DE1960721U - EXCHANGE COLUMN FOR TWO FLOWS. - Google Patents

Description

T 1? 839 / 12a Gbm March 17, 1967

TISSMET & L LIONEL-DÜPÖNT, TESTE et Cie. Lyon, France:

Exchange column for two fluids

The innovation concerns exchange columns for two streams, medium with filling material arranged in a pipe jacket

body elements.

If a mass transfer between two phases is carried out in a column provided with random packing, which is as favorable as possible Conditions to be effected, one will first strive to reduce the contact area between these two To enlarge phases, but at the same time the level surfaces of the concentrations flat and perpendicular to the To keep the axis of the column.

Efforts will also be made to achieve a large concentration gradient with low pressure losses.

In a still, the level surfaces of the V _ Concentrations be horizontal surfaces in which:

Wels: This document (description and work claim) is the last one submitted; sf3 differs from the cter wording of the originally eihgor & ieliteri LHsriogsr. ob. Dfe racfcHioho B ^ iiiurig of A waiahi:;. · ;. irf .-, jj-, ι pvor.ifr. irsptöngiiuh singerercbten Uf * si-togi.n bef ^ Bn in dtn Arnteck-bi :. Sia kc., _T. I-jvJv'-r.-.-- "* i ■ rΛ'.ϊ ^ s rschtlicrien interest gsbührenfejf viewed warden ^^^.. Upon request, hiscvon om fcr- :. ,,, _fl ooi-r ri; mfve delivered to ObRchen prices. German Patent Office, Gebrauehsniusiersfelle, ~ 2 ~

the liquid phase and the vapor phase are in equilibrium * »To ensure a good efficiency of the column to ensure two successive equilibrium sf laugh (causing a separation of the mixture by an imaginary one; Corresponds to the intermediate floor) are as close together as possible. .

In practice you can often find that in a packing preferred flow paths for the two. Form phases * This takes up a large part of the fill « body volume does not participate in the exchange process because ent * xtfeder there is too much steam in this part or, on the contrary, it is flooded with too much liquid. In both cases, respectively both phases are not present and the packing height in which this type of flow develops is not fully exploited. Such a phenomenon is generally mean irreversible and, when it occurs at a given point, settles to the bottom of the column away.

Experience shows that for the proper operation of a packed column, the following mentioned conditions must be given. First of all, what the requirements for the packing are If the filler has a large surface per unit of space of the filler body and this surface must be Packing volume should be evenly distributed (homogeneity).

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In addition, the packing must be constructed so that he can distribute a local excess of one or the other phase and spread over a larger area (local self-distribution). The packing may only cause low pressure losses and must for one wide range of specific throughput rates can be used be. It must have a handy, easy-to-use form and be resistant to those in operation occurring mechanical stresses. Finally, the packing must easily get into the column can be used and in operation resistant to be chemical agents *

As for the conditions of use of the packing, so it will only achieve its maximum efficiency if the following principles are observed. in the upper part of the column and below the feed line * » An even distribution of the liquid phase must be guaranteed below the filling level for an even distribution of speed in the Flow of the vapor phase can be taken care of. It must be possible to observe the even distribution of the two phases restore every point at which there is a risk of one Flow due to external influences, such as cross-section changes changes, leads, measuring instruments, etc. exists. After all, every danger of an education must be preferred Flow paths can be excluded by the fact that after the passage "through a certain filling body height

one suitable, equally effective for both phases, Provides redistribution.

The aim of the innovation is to benen disadvantages of the known packing to eliminate by observing the above-mentioned conditions.

Another goal of the innovation is the emergence to prevent two phenomena, which in large part contribute to the efficiency of the known To worsen the packing, as has been determined by experiments, as these phenomena add to it contribute to creating preferred flow paths for the two phases in the packing.

These are the following phenomena:

a) Presence of radial velocity components in the current. \: -

b) Progressive confluence of the liquid (along their flow path) in relatively small buckets Area of the column cross section after flowing through a certain packing thickness.

According to the innovation, this is achieved by the fact that the actual packing of each element, i.e. the solids e complex structure, over which the fluid flow through at least one partition wall into thin, vertical

right layers is divided, this dividing wall the radial component of the flow velocity cancels and thereby the flow means a vertical one Forcing way.

In such a configuration it is extremely two-fold moderate that the packing elements are combined with intermediate bottom, in which each for one of the two Fluid certain passages distributed as evenly as possible over the entire area of the false floor are. Because of such a configuration, it is possible to use very large diameter and exchange columns to build great height without the risk of the gas or liquid distribution within the Exchange column is uneven.

The FüUlkörperelemente according to the innovation can with Intermediate floor can be combined in which passages, each intended for one of the two fluids are distributed as evenly as possible over the entire surface of the floor. These floors can not only be used in arranged upper part of the column, but also between two stacked groups of packing elements be used, with the bottom each carrying the upper packing group.

According to a particularly advantageous embodiment of the Innovation can_the_the_fill element forming solid «* -

body complex structure through multi-thread, gaufrier " tes tricot fabric be formed,

Further features of the innovation emerge from the following description, in which several embodiments with reference to the accompanying drawings. It. demonstrate:

1 is a schematic sectional view of a distillation column with packing elements, as well as with a top base and arranged between the elements Intermediate floors, according to the innovation

Fig. 2 is an enlarged sectional view of the column along the line II-II of Fig.l, in which a first embodiment of a packing element is shown j

3 shows a schematic, perspective illustration of the packing element of FIG. 2 when rolling up ^

FIG. K shows a sectional view corresponding to FIG. 2 of a second embodiment of the filler element j

Fig. 5 is a schematic, perspective illustration of the construction of the element shown in Fig. 1 ± with parts thereof broken away;

Pig.6 a cross section through the column at an enlarged scale taken along the line VI-VI of Figure 1, this shows a ⁷ Sehnitt Zwisohenboden for the uniform distribution of the fluid!

7 shows a section along the line VII * .VII of FIG. 6'j

8 shows a partial sectional view corresponding to FIG. 7, '' which represents the part of a head distributor tray, the opposite: an intermediate floor designed differently; is and ν- '""

9 is a perspective view of a formed as a liquid collector Füllkörperelementes _r wherein a limited by two perpendicular planes part is broken out of the element.

Fig. 1 shows a very highly schematic representation a distillation column to be regarded as a particularly advantageous form of application of the subject of the innovation is.

In the illustrated embodiment, this column has several, mutually arranged in alignment with each other and verflansch-th cladding tubes 1, wherein at the uppermost ^r tubular casing, a head cap 2 and at the lowest casing pipe a floor pan is flanged. 3

In these casing pipes, packing elements k are each layered one on top of the other in groups of several elements, these groups being separated from one another by increasing prices. The distributor bases marked with the reference number 5 (FIGS. 6 and 7) are simply inserted between two groups of elements, while the distributor bases marked with the reference number 6 (FIG. 8) are fixed between the connecting flanges of two successive casing parts. Between the flanges of the uppermost jacket tube and the head cap 2 there is also a distributor base 7, which corresponds to the distributor bases 6; finally, below the last distributor base 6 in the base pan 3, there is another packing element 8 which, depending on the intended use there, serves as a liquid collector is trained.

In the following, the packing elements k and 8, as well as the intermediate floors 5, 6 and 7, which together form the actual subject of the innovation, are to be described in more detail. However, the functions are also described which the distillation column shown in FIG. 1 has to fulfill, without going into detail on the means well known to the person skilled in the art, which are necessary for fulfilling these functions and their effect with those of the packing elements 4 and 8 and the intermediate floor 5 and 7 combine, the effect of the packing elements and the intermediate floors clearly emerging from the following description.

Functions of the column come into question:

a) absorption,

b) washing, "'." "' - ■ -." ■■ /

. .-- ©) extraction of a liquid from a _liquid,::; "..." -. "■;.: -.""■. D) dividing; two liquid phases, '&) gas humidification,:
^; -f) -> drying a steam,

g) ^ ncontact bring sound two vapor phases,

h) / heating a gas (with the packing in "" ";" ■■ a; Heizmamtel is arranged),

i) Bringing different phases into contact with each other »

waiting of _catalysts;

f) Removal of the liquid from a liquid with ι Particle-enriched steam.

In the case of the packing elements k , according to the innovation _j, the complex structure forming each individual element is subdivided into thin, vertical layers or slices by at least one partition wall. The solids are preferably made of multi-threaded, embossed tricot fabric.

According to a first, shown in Figs. 2 and 3, The partition wall consists of "- a continuous, more or less rigid one "and impermeable tape 9_. This separator tape and

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At least one: tricot fabric tape (in the example shown two tricot ribbons 10) are rolled up together. In this case, the dividing wall has the shape of a spiral with a constant pitch, the turns of which form one spiral corridor delimiting that of the jersey ribbon is filled and flowed through by the two phases «

According to a modification of this first embodiment not shown in the drawings, there is the partition from a large number of concentrically nested sleeves, between the coats of embossed tricot fabric are inserted.

In a second, shown in Figs Embodiment, the partition consists of several semi-rigid, impermeable or semi-permeable foils 11, which are arranged between layers 12 of embossed tricot fabric. Each fabric layer can be one or more Strips include - (two strips in the illustrated embodiment), the embossing of which can be opposite to one another,

In order to achieve good effectiveness, the division brought about by the partitions must be such that the Distance between two successive partitions (i.e. between two adjacent turns of the tape 9 or between two "adjacent concentric sleeves or-between two adjacent foils 11) in relation to

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the diameter of the column is small. If this is the case, the partition arrangement lifts the badial component instantaneous flow rate of the phases at a given point and represents the two-dimensional Flow again.

This vertical partition wall thus channels the flows of steam and liquid, thereby facilitating their meeting. A column provided with this dividing wall of the type customary in der.Industrie can thus be regarded practically as a parallel arrangement of a large number of columns of small diameter.

The partition arrangement according to the innovation also enables "the creation of an absolutely uniform filling body, because for this purpose only the distance between the successive layers needs to be precisely maintained when producing the elements k arranged sleeves of the same thickness or group of flat /, parallel, equally spaced layers), they each enclose elements of the same volume, which contain equal amounts of substance of the zones in which the exchange processes take place. - ::,]

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Is from the foregoing, ersiehtlieh is that each packing element k viewed microscopically completely homogeneous _r * This is necessary to avoid local disturbances of the Strömungsgleiehgewiehtes which wfrden very quickly result in two phases in the formation of preferential flow paths with constantly increasing Durchflüßmenge.

In addition, have carried out with the innovation

$ Experiments demonstrated that the differences of the liquid flow rate was reduced from one point to another of the same cross-section to 1/5 of what they would be if the / packing elements would not have been provided with vertical partitions. With the arrangement according to the invention one thus achieves a considerable

* Reduction of the corresponding to a theoretical intermediate floor ^ increasing height without the need for higher pressure losses

needs to take into account. .- ".- ■■"

The edges of the partition wall or the partition walls can be smooth or toothed, serrated or the like. In the latter;

; Fall of the interlocking of two stacked one on top of the other

Elements is favored.

The partition or: the partition walls can be made of impermeable - .. porous / or semi-permeable "material". will. In the latter case you can _: "pressed, shaped

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Fabric or perforated; , cut out sheet metal or Like, be made, such partitions the Exchange by diffusion from one - layer of the embossed tricot fabric to another and favor at the same time regulate the extent of this diffusion.

The surface of the partition or walls can be smooth (e.g. rolled steel strip), rough (sandblasted or chemically roughened steel band), or shaped (embossed, cellular embossed or punched steel band, etc.).

The partition or walls can have a certain rigidity exhibit. They can be semi-rigid (e.g. cold-hammered, non-annealed steel strip) or very pliable (e.g. thin, annealed steel strip). Optionally, the partitions can also be supple and elastic, in particular so that they fit closely to the irregularities of the Can adapt packing fabric.

The partitions can be made of metal, plastic or other synthetic materials. They can also be subjected to a suitable surface treatment in order to to make them suitable for the respective fluids to be brought into contact and their reaction conditions, this surface treatment being a heat treatment, chemical or mechanical treatment.

Finally, the partition walls can be covered with a more noble material, this material by any suitable funds can be applied. The coating can be applied, for example, by electroplating (Tinning, chrome plating), by vapor deposition of metal in a vacuum, by spraying on metal, by spraying on of aluminum oxide or other ceramic materials with the plasma torch, by pyrolysis (application of carbon) and the like. The partitions can also be covered with a layer of a material that suits them for any chemical reactions / that take place in the packing should give the property of a catalyst

(chemical reactor). In the latter case, for example, kalman Apply aluminum oxide, finely divided nickel, platinum black and the like.

The features and properties of the vertical partition walls described above also apply to the lower, Packing element 8 (FIG. 9) designed as a liquid collector. With this special version, the Embossed tricot fabric of simpler construction forming layers 13 Be of weave or of simpler construction. The aforementioned layers are separated by a spiral. wall 1 ^ 4- separated from each other, which of the above Partition 9 corresponds. The lower band of the partition wall l * l · is designed as a single 15, which is 4m in cross-section widened and sloping from the center outwards

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runs. In other words, as can be clearly seen from FIG. 9, the lower edge 16 of the filler layers of the element 8 is higher than the lower edge of the spiral partition 14 and the channel 15, which forms the lower edge of the partition, runs in the form of a spiral on a imaginary conical surface 1 sloping towards the outer edge? » This trough 15, which has the shape of a conical spiral, has a continuous gradient on the imaginary conical surface 17 due to its spiral shape and a cross-section that widens along this gradient, so that the liquid can be drained off under the most favorable conditions. The channel 15 opens out above an annular collecting space 18 which is formed in the base pan 3 and which is connected to a drain pipe 19 so that all of the liquid can be recovered and drained off. "■ .:

The packing element 8 described above can be on lower end of a column ^ of the kind shown in Fig. 1 can be used as a liquid collector * Its use is also possible as a liquid collector under a boiler, as a precipitation stage at the lower end of a rectification column, etc ..;

It goes see that when the packing elements Ψ the edges of the partitions are ausgebilM different "* - You are in hoi ^ öntalenvEbeneiieia _(^ and the height of the partition · -: - or" walls is; less ^ s that ^ the ^ R & I! ! body tissue layers, - with it

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the latter protrude slightly in order to improve their connection with the corresponding skin layers of the adjoining sensor body elements k .

According to the hiring, the vertical partitions of the packing elements are V rait a horizontal partition arrangement combined, which is formed by distributor trays 5 and 6. It is in spite of the impeccable macroscopic homogeneity of the packing elements not possible, the even distribution of the two flowing phases for one to be maintained indefinitely, i.e. over a very great height; it is also not possible to maintain phase equilibrium Always keep the surfaces flat and perpendicular to the axis of the column.

In order to restore the flatness of these equilibrium surfaces, distributor trays 5 and 6 are provided, which the Subdivide packing elements 4 into several groups, the level of which is the minimum quality of the desired phase distribution is equivalent to. As can be seen from the description below, these bases allow mixing and homogenization of the two phases, because they distribute them equally in the cross-section above and below them. Such distribution trays can not only be used in a column provided with the packing elements, but also in columns which are filled with other packing elements.

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As shown in Figures 6 and 7, each of the intermediate trays 5 and 7 comprises a plate 20 which extends transversely to the axis of the column and over the entire cross-section thereof. The plate 20 is firmly connected to an annular wall 21 arranged on its upper side and, together with this, forms a. Trough 22 in which the liquid collects up to a certain height, which depends on the operating mode of the column. The annular wall 21 is only provided for the intermediate floor 5, while it is replaced in the intermediate floor 6 and at the top floor 7 by the upper jacket tube ln (see FIG. 8). The liquid collected in the tub 22 is homogenized in its entire mass and, distributed through a multiplicity of holes 23 in the plate 20, is fed to the filler element located below the intermediate floor. The number, shape, diameter and distribution of the holes are to be determined through tests for the respective operating conditions of the column. The holes 23 must be designed so that at the lowest throughput liquid flows through all the holes and at the highest throughput the liquid level in the tub 22 stabilizes at the level of the upper edge of the nozzle 2k , which are tightly connected to the "plate 20 and flows through the steam In this way, a considerable reserve of liquid is created, which avoids the disadvantages which could result from a not completely horizontal position of the intermediate floor

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Avoided point of the same cross-section, which the most serious disadvantage of a not completely horizontal Form location. ■ ".". ;;; ■ ^; /

The one for the even distribution of the liquid phase provided holes 23 each point on their exit side a ^ orspringenae lip on, so that the out of the holes exiting; fine jets of liquid are well guided and cannot flow along the underside of the diaphragm. The nozzles formed in this way generate thin jets of liquid, which are stable and precisely controllable.

The nozzles 24 have a large passage cross-section for the steam and are evenly distributed on the plate 20, so that the intermediate floors result in a pressure loss which is negligible compared to the normal pressure losses occurring during passage through the packing covered by caps 25, which are designed to drain the liquid emerging from the overlying filler element 4.n into the trough 22 and to prevent the liquid from flowing directly to the filler element 4.n + 1. In this way, the total liquid emerging from the element 4.η with the liquid in the tub 22. The caps 25 are held by two brackets 26 and 27 at a distance from the upper opening of the nozzle 24, these brackets being so stiff that the caps 25 the upper packing elements

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mente ty.η, ty.η - 1, ty.η - 2, etc. The caps 25 of an intermediate floor thus form a very large one Support provided in-between for each overlying one Packing element.

In the case of the intermediate floor 6 and the upper floor 7, the plate 20 is in each case between the flanges 28.η and 29.η + 1 of the adjacent casing pipes l.n and l.n + 1 (intermediate floor 6) or the upper jacket tube 1.1 and the head cap 2 arranged (bottom 7). Between the plate and the flanges are Seals 30 are arranged and the arrangement thus formed is by collar rings 3I, 32 and by not shown in the drawing Screws (see Fig. 8) or any other suitable means held together.

In the case of the intermediate floor 5, an annular seal 33 made of elastic material is placed around the hanging wall 21, which against the plate 20 rests. A sleeve 3ty is arranged over this seal, which under the action of clamping means stands and compresses the seal so that it is firmly and sealingly on the corresponding jacket tube 1 and on the plate 20 is present. As shown in the drawing, these clamping means can consist of screws 35 which secure the plate 20 and enforce the two legs of U-shaped bracket 36, the ends of the legs against the upper edge of the Sleeve 3ty_b or Support against the screws via a nut 37. The screws 35 also allow the attachment of; Spacer feet 38 under each plate -20, see "these" feet support against the lower packing element-ty.η + 1. '

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Regardless of the embodiment de ^ floors 5 and 7, they enable the following functions through their effect as horizontal partition walls in conjunction with the vertical partition wall arrangement; : ^; _r ; _; , - ■ -..- "

a) The distribution of the downward flowing liquid phase in the lower packing element is uniform.

b) The distribution of the ascending vapor phase in the upper Packing element is uniform.

c) The liquid phase is homogenized in the tray of the false floor.

d) The homogenization of the vapor phase takes place in the located below the plate Feien space, which space allows the generation of convection of the gaseous phase and the formation of a pressure balance, which in _addition:; favorable effect on the mass transfer between the phases and the distribution thereof can affect.

e) By pulling off the shelf retained in the basin Liquid it is possible to take liquid at certain heights of the column.

In addition, the horizontal subdivision forms a support for the groups of packing elements, which prevents that these are squeezed together.

The innovation is not limited to the illustrated and described embodiments; underwent numerous changes to its framework.

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In addition, the use of such a packing arrangement according to the innovation not limited to distillation columns, but can be extended to all columns, in which there is a mass exchange between two phases as well as all chemical reactors in which two or more different phases are introduced in order to make them react with one another.

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Claims (17)

S eh u Vt ζ a ns ρ r ü e h e 1. Exchange column for two fluids with arranged in a drilling jacket packing elements, characterized in that the actual packing (10,12) of each element (M-, 8), ie the solids complex structure over which the fluids flow through at least one Partition wall (9,11) is divided into thin, vertical layers, this partition wall (9,11) canceling out the radial component of the flow velocities and thereby imposing a vertical path on the flow means. 2. Exchange column according to claim 1, characterized in that the dividing wall (9, 11) of the packing elements (^, 8) is subjected to a suitable surface treatment according to the type of fluid to be brought into contact with one another and their reaction conditions. ^t \ ; 3. Exchange column according to claim 1, characterized in that the dividing wall (9, 11) of the packing elements (^, 8) is pliable so that it closely follows the irregularities of the packing (lO, l2) adapts. 4. Exchange column according to claim 1, characterized in that the dividing wall "(9, 11) of the packing elements (4.8) is permeable in order to enable a controlled exchange through diffusion from one layer to the other » 5 »exchange column according to claim 1, characterized in that that the partition (9,11) of the packing elements (4,8) as Catalytic converter is designed for the reaction of the fluid » 6 »Exchange column according to claim 1, characterized in that that the partition (9,11) of the packing elements (4,8) as Carrier for a catalyst is used » 7 »Exchange column according to claim 1 _? characterized in that the vertical layers (9,10 ^ 11,12) of the packing elements (4,8) are arranged in a spiral » 8, exchange column according to claim 1, characterized in that that the vertical layers (9, IQ, 11,12) of the packing elements (4,8) are arranged in the form of cylindrical rings: 9 # exchange column according to claim 1, characterized in that that the vertical layers (9,10,11,12) of the packing elements (4,8) in the form of parallel, flat and planar passages are arranged »T 10. Exchange column according to claim. 1, characterized in that that the partition (9, 11) of each packing element (4) is an unevenly cut band has to the interlocking of two stacked To facilitate packing elements (4). 11. Exchange column according to claim 1, characterized in that the dividing wall (9, 11) of a packing element tes (4) is shorter / than the packing (10, 12) to connect the packing £ 10, 12) of two stacked To favor falling body elements (4 ·). 12. Replacement column / iach claim 1, characterized in that « indicates that the partition wall (9, 11) at least one fill " body element (8) in its lower part longer than the Filling body (10,12) and in the form of a conical One (15) to catch and divert the » is formed downwardly flowing fluid. 13. Exchange column according to claims 1 to 12, characterized ^^ gekennzeichne11 that the packing elements (4.8) with Intermediate floors (5 * 6.7) are combined in which the because the passage determined for one of the two fluids is as uniform as possible over the entire surface of the intermediate tern bottom (5, ^, 7) are distributed. 14 _.: Ausaüschkolänne according to: claims 1 »13, characterized in that1-die; Intermediate base (5j6,8) uer not only in the upper part K © _lonne: (l) -but between two ti * Groups of Püllkorperelemente layered on top of one another
(4, 8) are arranged, whereby they mechanically support the upper group of the filling body elements (4). ; 15. Äustausehkolonneiiaoh claims 1 to 14, since « marked by that the intermediate shelf (5 * 6,7,20) through a clamping system (28,29,30) directly sealing on the inside «- wall of the column (1) are attached. ^ 16. Exchange column according to claims 1 to 15 »« characterized in that the intermediate tray (5,6,7,20)
Nozzles (24) with a large cross-section for the passage of the ascending fluid, whereby caps (25) are arranged on these nozzles (24) at a distance from their opening, which caps (25) belong to a group of filling elements.
elements (4) serve as a support and the downward flowing I «Divert fluid. 17. Exchange column according to claims 1 to l6, characterized in that the intermediate tray (5,6,7,20) with Holes (23) for the passage of the downward flowing stream are provided with a downward jump » have low lip, which is used by the ■ Holes facing under outflowing fluids in vertical ; To guide rays.