Fluid distribution system

ES 2 394 869 T3

DESCRIPTION

Fluid distribution system

The present invention relates to a system for the distribution of a fluid according to the preamble of claim 1.

In a known tube-type irrigation system, a plurality of tubes with many holes directed upward at an angle, through which the acid is discharged radially, extend from a main distribution tube. By means of baffle plates fixed to the tubes, these jets are directed downwards into the compact bed.

Such systems are used, for example, for the countercurrent absorption of SO3 or water vapor in sulfuric acid in a packed rectification tower. At the top, for example, of a cylindrical container, the absorbent acid is distributed evenly across the cross section of the apparatus by means of an irrigation system and drips through a compact bed from top to bottom. From the gas flowing countercurrently to the top, the dripping acid absorbs the SO3, correspondingly increasing the acid concentration, or water, thereby diluting the acid. In standard configurations, the absorber constitutes a filling rectification tower built as a counter-flow apparatus, the casing of which is divided into three zones: the lower part is formed by the sump with the acid outlet, the middle part contains, for example, the packed bed onto a support grid through which acid drips down, which is evenly distributed by an irrigation system located at the top of the bed. The acid inlet of the irrigation system and the gas outlet are located above the packed bed. Known problems with such systems are the reduced gas outlet area, which results in an unwanted local increase in gas velocity and therefore promotes entrainment of acid droplets or vapors.

From document US 2004/0182013 A1 a distributor system is known, in which the fluid is discharged without pressure from a plurality of openings in the side wall of the distribution hopper open at the top and is guided to a lower edge of dripping by means of a mesh structure curved laterally downwards, in which the mesh structure is passed through a distribution channel that forms a regulator. On the one hand, this device involves the problem of entrainment of fine acid droplets or vapors, and on the other hand the individual distribution members consisting of the distribution hopper and the mesh structure have an undesirably high space requirement, which results in a reduction in the area available for gas flow.

From US 5,906,773 A a liquid distribution system is known, in which the liquid is guided from a distribution hopper, which includes in a wall two openings arranged one above the other at a distance and leading to the inside a vertical guide tube, on an inclined deflector surface 5 on which an overflow is formed which should promote further distribution of the liquid. Then, the liquid flows through a vertical guide plate 7 on the surface of the filler filler material. In addition to the space requirement of these distribution members, there is also the problem of entrainment of liquid droplets or vapors.

A similar configuration of a counter flow column is disclosed in US 6,575,437 B2, in which the liquid is passed over the filler as a film and without pressure by means of a baffle plate arranged laterally with respect to a distribution hopper.

In the distribution tubes known from US 5,439,620 A, the liquid exits the openings in the upper surface thereof and flows through guide surfaces provided laterally in the distribution tubes, which have a dripping edge. in saw teeth, up to the surface of the filler. The desired uniform distribution of the liquid along the length of the distribution tubes is not positively guaranteed. Another problem here is exact pressure control to avoid liquid splashing from the opening.

Document WO 02/083260 A discloses a system according to the preamble of claim 1. A liquid dispenser for use in a mass transfer column has a mass transfer bed located in an internal region open on the inside. of the column. The liquid distributor is provided with charging hoppers, which supply the liquid stream to a plurality of elongated hoppers that are spaced apart and extend through the column in a parallel relationship. A plurality of holes are provided in the floor and in the side walls of the loading hopper to supply liquid to the hoppers. The hoppers are arranged below the loading hopper, and perpendicular to it.

WO 01/89655 A discloses a liquid distribution body for columns, which exchanges substances and heat. The liquid distribution body comprises several channels that are distributed over the cross section of the column and can be loaded with the liquid to be distributed. The liquid distributor in a column comprises a central conduit and several bypass conduits distributed through said column. Bypass ducts have holes in their side walls, through which tubes are inserted. During their operation, the liquid fluid leaves the central conduit into said bypass conduits and through the

ES 2 394 869 T3 tubes and bounces against the deflection elements. The liquid then flows downward into a filler.

The conduit, the bypass conduits and the deflection element are provided perpendicular to each other, so that the free area available for gas flow is necessarily reduced.

US 2001/0028121 A1 is directed to a flow distributor for distributing liquid over a packed bed of a process column. The dispenser includes a centrally disposed elongated loading hopper having hoppers disposed below said loading hopper and extending in a direction through the column which again is perpendicular to the longitudinal direction of said loading hopper. The side walls of said hoppers each have a plurality of holes through which liquid can be discharged. The liquid distributor comprises drain pipes attached to the side walls of the hoppers, which significantly exceed the width of the hopper.

Document EP 1 323 467 A1 discloses a device for an exchange of material and / or energy in a washing column. The individual fabric meshes comprise vertical yarns that are guided upward out of the mesh arrangement. These wires are bent at the ends and suspended in the associated distribution channel. This distribution mechanism is located on the external side walls of the distribution channel, thus exceeding the width of this distribution member in the horizontal direction.

Therefore, an object of the present invention is to allow a more efficient flow of the countercurrent flowing gas. In addition, a fairly uniform distribution of the fluid throughout the cross section of the filler will be achieved with little construction effort while minimizing the amount of fluid droplets or vapor entrained with the gas flow.

According to the present invention there is provided a system for dispensing a fluid comprising the features of claim 1.

In this way, it is achieved that the fluid droplets or vapors produced when the fluid exits the nozzles are trapped in the substantially closed distribution channel and do not pass into the gas phase. As a result, the gas flow rate can be increased, and therefore the diameter of the tower can be reduced, resulting in cost savings. A non-uniform discharge of fluid from the nozzles is compensated for by the level of fluid formed in the distribution channel and by the guide member joining it along the entire length of the distribution member. As a result, a uniform controlled flowable film is guided over the filler material. The distribution channel is attached downwardly to the distribution element and its width does not significantly exceed the diameter of the distribution element. In this way, the free area at the fluid inlet of the filling filler material is maximized for the passage of gas q₂It flows against the current. The specific acid input in proportion to the filler filler per m is up to 10 times, preferably between 2 and 3 times higher compared to other spray systems.

Preferably, the nozzles of the distribution member open downward into the distribution channel at an angle above the fluid level so that the fluid jets impinge on a side wall of the distribution channel. This promotes a more uniform supply of fluid along the length of the distribution channel.

To further avoid the generation of unwanted fluid particles or vapors, the guide member, which may constitute, for example, a guide plate, extends into the filler filler material, for example to a depth of approximately 100 mm.

For uniform fluid distribution by avoiding unwanted transfer of acid particles to the gas flow it is advantageous when the fluid level in the distribution channel is maintained between about 10 and 100 mm, preferably between about 15 and 80 mm, by above the outlet slot.

The width of the outlet groove of the distribution channel, for example, is between approximately 3 and 20 mm, preferably between approximately 5 and 15 mm.

The distribution elements used, several of which may be arranged at a mutual distance above the filler filler material, preferably have a diameter between about 30 and 300 mm, more preferably between about 50 and 250 mm.

In practice, the operating conditions are preferably chosen such that there is an excess pressure between about 20 and 60 kPa, preferably between about 50 and 100 kPa in the distribution element.

According to the invention, a ventilation device can be provided in the chamber of the distribution channel, to avoid an unwanted increase in pressure and a splashing of fluid out of the outlet slot.

It is also advantageous when the distribution channel is tapered downwards.

ES 2 394 869 T3

The system of the invention can be used, for example, in a reactor, in which fluid drips onto a filler material.

Further objectives, features, advantages and possible applications of the invention can be taken from the following description of an embodiment and the drawing. All the features described and / or illustrated form the subject matter of the invention per se or in any combination, also independently of their inclusion in individual claims or in the referenced documents.

Fig. 1 schematically shows, by way of example, a vertical section of a fluid distributor arranged above a filling filler material, consisting of a distribution member, a distribution channel and a guide member , several of which can be arranged at a mutual and parallel distance from each other to form a complete sprinkler system according to the invention.

Fig. 2 schematically shows a plan view of a filling rectification tower with the fluid distributor according to the invention.

The fluid distributor shown in the drawing includes a distribution member 1 constituting a pressure tubular conduit, which is preferably arranged parallel to the surface of a filler material PA. The fluid to be distributed over the filler material PA must be supplied to the distribution member 1, such that there is an excess pressure in it between approximately 20 and 60 kPa, preferably between approximately 40 and 400 kPa.

Without an increase in cross section, a distribution channel 2 joins the distribution member 1 in a downward direction. At its lower tapered end 4, the distribution channel 2 has an outlet gap 3 that extends substantially along its entire length for fluid accumulating in the distribution channel 2 to a level FP, which by means of nozzles 6 distributed along the length of the distribution member 1 is sprayed inside a closed chamber 7 formed above the fluid level FP and is defined by it and by the walls of the distribution channel and the distribution member. The system is operated in such a way that the fluid level FP is maintained between a maximum value FPmax (for example, approximately 100 mm) and a minimum value FPmin (for example, approximately 20 mm).

The nozzles 6 are arranged at an angle, so that the fluid jet first strikes a side wall of the distribution channel 2. The fluid droplets or vapors formed cannot be transferred to the countercurrent gas, but are trapped in the fluid level and therefore inside the chamber 7. In the figure, a direction of the nozzles is shown as an example; of course, the nozzles can also be directed to the other side wall. An alternate position of nozzles or double nozzles in different directions is also possible. Also, the nozzles need not be radially arranged, but may be tangentially arranged or may point in other directions.

In chamber 7, a pressure is maintained which roughly corresponds to the pressure in the packed rectification tower. By means of the constructional configuration and the pressure conditions it can be ensured that a uniform fluid film exits from the outlet gap 3 and an undesired overflow of the filler filler PA is prevented. With its lower end, the plate-shaped guide member 5 which is attached below the outlet gap 3 reaches into the interior of the filling filler material PA up to about 100 mm, for example, so that it is also avoided in this point an unwanted formation of fluid droplets or vapors.

In practical operation, the FP level of fluid can be, for example, between about 10 and 100 mm, preferably between about 20 and 70 mm, preferably between about 20 and 70 mm, the width of the outlet gap 3 can be between about 3 and 20 mm, preferably between about 8 and 10 mm, and the diameter of the distribution member 1 may be between about 30 and 300 mm, preferably between about 50 and 250 mm.

To maintain the desired pressure in chamber 7, it can be equipped with a ventilation device and in particular preferably with an overflow conduit, so that pressure cannot build up when too much fluid is supplied.

The chamber or its side walls may be configured differently from Figure 1, without departing from the idea of ​​the invention itself, specifically the discharge of a fairly slightly altered flow of fluid from the chamber and passing the fluid flow compact enough to load materials.

In particular, the walls can have a symmetrical, tapered, straight or special shape. Also, the guide member 5 need not project vertically in the plane of the loading material, but can also be inclined. Furthermore, it is possible to use not one, but a plurality of outlet recesses and in particular also a plurality of guide members, pointing in different directions.

Also, the outlet gap need not be inclined, but may be open in particular directly downwardly or laterally.

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As shown in Fig. 2 by way of example, a plurality, here four, of distribution members 1 are provided side by side above the filler PA, to evenly distribute the fluid over the entire cross-section of the tower. Sulfuric acid is supplied to the distribution members 1 via a common supply conduit 8.

In a particular aspect of the invention, the nozzles 6 may not have any uniform diameter or shape, but rather different diameters depending on the distance from the supply conduit.

List of reference numbers distribution member outlet hollow distribution channel tapered end guide member nozzles chamber supply conduit

FP fluid level

PA filler