Defoamer formulation and methods for making and using same.

foamed downhole fluid systems.

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Patent TITLE no. 337458

Institute

Mexican Property

Industrial

Holders): LUBRIZOL OILFIELD SOLUTIONS, INC,

Address: 29400 Lakeland Blvd., Wickliffe, Ohio, 44092, USA

Name: AN ANTI-FOAM FORMULATION AND METHODS OF PREPARATION AND USE OF THE SAME.

Classification:

Inventor!

lnt.CI.8: B01D19 / 04; C09K8 / 02; C09K8 / 42; C09K8 / 62

OLUSEGUN MATTHEW FALANA; EDWARD C. MARSHALL; FRANK ZAMORA

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Sand! No. 550, Floor 1,

Co!. Santa Maria Tepepan Town

Xochimilco. CP 16020,

Mexico City

Tei. (55) 53 34 07 00 www ñnpígob.mx

MX / 2016/18336

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AN ANTI-FOAM FORMULATION AND METHODS OF PREPARATION AND USE

OF THE SAME

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FIELD OF THE INVENTION

The embodiments of this invention relate to a defoamer for use in recyclable foam systems for use in all downhole operations including drilling, fracturing, completion, cementing, stimulation, and / or enhancement, where the defoamer has consistent activity. throughout all downhole operations making the defoamer universal.

More particularly, the embodiments of this invention relate to a universal defoamer for use in foaming systems for, use in all downhole operations including drilling, fracturing, completion, cementing, 'stimulation, and / or enhancement operations, where the antifoam includes a combination of Silicon-based antifoam agents at concentrations with effective and efficient antifoam potency characteristics.

BACKGROUND OF THE INVENTION

Systems of drilling fluids, fracturing fluids, completion fluids, cementing, stimulation fluids are often designed to produce foams with

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INSTITUTO MEXICANO characteristics suitable for drilling operations or related operations. The capacity of-.....

reusing the systems is' always advantageous to reduce chemical use and also the management as a global economy of an operation. Despite the obvious advantages, a large number of drilling systems cannot be reused or recycled, due to the lack of adequate defoamer systems that allow foam-removal and re-foam cycles. Although some known defoamers allow reuse of fluid systems, they are not environmentally benign.

In the prior art, the primary objective was always to formulate a suitable system to meet the end use conditions. End use conditions such as temperature, pH, salinity, contaminants, base fluid and so on are examples. Once a suitable system has been formulated, recyclability · as much as is desirable for example, is a secondary consideration. Thus, there are many fluid systems that are for one-step operations, and only a few are recyclable.

Although there are many defoamers and defoamer systems, there is a continuing need in the art for defoamers and defoamer systems that have consistent performance properties across all

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INSTITUTO MEXICANO os LA PROPERTY operations downhole and all systems esp) tiñiiafl4ie ^ * ^ rJ ^^{to go}fluids, especially at low concentrations, at 200ppm7-- · —— while maintaining the ability of foaming systems to re-foam or undergo various foam-defoam-re-foam cycles.

SUMMARY OF THE INVENTION

The embodiments of the antifoam compositions of this invention include on a volume basis between about 40% volume and about 80% volume of distilled water (other types of waters may be used instead), between about 10% volume and about 30% volume of silicon antifoam agent and between about 10% volume and about 30% volume of silicon antifoam active agent, where the composition is stable at temperatures up to around 232.2 ° C (450 ° F) and is effective at a concentration less than or equal to 500 ppm in all foamed fluids used in downhole applications. Foamed fluids include foamed drilling fluids, foamed completion fluids, foamed fracturing fluids, foamed stimulation fluids, foamed cements, and / or other foamed fluids used in downhole operations.

The modalities of the methods of use of the

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antifoam compositions of this industry add an effective amount of an antifoam composition of this invention to a foamed fluid, where the amount is sufficient to result in a clean breakdown of the foamed fluid, where the antifoam composition includes on a volume basis between about 40 % volume and about 80% volume of distilled water (other types of water can be used instead), between about 10% volume and about 30% volume of silicon antifoam agent and between about 10% volume and about 30% volume of silicon antifoam active agent and where the effective amount is an amount of the composition antifoam less than or equal to about 500 ppm regardless of the type of fluid foamed and where the antifoam composition is stable at temperatures up to about 232.2 ° C (450 ° F) and where the antifoam composition allows continuous repeated foam-antifoam cycles, generally with the addition of additional foaming composition.

DETAILED DESCRIPTION OF THE INVENTION

Definitions of the terms used in the invention

The following definitions are provided to assist those skilled in the art in understanding the

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detailed description of the present Mexican invention

OF INDUSTRIAL PROPERTY

The term fracture refers to the process and methods of breaking a geological formation, that is, the formation of rock around a drilling well, when pumping fluid at very high pressures, in order to increase the production flows of a reservoir of hydrocarbons. The fracturing methods of this invention use conventional techniques otherwise known in the art.

The term "surfactant" refers to a soluble, or partially soluble compound that reduces the surface tension of liquids, or reduces the interfacial tension between two liquids, or a liquid and a solid by coming together and orienting themselves at these interfaces.

The term drilling fluids refers to any fluid that is used during oil and / or gas well drilling operations.

The term completion fluids refers to any fluid that is used in oil and / or gas well completion operations.

The term production fluids refers to any fluid that is used in oil and / or gas well production operations.

A drilling fluid with administered pressure and / or

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underbalanced means a fluid of perf oracior? * 'q ^ Ñ'dKce circulating hydrostatic density (p ration.) less ^ or equal to a formation density (pressure). For example, if a known formation at 3,048 m (10,000 ft) (Depth

Total Vertical - TVD) has a hydrostatic pressure of 351.53 kg / cm² (5,000 psi) or 1.15 kg / lt (9.6 lb / gal), an underbalanced drilling fluid would have a hydrostatic pressure less than or equal to 1.15 kg / lt (9.6 lb / gal). Most underbalanced and / or pressure administered drilling fluids include at least one density reducing additive. Many other additives include a corrosion inhibitor, a pH modifier, and a shale inhibitor.

The term foamable means a composition that when mixed with a gas forms a stable foam.

The term gpt means gallons per thousand gallons.

The term ppt means pounds per thousand gallons.

The inventors have found that antifoam compositions can be formulated to be universally efficient and effective in reducing foam from a wide variety of foamed fluid systems used in downhole operations, while retaining the ability to re-foam. The inventors have found that the antifoam compositions of this invention can be used mn + Bl

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MEXICAN INSTITUTE. . ,. . OF PROPERTY _ in low concentrations in these systems ιν ^ «βμαι. ± foamed to completely break the^,s ~ ^ sprrma'S '. ·' ··· ..... The inventors have also found the antifoam compositions of this invention to be environmentally benign.

In certain embodiments, the antifoam compositions of this invention include an effective amount of Silicon antifoam agent, such as Antifoam B available from 3M of St. Paul, MN, which comprises 60.0% by weight of water, 7.0-13.0% by weight of polydimethylsiloxane, and optionally 5.0% by weight of methylcellulose. In certain embodiments, the antifoam compositions of this invention include an effective amount of Silicon antifoam active agent, such as Antifoam 1410 available from Dow Corning, which comprises&gt; 60.0% by weight of water, 7.0-13.0% by weight of polydimethylsiloxane, 1-5% by weight of hydroxyethylcellulose, 1-5% by weight of amorphous treated silica, and 1-5% by weight of C14-C18 mono- and di-glycerides.

For the first time, the inventors have been able to develop an antifoam that is compatible with all foam systems known to the inventors. Not only do the antifoam compositions of this invention remove foam from a wide variety of fluid systems used in downhole operations, the antifoam compositions allow the foamed fluid system to be reused or subjected to foam-antifoam cycles and resurfacing. foam. Most of the known defoamers are alcohols, mixtures of alcohols, ethers, hydrocarbons, or other combinations thereof. Many of these defoamers are hazardous to the environment, although the defoamer compositions of this invention can be used without special handling and disposal requirements.

The antifoam compositions of this invention are effective and efficient at low concentrations less than or equal to about 200 ppm, whereas most of the more competitive antifoams are effective at a concentration greater than or equal to about 2,000 ppm. Therefore, the antifoam compositions of this invention are more cost efficient than other well known antifoams currently used on the market.

The antifoam compositions of this invention have been tested successfully in the field. The antifoam compositions of this invention can be formulated into untreated chemical compositions. The inventors have found that the antifoam compositions of this invention combine several unique aspects that are superior to the antifoams described in the prior art. The antifoam compositions of this invention are thermally stable up to 232.2 ° C (450 ° F), they are

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Environmentally benign, they are robust in their Cc ^ SW to remove foam from various foam systems or different operating conditions, while preserving the use of foam systems - they retain the ability of foam systems to undergo repeated foam-antifoam cycles. new foaming.

The antifoam compositions of this invention have efficient and effective antifoam properties even at low concentrations and are compatible with additives for drilling fluids, additives for completion fluids, additives for fracturing fluids, cementing additives and additives used in other downhole operations. that use foaming systems. The antifoam compositions of this invention are also more accessible than many other currently known antifoam systems. The antifoam composition of this invention allows repeated foam-foam removal cycles, where the number of foam-foam removal cycles is at least 2. In other embodiments, the number of foam-foam removal cycles is at least 5. In other embodiments, the number of foam-foam removal cycles is at least 5. In In other modalities, the number of foam-antifoam cycles is at least 10.

Drilling fluids

In general, foamed drilling fluids are used

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while drilling a well. Fluids ™ or drilling can be designed for underbalanced drilling (a hydrostatic pressure of the drilling fluid is less than the pore pressure of the formation) or drilling with managed pressure, where the hydrostatic pressure of the drilling fluid is managed depending on the nature of the material through which the drilling occurs and is generally foamed to reduce the hydrostatic pressure of the drilling fluid relative to the hydrostatic pressure of the formation to reduce the penetration of the fluid into the formation.

The antifoam compositions of this invention are designed to defoam such low concentration drilling fluids, even drilling fluids operating at temperatures up to 232.2 ° C (450 ° F).

Embodiments of the present invention relate to the use of the antifoam compositions of this invention to defoam foamed drilling fluids, wherein an effective amount of an antifoam composition of this invention is added to the foamed drilling fluid to break up the foam. The antifoam compositions of this invention include aqueous solutions of Silicon-based antifoams. Suitable defoamers are

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DC THE PROPERTY ϊι ”ν exemplified by Antifoam B and Antifoam 1410 ^INwhat are available from Dow Corning. The amount of antifoam composition is sufficient to break the foam or reduce the foam height to zero or close to zero (where near means within 5% of the foam height zero). ). In certain embodiments, the effective amount is less than or equal to about 200 ppm.

Termination fluids

Modalities of the present invention relate to reducing foam or breaking foamed termination fluids, where the foamed termination fluids remove the foam with the addition of an effective amount of one of the antifoam compositions of this invention, where the effective amount is less than or equal to about

200 ppm.

Fracture fluids

Embodiments of the present invention relate to the use of the antifoam compositions of this invention to reduce the foam of foamed fracture fluids, wherein the foamed fracture fluids remove foam with the addition of an effective amount of the antifoam compositions of this invention, where the effective amount

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IMPI is less than or equal to additional over around 200 ppm.

INSTITUTO MEXICANO ΓΛ-BTi DE LA PROPERTY industrial

For information on components of fracture fluids that are

<td></td><td>can use</td><td>with fluids</td><td>of fracture of this</td><td>invention the</td>

<td></td><td colspan="3">reader is referred to US patents</td><td>United Nos.</td>

<td> 5</td><td colspan="2"> 7140433, 7517447, 7268100,</td><td> 7392847, 7350579,</td><td>7712535, and</td>

<td></td><td>7565933; Y</td><td colspan="2">published requests from States</td><td>United Nos.</td>

<td></td><td> 20070032693,</td><td> 20050137114,</td><td> 20090250659,</td><td> 20050250666,</td>

<td></td><td> 20080039345,</td><td> 20060194700,</td><td> 20070173414,</td><td> 20070129257,</td>

<td></td><td> 20080257553,</td><td> 20090203553,</td><td> 20070173413,</td><td> 20080318812,</td>

<td> 10</td><td> 20080287325,</td><td> 20080314124,</td><td> 20080269082,</td><td> 20080197085,</td>

<td></td><td> 20080257554,</td><td> 20080251252,</td><td> 20090151959,</td><td> 20090200033,</td>

<td></td><td> 20090200027,</td><td> 20100000795,</td><td> 20100012901,</td><td> 20090067931,</td>

20080283242, 20100077938, 20100122815, and 20090275488. These applications and patents are incorporated by reference through the operation of the last paragraph of the specification.

Stimulation Fluids

Modalities of the present invention relate to the use of the antifoam compositions of this invention to reduce the foam of the foamed stimulation fluids, wherein the foamed stimulation fluids eliminate the foam with the addition of an effective amount of the antifoam compositions of this invention. , where the effective amount is less than or equal to about 200 ppm.

Composition Ranges

In certain modalities,

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Defoamers of this invention include on a volume basis between about 40% volume and about 80% volume distilled water (other types of waters may be used instead), between about 10% volume and about 30% volume of silicon antifoam agent and between about 10% volume and about 30% volume of silicon antifoam active agent.

In other embodiments, the antifoam compositions of this invention include on a volume basis between about% volume and about 80% volume distilled water (other types of waters may be used instead), between about 10% volume and about 25% volume of silicon antifoam agent and between about 10% volume and about 25% volume of silicon antifoam active agent. In other embodiments, the antifoam compositions of this invention include on a volume basis between about 60% volume and about 80% volume of distilled water (other types of waters may be used instead), between about 10% volume and about 20% volume of silicon antifoam agent and between about 10% volume and about% volume of silicon antifoam active agent. In

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In other embodiments, the antifoam compositions of this invention include on a volume basis between about% volume and about 70% volume distilled water (other types of waters may be used instead), between about 15% volume and about 25% volume of silicon antifoam agent and between about 15% volume and about 25% volume of silicon antifoam active agent. In certain embodiments, the silicon anti-foaming agent is Antifoam B available from Dow

Corning and silicon anti-foaming active agent is

Antifoam 1410 available from Dow Corning. The antifoam compositions are milky white liquids having a pH of about 7.03 and a specific gravity of about 0.997.

Foam Composition Ranges

In general, the amount of antifoam agent added to reduce the foam of well fluids made lighter is a volume% amount sufficient to break the foam. In one embodiment, the defoamer composition is used in ranges from about 0.05 volume% to about 5 volume%. In another embodiment, the antifoam composition is used in ranges from about 0.1% volume to about 2.5% volume. In another mode, * AUJL J • NWWOMtXK ^ o^DEW&lt;»¿?

the antifoam composition is used in certain ranges from about 0.1% volume to about 1.0 volume.

In another embodiment, the antifoam composition is used in ranges from about 0.25 volume% to about 0.5 volume%. In other embodiments, the antifoam composition is used in an effective amount less than or equal to

500 ppm. In other embodiments, the antifoam composition is used in an effective amount less than or equal to 400 ppm. In other embodiments, the antifoam composition is used in an effective amount of less than or equal to 300 ppm. In other embodiments, the antifoam composition is used in an effective amount less than or equal to 250 ppm. In other embodiments, the antifoam composition is used in an effective amount of less than or equal to 200 ppm.

Suitable Reagents

Suitable water-based antifoam reagents for use in the antifoam compositions of this invention include, without limitation, a mixture of Silicon agents having antifoam activity, where the mixtures include at least one polydimethylsiloxane and where the antifoam compositions are effective in a quantity less than or equal to around 200 ppm and stable at temperatures up to 232.2 ° C (450 ° F) and is universally applicable to all agents

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¹⁶ known sparklers. In certain it includes Antifoam B and Antifoam 1410.

modalities, the

Proper Drilling Fluid Components

Suitable water-based fluids include, but are not limited to

<td colspan="6">limitation, sea water, fresh water, saline water or a system</td>

<td>spare such</td><td>what</td><td>contain</td><td colspan="2">up around</td><td>30% off</td>

<td>Raw oil.</td><td></td><td></td><td></td><td></td><td></td>

<td>The agents</td><td>of</td><td>foamed</td><td>suitable</td><td>for</td><td>use in this</td>

The invention includes, without limitation, any foaming agents suitable for foaming water-based drilling fluids. Illustrative examples of foaming agents include, without limitation KleanFoam ™, DuraFoam ™, FMA-100 ™,

TransFoam ™ (all available from Weatherford International) or mix or combinations.

Suitable polymers for use in this invention include, without limitation, any water-based fluid soluble polymer. Exemplary polymers include, without limitation, a polymer comprising units of one or more (one, two, three, four, five, ..., as many as desired) polymerizable salts of mono-olefins or di-olefins. Illustrative examples include, without limitation, natural polymers (starch, hydroxymethyl cellulose, xanthan, guar, etc.) and derivatives; co-polymerizable monomers such as

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acrylates (acrylic acid, methyl acrylate, ethyl acrylate, etc.), methacrylates (methacrylic acid, methyl methacrylate, ethyl methacrylate, etc), 2-acrylamindomethylpropane 'sulfonic acid, vinyl acetate, acrylamide, or the like, of course provided that the resulting polymer is soluble in the water-based fluid,

Gases

Suitable gases for foaming the ionically coupled gel, foaming composition include, without limitation, nitrogen, carbon dioxide, or any other gas suitable for use in forming fractures, or mixtures or combinations thereof.

Corrosion inhibitors ₍

Corrosion inhibitors suitable for use in this invention include, without limitation: quaternary ammonium salts for example, chlorides, bromides, iodides, dimet hyl sulfates, diethyl sulfates, nitrites, bicarbonates, carbonates, hydroxides, alkoxides, or the like, or mixtures or combinations thereof; nitrogen base salts; or mixtures or combinations thereof. Exemplary quaternary ammonium salts include, without limitation,

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INSTITUTO MEXICANO oe la monedad ,.

&gt; N&gt; USTK | AL quaternary ammonium salts of an amine and a &lt;3e quaternizing agent, for example, alkyl chlorides, alkyl bromides, alkyl iodides, alkyl sulfates such as dimethyl sulfate, diethyl sulfate, etc. , dihalogenated allogens such as dichloroethane, dichloropropane, dichloroethyl ether, epichlorohydrin adducts of alcohols, ethoxylates, or the like; or mixtures or combinations thereof and an amine agent, for example, alkylpyridines, especially highly alkylated alkylpyridines, alkyl quinolines, C6 to C24 synthetic tertiary amines, amines derived from natural products such as cocci, or the like, dialkyl substituted methyl amines, amines derived from the reaction of fatty acids or oils and polyamines, DETA amidoimidazolines and fatty acids, ethylenediamine imidazolines, imidazolines. of diaminocyclohexane, aminoethylethylenediamine imidazolines, propane pyrimidine diamine and alkylated propylene diamine, mono- and oxyalkylated polyamines sufficient to convert all related hydrogen atoms in the amines to oxygen-containing groups, or the like or mixtures or combinations of the themselves. Illustrative nitrogen base salts include, without limitation, nitrogen base salts derived from a salt, for example: Cl to C8 carboxylic mono acids such as formic acid, acetic acid,

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INSTITUTO MEXICANO VííSw—

THE PROPERTY V * £. "'SShv?

• 'ndustwal propanoic acid, butanoic acid, pentanoic acid, acidb^-^ hexanoic, heptanoic acid, octanoic acid, Z- ~ ~ ethylhexanoic acid, or the like; dicarboxylic acids C2 a

C12, unsaturated carboxylic acids and C2 to C12 anhydrides, or the like; polyacids such as diglycolic acid, aspartic acid, citric acid, or the like; hydroxy acids such as lactic acid, itaconic acid, or the like;

aryl and hydroxy aryl acids; natural or synthetic amino acids; thioacids such as thioglycolic acid (TGA);

free acid forms of phosphoric acid, glycol derivatives, ethoxylates, ethoxylated amine, or the like, and aminosulfonic acids; or mixtures or combinations thereof and an amine, for example: high molecular weight fatty acid amines such as cocoamine, tallow amines, or the like; oxyalkylated fatty acid amines;

high molecular weight fatty acid polyamines (di, tri, tetra, or higher); oxyalkylated fatty acid polyamines; amino amides such as reaction products of carboxylic acid with polyamines where the equivalents of carboxylic acid are less than the equivalents of reactive amines and oxyalkylated derivatives thereof;

fatty acid pyrimidines; EDA monoimidazolines, DETA or higher ethylene amines, hexamethylene diamine (HMDA), tetramethylenediamine (TMDA), and higher analogs of the

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υ / Ίί: τ ·; το μ CELA * 3 same; bisimidazolines, imidazolines of polyorganic acids; oxázolines derived from monoethanol amine 'and fatty acids or oils, amines of fatty acid ethers, mono and bis amides of aminoethylpiperazine; GAA and TGA salts of the reaction products of crude oil by-product of cellulose plants (tall oil) or tall oil distilled with diethylene triamine; GAA and TGA salts of reaction products of dimeric acids with polyamine mixtures such as TMDA, HMDA and 1,2-diaminocyclohexane; imidazoline TGA salt derived from DETA with fatty acids from tall oil or soybean oil, cane oil, or the like; or mixtures or combinations thereof.

Other Additives

The drilling fluids of this invention may also include other additives such as scale inhibitors, carbon dioxide control additives, paraffin control additives, oxygen control additives, or other additives.

Scale Control

Suitable additives for scale control and useful in the compositions of this invention include, without limitation: chelating agents, eg, Na salts⁺, K⁺ or

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ΙΜΡ^Τ

INSTITUTO MEXICANO +,,, + OF THE PROPERTY

EDTA NH4; Na, K or NH4 salts of NTA; αβ salts^{, Ι, ι}ίΦ »“ 5

Erythorbic acid NHj; Na salts⁺, K⁺ or thioglycolic NH'Vde''aaccrdc (TGA); Na salts⁺, K⁺ or hydroxyacetic acid NH4; Na salts⁺, K⁺ or NH4 from citric acid; Na salts⁺, K⁺ or NH4 of tartaric acid or other similar salts or

<td>mixtures</td><td>0 combinations</td><td>of</td><td>the same.</td><td>Additives</td>

<td>suitable</td><td>who work</td><td>in</td><td>the effects</td><td>threshold,</td>

<td colspan="2">hijackers, include,</td><td>without</td><td>limitation:</td><td>phosphates, by</td>

<td>example,</td><td>hexamethylphosphate</td><td>of</td><td>sodium salts</td><td>linear of</td>

<td>potassium,</td><td>acid salts</td><td colspan="3">polyphosphoric, phosphonates, by</td>

<td>example,</td><td>non-ionic such</td><td colspan="2">as HEDP (acid</td><td>hydroxytylidene</td>

diphosphoric), PBTC (phosphoisobutane, tricarboxylic acid), amino phosphonates of: MEA (monoethanolamine), NH₃, EDA (ethylenediamine), Bishydroxyethylene diamine, bisaminoethyl ether, DETA (diethylenetriamine), HMDA (hexamethylene diamine), Hyper homologues and isomers of HMDA, Polyamines of

EDA and DETA, Diglycolamine and homologues, or similar polyamines or mixtures or combinations thereof; phosphate esters, for example polyphosphoric acid esters or phosphorus pentoxide esters (P₂OR₅) of: alkanol amines such as MEA,

DEA, triethanolamine (TEA), bishydroxyethylethylene diamine;

ethoxylated alcohols, glycerin, glycols such as EG (ethylene glycol), propylene glycol, butylene glycol, hexylene glycol, trimethylol propane, pentaerythritol, neopentyl glycol or the

<img file="MX337458B_D0025.tif" />

Similar;

Tris and Tetra hydroxy amines;

ethoxylated alkyl phenols (limited use due to toxicity problems), ethoxylated amines such as monoamines such as MDEA and higher amines of 2 to 24 carbon atoms, diamines of 24 carbon atoms, or the like; Polymers, for example, homopolymers of aspartic acid, soluble homopolymers of acrylic acid, copolymers of acrylic acid and methacrylic acid, terpolymers of acrylates, AMPS, etc., hydrolyzed polyacrylamides, polymeric anhydride (PMA); or the like; or mixtures or combinations thereof.

Carbon Dioxide Neutralization

Suitable additives for CO neutralization₂ and for use in the compositions of this invention include, without limitation, MEA, DEA, isopropylamine, cyclohexylamine, morpholine, diamines, 'dimethylaminopropylamine (DMAPA), ethylenediamine, methoxypropylamine (ΜΟΡΑ), dimethylethanolamine, methyldiethanolamine (MDEA) and oligomers, EDA imidazolines and higher homologues and adducts, aminoethylethanolamine imidazolines (AEEA), aminoethylpiperazine, aminoethylethanolamine, di-isopropanol amine, DOW AMP-90 ™,

Angus AMP-95, dialkylamines (methyl, ethyl, isopropyl), mono alkylamines (methyl, ethyl, isopropyl), trialkyl amines (methyl, ethyl, isopropyl), bishydroxyethylethylene diamine

<img file="MX337458B_D0026.tif" />

the like or mixtures or combinations^,'^,Aiof (THEED), or themselves.

Paraffin Control

Suitable additives for paraffin removal,

Paraffin crystal dispersion, and / or distribution include, without limitation: Cellosolves available from DOW

Chemicals Company; Cellosolve acetates; ketones; you come out of

Acetate and Eormiate; sur.factants composed of ethoxylated or propoxylated alcohols, alkyl phenols, and / or amines;

methyl esters such as coconate, laurate, soyate, or other naturally occurring methyl esters of fatty acids; sulfonated methyl esters such as sulfonated coconate, sulfonated laurate, sulfonated soyate or other naturally occurring sulfonated fatty acid methyl esters; low molecular weight quaternary ammonium chlorides from coconut oils, soybean oils or amines Cio to C₂4 o 'monohalogenated alkyl and aryl chlorides; quaternary ammonium salts composed of disubstituted chlorides (eg, dicoco, etc.) and halogenated alkyl and / or aryl chlorides of lower molecular weight;

Gemini type quaternary salts of dialkyl (methyl, ethyl, propyl, mixed, etc.) tertiary amines and ethanes, dihalogenated propanes, etc. or dihalogenated ethers such as ether of

<img file="MX337458B_D0027.tif" />

INSTITUTO MEXICANO dichloroethyl (DCEE), or the like; sales cud ^^ j ^^ íjjga

Gemini of alkyl amines or amidopropyl amines, ·. - -such. . „Jgomo_ cocoamidopropyldimethyl, bisquaternary ammonium salts of

DCEE; or mixtures or combinations thereof. Appropriate alcohols used in the preparation of the surfactants include, without limitation, linear or branched alcohols, especially mixtures of alcohols that react with ethylene oxide, propylene oxide, or a higher alkylene oxide, where the resulting surfactants have a range of HLBs. . Suitable alkylphenols used in the preparation of surfactants include, without limitation, nonylphenol, decylphenol, dodecylphenol, or other alkylphenols where the alkyl group has from about 4 to about 30 carbon atoms. Suitable amines used in the preparation of surfactants include, without limitation, ethylenediamine (EDA), diethylenetriamine (DETA), or other polyamines. Illustrative examples include Quadroles,

Tetrols, Pentrols available from BASF. Suitable alkanolamines include, without limitation, monoethanolamine (MEA), diethanolamine (DEA), reaction products of MEA and / or DEA with coconut oils and acids.

Oxygen Control

The introduction of water down the well is often accompanied

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INSTITUTO MEXICANO DE LA PROPERTY due to an increase in the oxygen content of 'Tos^RiA1Downhole due to dissolved oxygen in the introduced water

Thus, materials introduced downhole must work in oxygen environments or must work well enough until the oxygen content has been depleted by natural reactions. For systems that cannot tolerate oxygen, then oxygen must be withdrawn or controlled in some material introduced downhole. The problem is exacerbated during winter when the injected materials include antifreezes such as water, alcohols, glycols, Cellosolves, formates, acetates, or the like and because the oxygen solubility is higher up to a range of around 14-15 ppm. in very cold water. Oxygen can also increase corrosion and scale formation. In CCT (flexible capillary tubing) applications using dilute solutions, the injected solutions result in the injection of an oxidizing environment (O2) into a reducing environment (CO2, H2S, organic acids, etc.).

Options for controlling oxygen content include: (1) de-aeration of the fluid prior to downhole injection, (2) addition of normal sulfides to produce sulfur oxides, but such sulfur oxides can accelerate acid attack on the metal surfaces, (3) addition

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IMPI

INSTITUTO MEXICANO DE LA PROPIEDAD of erythorbates, ascorbates, diethylhydroxyamine or reactive oxygen compounds that are added to the fluid '' prior to injection. down the well; and (4) addition of corrosion inhibitors or metal passivating agents such as potassium (alkali) salts of glycol esters, ethyloxylates of polyhydric alcohols, or other similar corrosion inhibitors. Illustrative examples of oxygen and corrosion inhibiting agents include mixtures of tetramethylene diamines, hexamethylene diamines, 1,2-diaminecyclohexane, amine heads, or reaction products of such amines with partial molar equivalents of aldehydes. Other oxygen control agents include benzoic and salicylic amides of polyamines, used especially under alkaline conditions, short chain acetylene diols or similar compounds, phosphate esters, borate glycerols, urea and thiourea salts of bisoxalidines or other compound that already either absorb oxygen, react with oxygen, or otherwise reduce or eliminate oxygen.

Salt inhibitors

Suitable salt inhibitors for use in the fluids of this invention - include, without limitation, Na Minus

-Nitrilotriacetamide available from Clearwater International,

IMPI

MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY

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7

LLC of Houston, Texas.

Foam Characteristics

In general, foaming fluid systems will produce a foam that has a foam height of at least about 400 mL and a half-life of at least about 2 minutes. In particular, the foam produced will have a foam height between about at least 400 mL and about 800 mL and a half-life between about minutes and about 15 minutes or greater depending on the application and the exact formulation of the hydrocarbon fluid. of this invention. The stability or half-life and the height of the foam produced is controlled by the amount and type of the viscosity promoting agents in the composition, by the amount and type of the blowing agents in the composition, by the amount of gas and type of gas in the composition, by the temperature of the composition and by the pressure of the composition. In general, by increasing the amount of the viscosity promoting agents and / or foaming agents, the stability and height of the foam can be increased. In general, viscosity promoting agents increase stability more than foam height, while foaming agents increase foam height. Of course the height

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of the foam is also directly proportional to the amount and type of gas dissolved or absorbed in the fluid.

EXAMPLES

Example 1

This example illustrates the preparation of an antifoam composition of this invention designated DI.

L of distilled water were added to a clean reactor followed by the addition of 15 L of Antifoam B available from

Dow Corning. The resulting mixture was mixed thoroughly for 5 minutes. Then 15 L of Antifoam 1410 was added with continuous mixing for an additional 30 minutes to give the antifoam composition of this invention designated DI, which is a milky white liquid having a pH 7.03 and a specific gravity 0.997.

DI Properties

DI from Example 1 is a Silicon-based composition that includes a polydimethylsiloxane. DI is not dangerous and is not toxic to the environment. DI is effective as a defoamer at low treatment concentrations between 0.1% by weight and 2.0% by weight or as needed. DI allows foaming-antifoam-resurfacing cycles or allows all Weatherford foamers (WFT) to be recycled. DI is a less expensive defoamer than all

MEXICAN INSTITUTE ffl

OWNERSHIP other defoamers available from Weatherford.^INDUSTIüfÍ high thermal stability. DI has been found to be this "BTS" up to 232.2 ° C (450 ° F) in the laboratory as evident by the absence of any degradation (precipitation) or discoloration. DI defoamed foams have been shown to re-foam at a foaming capacity of the test system. Thus, DI is suitable for use under conditions hostile to conventional systems. DI is also compatible with Weatherford foam drilling additives.

Table 1 tabulates the DI breakdown or defoamer characteristics in a series of four Weatherford foaming systems: FMA ™ 100, KleanFoam ™,

DuraFoam ™ and TransFoam ™.

TABLE 1

Defoaming Properties of Di

<td>Water</td><td>Founder of foam</td><td>Foam former concentration (%)</td><td>DI concentration (%)</td><td>FH^to</td><td>R^b</td>

<td>Of the wrench</td><td>FMA ™ 100</td><td> 0.5</td><td> 0.8</td><td> 0</td><td>Yes</td>

<td>Of the wrench</td><td>KleanFoam ™</td><td> 0.5</td><td> 0.8</td><td> 0</td><td>Yes</td>

<td>Of the wrench</td><td>DuraFoam ™</td><td> 0.5</td><td> 1.0</td><td> 0</td><td>Yes</td>

<td>Of the wrench</td><td>TransFoam ™ 0</td><td> 0.5</td><td> 1.0</td><td> 0</td><td>Yes</td>

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• Foam height ^b Recyclable

The data in Table 1 clearly show that DI at levels of 1% by weight or less is an efficient and effective defoamer for all four foam systems of

Weatherford: FMA ™ 100, KleanFoam ™, DuraFoam ™ and TransFoam ™.

The data is unique in that this simple defoamer can defoam fluids including all three Weatherford foaming systems and that non-foaming fluids re-foam with the addition of additional foamer.

Corrosion data is tabulated in Table 2 for a drilling fluid that includes DI, OmniFoam ™, and CorrFoam ™! Corrosion inhibitor.

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TABLE 2

DI Compatibility with Drilling Fluid Additives

<td>ID of proof</td><td>Test Fluid</td><td></td><td>Time (days)</td><td>Run Kgn '² year¹(lbft²year¹)</td><td>Corrosion selective</td>

<td> 1</td><td>Tap^to + OFHT^b (2.0%) + DI (2.0%</td><td> )</td><td> 2</td><td> 36.296 (7.427)</td><td>Heavy</td>

<td> 2</td><td>Tap^to + OF^C (2.0%) + DI (2.0% CFl^d (0.5%)^and</td><td> ) +</td><td> 2</td><td> 0.973 (0.199)</td><td>Light</td>

<td> 3</td><td>SW^F (3.5%) + 0F^c (2.0%) (2.0%) + CFl^d (0.5%)^and</td><td>+ D1</td><td> 2</td><td> 13.957 (2.856)</td><td>Heavy</td>

<td> 4</td><td>SW^F (3.5%) + OF^C (2.0%) + (2.0%)</td><td>GAVE</td><td> 1</td><td> 12.520 (2.562)</td><td>Means, medium</td>

<td> 5</td><td>SW^F (3.5%) + OFHT^b (2.0%) (2.0%) + CFl^d (0.2%)</td><td>+ D1</td><td> 1</td><td> 2.028 (0.415)</td><td>Light</td>

<td> 6</td><td>SW^F (3.5%) + OF^C (2.0%) + (2.0%) + CFl^d (0.5%)</td><td>GAVE</td><td> 1</td><td> 3.866 (0.791)</td><td>None</td>

<td> 7</td><td>SW^F (3.5%) + OF^C (2.0%) DI (2. + CFl^d (0.2%)^and</td><td> 0%)</td><td> 1</td><td> 2.209 (0.452)</td><td>Light</td>

'Elmendorf tap water (containing about 71 ppm Ca ions'^!+, 21 ppm Na⁺ and 15 ppm of Mg²⁺) .

^b OmniFoam ™ HT is a thermally high salt stable foamer available from Weatherford International ^c OmniFoam ™ a stable saline skimmer available from Weatherford International ^d CF1 is CorrFoam ™ l, a corrosion inhibitor produced by Weatherford

International ^θ pH of fluid system adjusted to pH 10 f saline water

MEXICAN INSTITUTE

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The data in Table 2 makes evident the compatibility of DI in a fluid that includes OmniFoam ™ and CorrFoam ™ l corrosion inhibitor. The data is not only evident from acceptable levels of corrosion in systems containing DI, OmniFoam ™ foaming agent and inhibitor.

CorrFoam ™ l, but also the blends show evidence of an absence of degradation of any of the components at temperatures up to 250 ° F. In addition, minimal amounts of inhibitor are required for handling corrosion in freshwater fluids or surprisingly better in seawater based fluids. Tests ID 5 and 7 showed that pH adjustment is not necessary, saving cost of chemicals for pH adjustment.

All references cited herein are incorporated by reference. Although the invention has been described with reference to its preferred embodiments, from reading this description those skilled in the art can appreciate the changes and modifications that can be made that do not depart from the scope and spirit of the invention as stated. described above and claims to