DE10064632A1 - Mass- and energy exchange tower packing system comprising individual or bundled wires or threads, forms geometrically-defined network guiding counterflowing media - Google Patents

Abstract

The fluid guidance elements, e.g. wires (19), run in notional surfaces (21) essentially orientated at right angles. Seen in horizontal cross section they are straight line or otherwise, e.g. curved. The wires define flow channels (22) for the counterflowing medium between themselves. Preferred features: All parts of the packing slant from the horizontal. A mesh structure is formed, the wires running generally transversely or perpendicularly as bundles spreading between nodes (18), contacting individual adjacent wires. Spacing of wires, and mesh sizes, mitigate against film formation in the draining fluid. Wires form parallel perpendicular surfaces. Seen in cross section they provide long rectangular flow channels between themselves for the counterflowing medium. Wires of individual parallel surfaces are spaced by transverse elements connecting them to each other. Variant structures based on the foregoing principles are described. The wires are collected in groups at top and/or base of the tower, for liquid feed distribution and/or collection at the outlet, respectively. Multi-stage grouped construction is adopted. Wires are held in supply or drainage sockets. They are arranged in holding mandrels and passed through perforated plates with uniform slots and a system of holes of various radii with bushes for the bundles, resting on hole edges. Several proximate drain sockets are connected to a common predistributor. These are hung on universal joints. A diagonal braid is arranged on the inner wall of the tower or around the reaction packing.

Description

The invention relates to a device for generally vertical Flow guidance of a liquid to the substance and / or energy exchange in a trickle column according to the preamble of claim 1.

In the exchange elements for the substance and / or energy exchange in addition to the exchange floors used for centuries more and more Packing fillings offered to determine the separation performance Increase phase interface and instead usual for replacement floors Cross flow to use the more advantageous counterflow.

This goes hand in hand with an enlargement of the offered surface of the individual packing by reducing the packing itself. Because that Volume grows in the third power, while the area grows with the second grows, so that with the number of packing the surface offered elevated.

On the other hand, the packed bed becomes denser with less at the same time remaining free volume in the reaction space and an increase in Flow channels. This leads to an increase in the pressure loss (Δp / m) of the for example counter-flowing gas and thus to a larger one Energy exchange.

Through an improved shape of the packing and variability in the Materials have been tried to improve the separation effect. Because of the  flow conditions in packed beds were not manageable the structured packs are developed by side by side arranged plates are formed equal flow spaces.

For equal distribution of gas and liquid flows over the Pack cross section, the liquid must be on the offered exchange surfaces be evenly distributed and run evenly. It has however, it has been shown that it is practically impossible to keep liquids even to distribute on surfaces and let them run. You have through tried different surface designs or use of fabrics that To improve wetting, but that is the substance and / or energy exchange determining liquid film and thus the phase interface is not in Agreement with the exchange area offered.

This occurs with increasing surface area of the exchange elements, so that the specific surface required for the exchange more and more increases. This deterioration in the separating effect with exchange elements is used as a microscopic and macroscopic distribution (uneven distribution of the Phases).

So the well-known trickle film columns with bundles of plates could or pipes in which the phases carried in counterflow are unimpeded flow past each other, do not bring the desired increase in performance. Because there is a radial distribution in the separate flow spaces and mixing of the liquid in the packs themselves is no longer possible is the liquid feed at the top of the trickle column for the Determining separation effect.

Now it is particularly difficult to spread liquids evenly on a large Distribute number of plates or pipes. It also happens because of Surface tension of the liquids for dewetting and trickling  different running speeds and therefore stronger Deterioration of the separating effect.

In summary, this means that they differ only slightly from each other structured packings that distinguish their performance of the disadvantageous surface structure are limited in their application and so the known for centuries, albeit in recent decades improved, floor constructions for economic reasons could displace.

Taking into account the state of the art and basic research the area of material and / or energy exchange as well as the interests of Engineering technology is the objective of this invention, more powerful Exchange elements for a more economical use in the chemical and related industries.

Contrary to previous considerations, improvements in the To achieve separation effect / unit length (NTSM), it was recognized that it is for Throughput and thus production increases is more advantageous, low loss Exchange elements with the lowest possible pressure loss / length unit (Δp / m) to develop.

After through the patent application DE 100 24 142 and DE 100 51 523 Ways to distribute fluids evenly to any number Point of application of a cross-sectional area is an optimal one fluid dynamic dimensioning of the exchange elements possible.

A parallel reaction pack is already in the form of parallel DE 100 24 142 described a lattice structure of threads or wires, in the quasi Similar voids in the structure evenly distributed over the pack are preferred without, for example, the countercurrent gas phase  Flow channels are provided. The wire or thread structure fulfilled rather, evenly the packing space.

The object of the invention is a further development in which the principle of Trickle column comes into play more, namely as large as possible Exchange area between the phases with large free spaces To have flow cross sections and that the phases do not change penetrate each other, d. H. the energy-intensive back pressure as far as possible is avoided, but the liquid does not trickle freely, but follows predetermined paths in an even distribution.

This is due to the distribution of the one phase conducted in countercurrent as many current threads as possible, with the remaining free Flow space in the reactor is completely available to the other phase.

For optimal flow conditions are lengthways through the reaction chamber guided structures from linear liquid guiding elements in the form of Wires or threads provided the free flow channels for the limit counter-flowing medium.

The distance between the wires or threads arranged next to one another is so chosen that the liquid running or rising at these (e.g. at Extractions) cannot converge, but evenly around the wires or threads flow. That doesn't rule out wires or threads with theirs respective liquid flows are brought together in nodes in order the fluid then redistributed to the wires or leaving the node Let threads continue to flow in a corresponding manner.

For the constant renewal of the liquid surface they are next to each other arranged wires or threads are therefore preferably crossed with each other, d. H. merged into points or intertwined so that through the repeated  Start-up routes to improve the material and / or heat exchange Separator number / length unit (NTSM) increases.

Now, as is known, the required exchange area increases increased throughput accordingly. On the other hand, the fabric takes and Heat exchange rate also increases at higher speed, which increases the exchange area does not increase proportionally with the throughput, but rather only increases exponentially (with an exponent <1).

When the flow around wires or threads increases with increasing flow rate the film thickness and thus the Film surface. This is not the case with flat surfaces, since only with these the film thickness increases with film areas of the same size. Against is one Increased throughput for wires or threads with an increase in Phase interface and so with a reduction in the required specific volume.

After the inventive idea are mentioned by these two Flow processes and the throughput increases that are now possible intensifies conversions of production plants with large economical Benefit possible.

In its most general form, the task is performed by the characterizing features of claim 1 solved.

The elements conducting the liquid through the claimed device are called "linear liquid guide elements" or in short as "guide elements" designated. They consist of threads or wires or also each several bundled or bundled wires or threads (multifiles Braid) or corresponding linear components to which this one Component surrounding liquid flow can run off.  Some further definitions are introduced: the core of the claimed The device is the so-called "pack" in which the substance and / or Energy exchange takes place. Especially at the top, but possibly The linear liquid guiding elements are also at the lower end of the pack in groups and, if necessary, also gradually for distribution and Feed the liquid onto the pack or for the appropriate collection the liquid at the other end of the pack is bundled together. One from the actual pack and the described distribution or Collection structures for the liquid self-contained unit is called "Exchange unit" called. Such an exchange unit is preferred with their liquid feed bundles of the linear liquid guide elements for Task of the liquid collected in a drain spout over which the liquid the individual bundles usually with the same hydrostatic pressure is fed to the pre-distributor.

In contrast to previous proposals, the structure is according to the invention of the liquid guide elements in the package so that the Guide elements preferably lie in certain imaginary areas that, between there are relatively free flow channels for the counter-flowing medium limit. That does not rule out - and should not necessarily rule out essen - that the counter-flowing medium also through the guide elements containing surfaces partially into adjacent flow channels transferred and vice versa. It is essential that for the counterflow Medium preferred flow channels are provided that are less Loss of pressure lead, however, through the areas covered with guide elements are separated so that a good distribution of the counter-flowing medium in the basic thing is guaranteed. On the other hand, it is not a requirement that the preferred flow channels for the counter-flowing medium are completely free of liquid guiding elements. For structural reasons for the pack, but also for reasons of optimizing the substance and / or Energy exchanges can make sense, either an unhindered free one  To limit the flow of the counter-flowing medium or on the other hand, targeted liquid-carrying guide elements also partially into the Bring countercurrent channels.

In the imagined areas, a horizontal course of guide elements, if not some horizontal stabilizing elements for the Stability of the package is necessary, avoided if possible, d. i.e., the Liquid guide elements run at an angle to the horizontal, the can easily be larger than 45 °, since the general Flow direction through the packing finally in the vertical direction he follows. For constant liquid redistribution, the liquid Guiding elements preferably intersect in two opposite Oblique directions. This essentially results in a structure rhombic mesh with a vertical axis. The mutual distance the liquid guide elements or the size of the meshes formed is so Large to choose so that the liquid that is to flow along them does not close film-forming bridging between the guide elements or in the Mesh tends. Such film formation or one of guiding elements in one vertical surface supported film curtain is not in the sense of the present Invention. Rather, it is an essential feature of the invention that defined individual flows along the liquid guide elements through the Pack and also open areas for one certain passage of the counter-flowing medium into neighboring Flow channels remain.

A simplest arrangement of the pack according to the invention as part of the claimed device is that the guide elements in spaced, parallel vertical planes as obliquely and crosswise are arranged touching or intertwined, so that between them Levels in cross section long rectangular flow channels for the counter-flowing medium remain. In any case are with this  Embodiment the flow channels generally wider than their thickness is determined by the distance between the levels occupied by guide elements. The Guide elements on parallel planes can also be spaced apart be connected, especially if the stability of the package so requires.

However, embodiments are preferred in which the guide elements occupied imaginary areas, especially in cross-section enclose radially symmetrical, vertical flow channels. This Flow channels usually have a prismatic constellation, wherein the imaginary surfaces containing the liquid guide elements Shell surfaces of such a prism are.

A special embodiment of the invention is that the one Lateral surfaces surrounding the flow channel are curved in cross section, in particular have an elliptical or circular cross section. This can be useful for manufacturing reasons. The Liquid guide elements are then in the associated cylinder surface preferably arranged spirally in opposite directions, whereby Touch intersecting guiding elements in the crossing points. You can also in these intersection points are connected to one another like a node. In any case, a zigzag arrangement of the Guiding elements that ultimately lead to the same structure, the spiral However, the arrangement is simpler in terms of production technology.

Several such hoses arranged on cylindrical surfaces Guide elements can now be used vertically to form a pack be arranged side by side, preferably mutually touch. The areas of contact can be considered light mutual Flattened surfaces can be formed. They are in the contact areas Guiding elements of adjacent hoses in connection with each other, creating a certain liquid redistribution takes place between the individual units  can. A certain disadvantage of the cylindrical design is that gussets arise between the adjacent cylinders, which then form a Form the type of flow channels of smaller cross-section.

To avoid this, the prisms have guiding elements have a polygonal cross-section. You can neighboring prisms have common partial lateral surfaces. In case of Prisms with a triangular, rectangular or hexagonal cross section can thus be used a dense, gusset-free cross-sectional structure of adjacent Generate flow channels through the with the liquid guide occupied, imaginary outer surfaces are separated.

This results in a regular polygonal grid in cross section, whose grid lines are the cross-sectional lines of the imaginary vertical surfaces are. The linear liquid guide elements are preferably arranged such that they intersect at the intersection of the grid lines of such a structure form, with nodes again at a fixed vertical distance are present, which then have an identical adjacent cross-sectional plane form the same grid. Two neighboring nodes of a raster plane form with the corresponding two nodes of the next raster level a rectangle. The liquid guiding elements are now preferably of this type arranged that a guide element from two neighboring nodes at an angle to the other node of the neighboring raster plane runs, so that these two guide elements in the above Cross the rectangular area. The imaginary lateral surfaces of the prismatic The structure of the pack is thus such that intersecting guide elements characterized.

As already mentioned above, guide elements from one node to a non-adjacent node in the next Be raster level, which then obliquely through the flow channel  run. This can be used to control flow resistance and also for redistribution of the liquid may be desirable.

The prerequisite for optimal functioning of the device is initially called uniform liquid supply, for which the by the Reaction chamber guided guide elements in a preferred embodiment, multi-stage combined into bundles and at the liquid feed points in Drain spouts are supported.

At the bundles of guide elements arranged around holding mandrels their implementation formed by perforated disks uniform slots. A preferred embodiment is that these uniform slots through included round bundles of guide elements on the one hand and different ones Perforated radii of the perforated disks, on the other hand, arise and thereby create a system at the vertices so that crescent-shaped column around the sleeves of the Guide element bundles are formed.

The drain spouts held side by side are replaced by common Pre-distributor fed. Here, the concentrated arrangement of Drain nozzles of the pre-distributor equal amounts of drain to the drain nozzles can be achieved, with installation deviations of the drain nozzles not important play.

Another advantage is the feeding of the large number of drain spouts through a common pre-distributor that only this with mobile installation gimbal needs to be hung and even in this case same-sized liquid drain due to the same level of liquid in the Pre-distributor takes place.

To avoid running on the inner wall of the reaction space Liquid is in line with the arrangement of the longitudinal  Guide elements expediently a diagonal braid on the inner wall of the Device or, in the case of small dimensions, directly around the reaction pack arranged.

The device is explained according to the following drawings. in this connection shows:

Figure 1 is a schematic side view of a liquid feed device with a pre-distributor and outlet spouts held side by side.

FIG. 2 shows a schematic top view of the drain spouts of FIG. 1 held side by side;

Fig. 3a shows a schematic plan view of the stepwise liquid distribution in a square grid cross section of a reaction package;

FIG. 3b as shown in FIG 3a with juxtaposed circular flow channels.

FIG. 3c as shown in Figure 3b with closely juxtaposed circular flow channels.

Fig. 4 is a schematic cross section through a perforated disc of the discharge spout with liquid disposed therein vanes;

FIG. 5a is a schematic side view of running a quasi-triangular vertical flow channel fluid guide elements;

FIG. 5b is a schematic side view of the extending around a quasi-rectangular vertical flow channel fluid guide elements;

Fig. 5c is a schematic side view of the extending around a quasi-hexagonal vertical flow channel fluid guide elements;

. Fig. 6 is a schematic side view of two of Figure 5a juxtaposed quasi triangular vertical flow channels with up and down stepwise combined liquid guide elements;

Fig. 7 as Fig. 6, but with three quasi-round vertical flow channels arranged next to each other with liquid guiding elements that are gradually combined at the top and bottom.

The arrangement for distributing the liquid fed to a trickle or reaction column is explained with the aid of FIGS . 1 and 2: FIG. 1 shows, in a schematic side view, a liquid feed device 1 with a pre-distributor 2 and discharge nozzles 3 arranged therein next to one another on the same level.

By separating the liquid feed between the pre-distributor 2 and the outlet spouts 4 , the discharge quantities are independent of installation deviations of the outlet spouts 4 and these can be mounted on holders 5 separately from the liquid feed device 1 .

The same amounts of liquid flowing through the nozzles 3 through pipes or hoses 6 determine solely the amount of liquid flowing out of the outlet spouts 4 via bundles of liquid guiding elements 7, regardless of any installation accuracy.

FIG. 2 shows the outlet spouts 4 arranged on the holders 5 , which are distributed over feed points 8 of the exchange elements 9 .

To prevent the liquid from going to the edges, a braid 10 or other deflectors are arranged on the inner wall of the reaction space or around the exchange elements 9 .

Fig. 3a shows a schematic plan view of the principal stepwise liquid distribution of distribution points 11 of the discharge spout 4 according to one below the other distribution points 12, 13 arranged side by side square exchange elements 14.

FIG. 3b shows comparatively to Fig. 3a shows the principle of stepwise liquid distribution of distribution points 11 of the discharge spout 4 according to one below the other distribution points 12, 13 on round juxtaposed exchange elements 14.

Fig. 3c shows comparatively to Fig. 3b, the principle of stepwise liquid distribution instead of four in the three directions of distribution points 11 of the discharge spout 4 to be superposed distribution points 12, 13 in closely juxtaposed round exchange elements 14.

Fig. 4 shows the bundle of liquid guide elements 7 guided through a perforated disk 15 , wherein uniform slots 16 are formed by different radii of a perforated disk 15 and the bundle of liquid guide elements 7 and thus the latter abut the openings of the perforated disk with their vertices 17 ,

FIG. 5a schematically shows the example of a 18 arranged at the corners of a triangular grid longitudinally extending liquid guide elements 19 which intersect between adjacent cross-sectional planes 20.

A vertical triangular flow channel 22 is formed, as it were, by these guide elements 19 , which run longitudinally and intersect on the lateral surfaces 21 .

Fig. 5b shows corresponding to Fig. 5a is a formed by the intersecting vanes 19 almost square vertical flow channel 23.

Fig. 5c schematically shows the arrangement of the six lateral surfaces 24 of a hexagonal prism intersecting vanes 19 that form a quasi-hexagonal vertical flow channel 25.

Fig. 6 is a schematic side view of two juxtaposed quasi triangular flow passages 22, in which the intersecting vanes are drawn thick 19 on the front lateral surface 21 of the right triangular flow channel 22.

A three-dimensional packing is formed by repeated parallel arrangement of the flow channels 22 . The guide elements 19 running longitudinally at the intersections of a triangular grid are combined stepwise at the top and bottom into bundles 26 and 27 of guide elements, the upper guide element bundle 26 being held in the outlet nozzle described.

FIG. 7 shows, similar to FIG. 6, quasi-circular flow channels 28 arranged next to one another with the guide elements 19 crossing on the circumference of the flow channels 28 , which are also combined up and down in stages to form bundles 29 and 30 , the upper bundle 29 in the outlet nozzle described is supported.

Claims (24)

1. Device for the general vertical flow of a liquid in a trickle column, with linear liquid guide elements in the form of wires or threads or bundles of wires or threads, characterized in that the liquid guide elements are primarily in a substantially vertically oriented, horizontal cross-section rectilinear or non-rectilinear, for example curved, imaginary surfaces which delimit flow channels between them for the counter-flowing medium. 2. Device according to claim 1, characterized in that the Liquid guiding elements in all sections of their course within their surface course an inclination to the horizontal exhibit. 3. Apparatus according to claim 2, characterized in that the Liquid guiding elements form a mesh structure in their surfaces, by in particular inclined liquid guiding elements cross or generally vertical bundles of liquid Guide elements between nodes in individual guide elements on the side are spread out and with corresponding individual guide elements adjacent bundle in contact. 4. The device according to at least one of claims 1-3, characterized characterized in that the liquid guide elements such Have a distance from each other or the meshes of such a size have that the distance between adjacent guide elements film formation spanning or filling the mesh flowing liquid is avoided.   5. The device according to at least one of claims 1-4, characterized characterized in that the liquid guide elements in parallel vertical surfaces and long rectangular cross sections Flow channels for the counter-flowing medium between them limit. 6. The device according to claim 5, characterized in that the Guide elements of the individual parallel surfaces at intervals Cross elements are interconnected. 7. The device according to at least one of claims 1-4, characterized characterized in that the containing the liquid guide elements Surfaces are surface areas of a vertical prism, the Interior a flow channel for the counter-flowing medium forms. 8. The device according to claim 7, characterized in that the vertical prism has a curvilinear cross-section, in particular the lateral surfaces are those of an elliptical or Circular cylinders and the liquid guide elements are spiral in this Shell surface are arranged. 9. The device according to claim 8, characterized in that the Liquid guiding elements are arranged in opposite directions, crossing one another. 10. The device according to claim 8 or 9, characterized in that the lateral surfaces of adjacent cylinders are linear or light are in flat contact with each other under mutual Contact of the liquid guiding elements in these contact areas.   11. The device according to claim 7, characterized in that the The lateral surface of the prism is that of a prism with a polygonal one Are cross-section, especially with triangular, rectangular or are hexagonal cross section. 12. The apparatus according to claim 11, characterized in that neighboring prisms form common partial lateral surfaces. 13. The apparatus according to claim 12, characterized in that the Arrangement of a large number of adjacent prism surfaces three-dimensionally structured packing forms, with parallel ones, through the prismatic areas limited same flow channel for that counter-flowing medium. 14. The apparatus according to claim 13, characterized in that the Packing in a cross-sectional plane a regular polygonal Grid forms, whose grid lines are the cross-sectional lines of the Surfaces containing liquid guide elements, or crossing points of the liquid guide elements in the Intersections of the grid lines lie and guide elements of these Nodes starting in the areas to the neighboring ones Nodes in the intersections of a next higher or next lower cross-sectional level. 15. The apparatus according to claim 14, characterized in that in each case from two neighboring nodes in a cross-sectional plane the other node in a neighboring one Liquid guiding elements running in the cross-sectional plane are located in the cross the area containing these nodes.   16. The apparatus according to claim 14 or 15, characterized in that in addition to flowing into a flow channel for the counterflow Medium-guiding surfaces of liquid guiding elements Liquid guiding elements are provided by a node a cross-sectional plane through the flow channel diagonally to one Node of an adjacent cross-sectional plane. 17. The device according to at least one of claims 1-16, characterized characterized in that liquid guide elements on the upper and / or lower ends of the device are grouped for the distribution of liquid to be given up or collection of running liquid. 18. The apparatus according to claim 17, characterized in that the Liquid guiding elements grouped together in several stages are. 19. The apparatus according to claim 17 or 18, characterized in that the liquid guiding elements combined for the liquid feed are held in drain or inlet spouts. 20. The apparatus according to claim 19, characterized in that the summarized liquid guide elements arranged around holding mandrels and are guided through perforated disks. 21. Device according to claims 19 and 20, characterized in that that these uniform slots are enclosed by round guide elements Bundle on the one hand and different hole radii of the perforated disc are formed on the other hand, with the sleeves of the guide elements Bundle at the vertices of the holes.   22. The device according to any one of claims 19-21, characterized characterized in that several of the side by side Drain spouts are connected to a common pre-distributor. 23. The device according to claim 22, characterized in that the Pre-distributors are gimbaled. 24. The device according to at least one of the preceding claims, characterized in that a diagonal braid on the Inner wall of the device or arranged around the reaction pack is.