MXPA00002382A - Apparatus for collecting and distributing liquids in a column - Google Patents

Abstract

Device for collecting and distributing liquids in a column comprises a laminar collector (200) with a distributor outlet system (300) arranged underneath. A subsidiary channel (210) is arranged in each collector, and liquid outlets (214, 216,and 332) are arranged in a combination on the basis of which a hydrodynamic comparison for a liquid to be distributed is produced.

Description

APPARATUS FOR COLLECTION AND DISTRIBUTION OF LIQUID IN A COLUMN DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for the collection and distribution of liquid in a column. In this, a plurality of unordered or ordered packages are located in the column as in each case on a carrier grid, below which an apparatus for the collection and distribution of liquid is placed. In material exchange columns of this kind, the packing or the filling body is supported by a carrier grid, where the liquid drips on this carrier grid and is captured, mixed and conducted to a new distribution or redistribution, respectively, or for liquid removal. The field of application is preferably a material separation technique such as absorption and desorption in fluid systems, distillation and rectification and the technical realization of reactions in catalyst layers. For several years it has been usual to use unsorted or packaged filler bodies, in particular packaged structured or ordered respectively, in material exchange columns. Its effectiveness depends very strongly on the uniform wetting of its surface with reverse flow or backflow and without observing a mass ratio of liquid-vapor which is equal to the cross section. In case of a non-uniform liquid outlet and a resulting non-uniform distribution and wetting, maldistribution (failed distribution) occurs within the layers of the filling body, for example in the form of a passage flow. This considerably restricts the effectiveness and function of the exchange column. For this reason a liquid distributor is placed above the packaging station which is designed to distribute the fluid flowing down as evenly as possible over the cross section of the column. Many collectors and distributors for liquids are known which try with more or less cost and complexity to obtain a uniform distribution of liquid required in the described columns of exchange of material. Distributors of this kind are, for example, known from the article by P. Bomio et al., Chem. Tech., Vol. 43, no. 11/12, 1991 and are here designated as pipe distributors, element distributors or passenger distributors. These types of liquid distributors have horizontally oriented distributor passages which are fed by at least one main passage, which as a rule extends perpendicularly to the distributing passages. In a tube distributor, the distributor passages are closed on the upper side; in an element distributor or passage distributor are open above. The elements I distributors or the passenger dealers operate with a certain level of filling in the tickets. The hydrostatic pressure which is connected to them regulates the amount of liquid which drips through the special discharge elements on the packing section that is under them. The fill height increases approximately to the square of the liquid load. Since the passages cover a large portion of the cross section of the column, a distributor of this kind contains large amounts of liquid of a specific composition. This affects the inertia of the distributor! and therefore to the whole column with respect to rapid changes in the composition of the liquid distributed. J The description of the operating principles of | These well-known collectors and distributors also illustrate their disadvantages to the same extent. ¡The liquid that flows out of this packing section is collected and collected by a liquid collector. The liquid is transported out of the liquid collector into a main passageway or to the lateral passages of the distributor via a tube or shaft construction. The feeding takes place via a relatively large inflow, generally central I, or a plurality of relatively large inflows.

The turbulences and flow velocities that result from this method of construction are very large in the distribution flows of this class. Therefore, suitable means such as a predistributing passage or an inflow painkiller should be installed in the main passage. The transfer of the liquid takes place in a stage or in a plurality of stages in a closed or open design, however always so that the liquid flows following the gravity. In this, the problem arises insofar as there is no uniform distribution of the liquid by the flow in the longitudinal direction of the distributing passages. Depending on how far affluent liquid and liquid effluent are separated from each other in a passageway, the effluent opening flows through liquid with different effluent velocity. It has also been recognized that the weak points of the material exchange column with respect to rapid load changes are found in liquid collectors and liquid distributors. Particularly important are the distributors and collectors which are placed between packing sections and which are designed to provide as uniform a backflushing liquid distribution as possible over the cross section of the column. For example, a long time is required until a new steady state is obtained, along with a higher or lower fill level in the distributors. This cause is observed in that the concentration of large liquid volumes must be changed before a new steady state is established. In addition, it should be noted that the above apparatuses to join and complete the mixing of the entire backflushing liquid after it has been captured in the collector and the subsequent multiple new distribution or redistribution upwards and including the fine distribution and the points of dripping are very complicated and expensive construction. The thick distribution of multiple caps frequently used for the entire backflushing fluid through inflows, main passages and lateral passages contains many sources of poor fluid distribution. The sources of error are, for example, non-uniform flow conduction through continuous accelerations and decelerations of the liquid and insufficient leveling during assembly. In known apparatuses, large geodetic height differences are required to accelerate and decelerate sufficiently large volumes of liquid a plurality of times. Through this, the construction height of the known apparatus is relatively large. In addition, the apparatus for a coarse distribution causes a lack of strong uniformity for the gas or steam flow respectively, which has an influence on the efficiency of the entire column. Based on the prior art, it is further known that one can supply with facilities for the intentional mixing of down-dripping and captured liquid in order to reduce the construction height of the material exchange columns. An apparatus for the collection and redistribution of liquid according to the preamble of the invention is described in US 5464573. The apparatus described herein is provided with facilities for the intentional mixing of the captured liquid with the decisive disadvantage that in case from a non-uniform distribution of the liquid, an equalization of the liquid and the flow connected with it come in the horizontal plane. The effects described before turbulence in the distribution of the liquid in the conventional distributors are increased more through the simple saving in the collection and predistribution stages and the result is an effluent of non-uniform liquid from the distributor. The object of the invention is how to develop an apparatus for collecting and distributing liquid gas in material exchange columns which allows a very homogeneous liquid outlet on a column cross section with a low construction height and which also allows a Rapid adaptation to load changes during operation.

An apparatus according to the invention is designed so that the liquid collector, the gas or steam distributor respectively and the gas or steam distributor respectively and the liquid distributor are combined together in an apparatus. The backflushing liquid which is captured by a collector which is modified according to the invention is not intentionally placed together and is intensively mixed for the purpose of an equalization of the composition but rather it has surprisingly been found that the purpose of the invention is satisfied insofar as the liquid is distributed directly in the collector to a non-uniform degree such that the hydrodynamic equalization is performed with a small difference in geodetic height. A hydrodynamic equalization is present when, in the similarly spaced apart liquid outlet openings, the direction, velocity and surface level of the flowing liquid are equalized by being placed above them. The intensity of the equalization flows and the quantity of the liquid which participates in the hydrodynamic equalization is influenced by the poor hydrodynamic distribution at the end of the packing section which is located above the collector and distributor apparatus. The collector and distributor apparatus has flow dividers which convey the horizontal equalization flows in such a way that they can not exert influence that alters the new distribution of the backflushing liquid. The apparatus is designed in such a way that the liquid preferably flows directly from the collection position to the nearest dripping point without a low flow rate. As the essential advantages of the invention, it is possible to mention the very homogeneous fluid dynamic fluid outlet with a high distribution quality which is obtained by means of the reduction of unnecessary flow turbulences and a high density of drip location that is generated with a height of small construction. The equalization of flows requires much less than the flows in previous collection and distribution constructions. In addition, the content of the stationary liquid (retention) is reduced compared to a conventional collector and distributor apparatus by a smaller number of distributor stages and the transport of the horizontal liquid is strongly reduced. Therefore, smaller passage widths can be obtained for the distributing passages. An improvement in the load change compartment is caused by the shorter idle time of the liquid in the collector and distributor apparatus and through the reduction of the stationary fluid content.

It is also advantageous to reduce the total weight of the apparatus and to reduce the cost and complexity of the assembly compared to conventional collector and distributor units. Instead of a reduction of the construction height of the column, the number of subsequent separating stages in the existing columns can be increased when the possibility of installing additional packages after the replacement of the conventional manifold and distributor with the novel one is used. , according to the invention. In the following the invention will be described as well as additional details with greater definition, with reference to exemplary embodiments which are illustrated in the drawings. In these the following is shown: Figure 1 is a schematic illustration of the previous method of constructing a packing column with a separate collector and distributor apparatus, Figure 2 is a schematic illustration of a packing column with a collector and distributor apparatus according to the invention, figure 3 is a perspective view from the top on a redistribution station according to the invention, consisting of liquid collectors and distributors, partially explodedFigure 4 is an exemplary embodiment of a further development according to the invention of a collector-distributor apparatus in a graphic illustration, figures 5 a / b / c are different examples of execution of the main and lateral passages of harvesting lamellae, Figure 6 is an exemplary embodiment of an affluent soothing in an enlarged view, Figure 7 is an exemplary embodiment for a distributor effluent system. In Figure 1, a conventional redistribution station 10 is illustrated in schematic illustration. In this, the column ramp 12, the upper packing bed 14, the lower packing bed 16 and the redistribution stations are placed between them, as can be seen. The latter consists of a collecting apparatus 20 and a completely separate dispensing apparatus 30. The liquid is transported from the collection apparatus 20 to the main central entrance of the predistributor 32 or the distributor 34 through at least one downward and downwardly extending downwardly directed tube 26. The liquid is then evenly distributed over the lower packing bed 16 with the aid of at least one distribution stage. Figure 2 is a schematic illustration of a redistribution station 100 with a compact collector and distributor apparatus 123 according to the invention. The illustration comprises the column ramp 12, as in Figure 1, and a bed 14 and 16 of upper and lower packing. The reduction in space between the upper and lower packing bed compared to FIG. 1 is clearly recognizable. Figure 3 shows sections of the compact collector-distributor apparatus 123, which is comprised of a lamella collector 200 with integrated lateral passages 210 and a distributor effluent system 300 positioned below it, preferably with a ring passage 340. The main passages 202 of the lamella collector 200 are placed horizontally parallel to each other and vary in length so that they reach the ramp of the column. The so-called lamella 204 and the lamella collector 200 are thin metal sheets which are angularly bent or fixed in deflection of the vertical column axis at the upper edge of the main passages 202. Its projected area covers almost the cross-sectional area of the free column between the main passages 202 and thus convey liquid which drips from the upper packing bed 14 into the interior of the main passages of the collector. The lamellas 204 are bent and a small amount descending at an inclination at the upper end and leading a portion of the collected liquid to the adjacent main passage. Each main collector passage 200 contains a flow divider 212, for example in the form of a sheet or metal sheet section, with hydraulically defined openings and with an inclined or horizontal section. This flow divider 212 is a constituent of the lateral passage 210 and separates the latter from the main passage. The affluent of the liquid from the main passage 202 to the lateral passage 210 takes place by means of the openings 214 of hydraulically defined liquid effluent. The liquid deviates from the side passages 210 by means of the openings 216 of hydraulically defined liquid effluent and enters the interior of the dispensing effluent system 300. When the quantities of the liquid which are transported out of the different lateral passages 210 differ, a hydrodynamic equalization also takes place in the passages 330 distributors. Preferably, a ring passage 340 may be placed in such a manner that all the passages 330 are connected to one another by means of the same. The liquid flows and then distributed evenly according to the principle of the communicating tubes. The passages 330 distributors have a discharge system which has openings 332 hydraulically defined liquid effluents. The liquid is evenly distributed over the lower packing bed through these openings 332 of liquid effluents. The lamella collector 200 is separated from the lateral passage 210 by a flow divider 212. By a flow divider is meant here a construction which divides in the middle part, which flows in one direction in two partial flows with different direction, for example, in a flow which continues to be horizontal and one with a vertical directional component. The flow divider 212 is preferably positioned such that during operation it is located below the surface of the liquid which has been previously picked up and then allowed to stand or flow in the corresponding main passage 202. Produces a flow resistance in the vertical direction. Through this, two cross sections of flow arise. In the upper one, the main passage 200, the liquid is transported horizontally and in the lower passage, the lateral passage 210, a flow arises in the direction of the liquid effluent openings 216 alone. The reduction of the horizontal flow velocity which is caused by maldistribution directly above the liquid effluent opening 216 causes a significant improvement of the distribution quality. Figure 4 shows the section of a different compact collector-distributor apparatus 123, which is assembled from a class of lamella collector with integrated lateral passages 210 and with a ring passage 240 as well as a dispenser effluent system 300 which is placed under it. The main passages 202 of the lamella collector 200 are placed horizontally parallel to each other and vary in length so that they reach the ring passage 240 which is placed on the inner side of the column ramp. All the main passages 202 of the collector in this way are connected to the ring passage 240 and are connected to each other in this manner. The ring passage 240 allows the equalization of liquid amounts in all of the major 202 passages to a level. Figures 5a / b / c show enlarged modalities of the main passage 202, the flow divider 212 and the lateral passage 210. The liquid exiting the side passage 210 via other liquid effluent openings 210 hydraulically defined. The liquid effluent openings 216 can be implemented as conventional base holes 216a, as simple side holes 216b or as side holes with drainage pipes 216c (see Figure 5c). They transport the liquid inside the open distributor effluent system which is placed below it. The construction elements between the liquid effluent openings 216 and the distributor effluent system however are advantageous but not necessarily inflow pads 302 (see also Figure 6). They prevent undesirable strong flow turbulences from arising through the affluent in the liquid in the distributor passage. The affluent painkillers 302 are placed directly below the liquid effluent openings 216 of the side passage 210. Figure 6 shows in detail an exemplary embodiment for a tributary calmer 302. It consists of a thin-walled dip tube 304 with a preferably circular cross-section, the inner diameter of which is larger than the liquid effluent opening of the side passage which is located above it. The dip tube 304 protrudes, for example, 50 to 90% of its length L304 into a thin-walled container 306. The diameter D306 of the container 306 is greater than the diameter of the immersion tube 304 by a factor of at least -i 2, preferably not greater than half the width of the passage D330. The container 306 is open upwards; its base 308 is closed; its sheath surface 310 is designed to be completely closed or perforated only in the upper edge region. A screen grid 312 and / or a guide sheet grid 314 can be placed between the dip tube 304 and the container 306. The liquid enters the interior of the dip tube 304 and from there into the interior of the container 306. The base 308 forces the fluid that flows down to reverse its direction. Through the sieve grid 312, large turbulences are divided into small ones, which decay more rapidly. The liquid flow which is directed upwards afterwards is almost similar to a well flow which is relatively weak and uniform. A guide sheet grid 314 is useful for uniform orientation of the liquid flow. The liquid then flows shallowly on the edge of the container 306 inside the distributor passage 330.

Figure 7 shows a section of an exemplary embodiment for a distributor effluent system 300. Illustrated is a thin-wall dispenser passage 300 with tubes 334 positioned inwardly and a vertically positioned guard 336, which serves as a flow divider and divides the distributor passage 330 into almost two chambers. The liquid enters from the lateral passage or the affluent soothing into the interior of the first chamber with the width B1. The latter is formed by the weir 336 and, for example, the right side wall of the distributor passage 330. In this region, the liquid can also be distributed uniformly horizontally and then flows through a hydraulically defined opening with the height H in the second chamber, with the width B2 for the tubes 334. The tubes 334 have openings 332 of liquid effluent through which the liquid flows out of the packed bed and is placed under it.

Claims (15)

1. An apparatus for the collection and distribution of liquid in a column, comprising at least one lamella collector and a distributor effluent system which is placed below it, with a lateral passage contained within or within each lamella collector and liquid effluent openings that are placed in a combination, as a result of which a hydrodynamic equalization is obtained for a liquid to be distributed.

2. The apparatus as described in claim 1, characterized in that in the lamella collector a flow divider separates a main passage from a lateral passage; and wherein the liquid effluent openings are partially introduced into the flow divider.

3. The apparatus as described in claim 2, characterized in that the lamella collector together with the main passage and the lateral passage as well as the flow divider form a unit which is constructed of an aerial material through surface elements which they are placed angularly between them.

4. The apparatus as described in claim 2, characterized in that the flow divider is designed in such a way that the liquid enters the interior of the lateral passage and takes place outside the main passage from the top or from below through the openings of effluent of liquid.

5. The apparatus as described in any of claims 1 to 4, characterized in that a plurality of lamella collectors placed parallel to each other cover the entire cross-sectional area of a material exchange column.

6. The apparatus as described in any of claims 1 to 4, characterized in that the plurality of main passages of the lamella collectors are connected together by a ring passage of the collector.

7. The apparatus as described in any of claims 1 to 4, characterized in that the outlet of the liquid out of the lateral passage within the distributor effluent system takes place via a tributary painkiller.

8. The apparatus as described in any of claims 1 to 4, characterized in that the liquid outlet out of the lateral passage opens into a chamber of the distributor effluent system which is located between a side wall of the effluent distributor system and a landfill .

9. The apparatus as described in claim 7, characterized in that the affluent quencher is constructed of a dip tube which is centrally placed in a vessel, with the cross-section of the dip tube being larger than the outlet opening. of liquid from the lateral passage that is above it.

10. The apparatus as described in claim 7, characterized in that the dip tube projects 50 to 90% of its length in a thin-walled container.

11. The apparatus as described in claim 9, characterized in that the cross-sectional area of the container is at least twice as large as the cross-sectional area of the dip tube.

12. The apparatus as described in claim 9, characterized in that with a circular cross section of the dip tube and the container, the diameter of the container is greater than the diameter of the dip tube by a factor of at least -I2 and is preferably no more than half the width of the passage.

13. The apparatus as described in claim 9, characterized in that the container has a lower base and is open upwards.

14. The apparatus as described in claim 9, characterized in that a screen grid is placed over the entire cross-sectional area of the container or only between the dip tube and the container.

15. The apparatus as described in claim 9 and 10, characterized in that the guide knife grid is positioned at least between the overlap of the container and the dip tube.