a polycarboxylate backbone and pendant polyalkylene oxide groups, such as polyethylene oxide, polypropylene oxide, etc. and mixtures thereof. Polymers of these general types can be prepared in any suitable manner, such as, for example, by unsaturated copolymerization of unsaturated (meth) acrylic mono (alkoxy) polyalkylene glycol or monomer type ester with (meth) acrylic acid type monomers, such as described in the USA Pat. N⁰ 6,139,623, the disclosure of which is incorporated herein by reference.

The term polymeric additive, as used herein, can include one or more than one polymer or polymer precursor, such as a monomer or intermediate prepolymer, that is susceptible to ionizing radiation. The term radiation tolerance, as used in this

103 document, is the amount of ionizing radiation that a

Τ Μ Ρ Τ

λ.αρ -.-'-., λ? ad industrial material can withstand no appreciable or measurable degradation. The term settling retarder or retarder can include hourly or non-hourly forms of phosphonic acid, phosphonic acid derivatives, lignosulfonates, salts, sugars, carbohydrate compounds, organic acids, carboxymethylated hydroxyethylated celluloses, synthetic co- or ter-polymers that they include sulfonate and carboxylic acid groups and / or borate compounds.

The term settling as used in the present work, refers to an increase in the mechanical resistance of a wellhead treatment fluid or slurry, sufficient to carry out a desired result, such as to restrict the movement of an element or impede the flow of fluid or the transfer of pressure through a fluid. A cement can be referred to as set forth when the movement of a tube can be restricted or the transfer of pressure prevented by fluid flow, regardless of whether the cement has cured to a fully solid composition. A wellhead treatment fluid or slurry may be referred to as settling when it has thickened to a level sufficient to achieve the desired result, such as isolation of a particular area or restriction of fluid flow or pressure transfer, regardless of whether you have

104

ΙΜΡΪ

INSTITUTO MFXiCANO íTt- ~ -ST7. A PROPERTY reached its final consistency. The term '^ wellhead treatment fluid may be CUarqUTST ΓΤΠΓ &lt;3δ ”ο suitable grout for wellhead operations, drilling, completion, repair or production operations such as cement, drilling mud adjustable, loss of circulation fluids, fracturing fluids, conformity fluids, sealants, resins, etc., and combinations thereof.

Depending on the context, all references to the invention, in some cases, may refer only to certain specific embodiments. In other cases, it may refer to the subject matter recited in one or more, but not necessarily, all claims. Although the foregoing is directed to representations, versions and examples of the present invention, which are included to enable a person of ordinary skill in the art to make and use the inventions when the information in this patent is combined with the available information and technology. , the inventions are not limited only to these exemplary embodiments. Others and other particular versions, representations, versions and examples of the invention can be devised without departing from the basic scope thereof and the scope thereof is determined by the following claims. Although the compositions and methods are described in terms of which comprises containing or

II

105

IM ΡI

INSTITUTO MEXICa.NO DE LA VROP.EUaD including various components or steps, the provisions and methods may also consist of that component consisting of the various components and steps. All the numbers and ranges disclosed above may vary by some amount. Each time a numerical range with a lower limit and an upper limit is disclosed, any number and any range included falls within the range that is specifically described. In particular, each range of values ​​(in the form, from approximately a to approximately bo equivalently, from approximately a to bo equivalently, from approximately ab) described in this document is to be understood as having established each number and range encompassed within the widest range of values. Furthermore, the conditions in the claims have their plain, ordinary meaning, unless explicitly stated otherwise and clearly defined by the patent owner.

106

IMPI

MFXCaNC INSTITUTE · PROPERTY PROPERTY

IN OU 3 TRL \ L