DE1152432B - Plate condenser evaporator, especially for gas and air separators - Google Patents

Description

J Plate condenser evaporators, especially for gas and The invention relates to a plate condenser-evaporator, in particular for gas and air separators, with corrugated sheet metal fittings in each of the media rooms, which on both sides abut against flat plates that tightly separate the heat-exchanging media and form a solid block with them, and with devices for Passage of the condensing medium essentially from top to bottom and the medium to be evaporated from bottom to top.

There are already various designs of such plate condenser evaporators known. In a11 of these bodies, the height of the block is vertical Separating plates with corrugated iron wiper layers larger than its horizontal extension. In particular in the case of larger structural units, there is the disadvantage that on the evaporator side a relatively large static liquid height from the resulting vapor bubbles must be overcome. This causes vapor bubbles to form in the lower layers delayed, so that only the sensible heat of the liquid increases. This will that which is available for the heat exchange with the medium to be condensed In many cases, the temperature gradient is sensitively reduced and, as a result, the performance of the apparatus strongly throttled.

In addition, the flow rate of the to be evaporated Medium in the known types at least in the lower area, in which none Vapor bubbles occur, low.

These difficulties are accompanied by a corresponding increase in performance of the plate condenser evaporator according to the invention overcome in that the block of vertical panels with corrugated sheet metal fittings for a given width Total length in the direction of the plate planes, which is at least the height of the block reached, but preferably exceeded by more than 501 / o.

It is essential for a further feature that the height of the block is at most 1 m, preferably 400 to 600 mm.

Furthermore, according to the invention, an arrangement is particularly advantageous hit, after which at the top open edge of the separating plate spaces for the to evaporating medium along at least one outer longitudinal wall overflow slots an overflow manifold are provided, which in the inlet line for the medium to be evaporated returns, while for the withdrawal of the evaporated medium from the collecting space located above the heat exchange block at least one Outlet nozzle is provided. In this way it is achieved that the entire evaporator heating surface Not only is it flooded, but also the medium to be evaporated with a high flow velocity is circulated flowing upwards between the heating plates. The concentration of Vapor bubbles in the evaporator cross-section can be optimized with respect to set the specific heating surface output and an incrustation-free operation.

The corrugated iron fittings are arranged so that the generators the corrugated iron fixtures between the panels in the area of the side entry openings obliquely upwards for that to be evaporated or downwards for that to be condensed Medium are arranged while moving upwards for that to be evaporated or after below for the medium to be condensed, corrugated sheet metal fittings with vertical generators connect.

In another preferred embodiment, the plate condenser evaporator constructed so that for the supply of the medium to be condensed openings at the top Part of at least one side wall and for the supply of the medium to be evaporated or a bottom collector is provided for the removal of condensate and possibly residual gas are, in the interstices for the medium to be condensed in the area of lateral inlet connection as well as below above the bottom collector for the to be evaporated Medium the generatrices of the corrugated iron fixtures obliquely downwards and in the middle Area are arranged vertically, while the generators of the corrugated sheet metal fixtures in the spaces for the medium to be evaporated down above the bottom collectors for that. to be condensed Medium obliquely upwards and in the upper Part run vertically.

With particular advantage, especially for installation in double-column rectifiers of air separation plants, an arrangement can also be made according to which the Plate condenser evaporator is divided into a group of several, preferably four plate packs in the vicinity of a central supply line for that to be condensed Medium with connections on the upper part of the side walls facing this supply line, other lower part also condensate drains are connected, which are discharged centrally the plate packs in a liquid bath of the medium to be evaporated with open spaces at the bottom and top for the medium to be evaporated with both sides closed side walls are arranged, so that with a sufficiently high setting of the liquid level, a thermosiphon circulation of the medium to be evaporated over the liquid bath is created.

For particularly high performance requirements, there is also a special one Combination of plate condenser evaporators advantageous. This is characterized by that two apparatuses arranged side by side in the circular cross-section of a column of plates and corrugated iron fixtures are stacked, with a free overflow of the unevaporated remainder of the upper apparatus via a standpipe and bottom collector supplied medium to be evaporated provided in the sump of the low pressure column is, in which the two lower apparatuses have an independent thermosiphon circuit of the medium to be evaporated are arranged forming, and wherein for supplying the to condensing medium from the pressure column from below to the superimposed Apparatus distribution lines and discharge of its condensate from the apparatus Manifolds provided down to a corresponding immersion cup of the pressure column are.

The generators of the corrugated iron fixtures are then in the gaps for the medium to be condensed or condensed in the area of the lateral inlet and outlet openings horizontally or obliquely downwards and vertically in between arranged, while the generators of the corrugated iron fixtures in the spaces for the medium to be evaporated run vertically throughout.

Corrugated sheet metal is an advantage for all constructions used, which consists of more or less evenly perforated sheet metal. To this Way a cross flow between the waves is made possible, which is an equalization the flow through the entire cross-section of the heat exchanger block, specifically to avoid dead flow areas.

Instead of perforated corrugated sheets are particularly advantageous in the Interstices for medium to be condensed corrugated sheets are used, their corrugations are offset in sections by shearing off the flanks, whereby the relationship is preserved at the wave heads.

It can also be useful that instead of corrugated iron fixtures with inclined generators wholly or partially those with horizontal generators are provided, each corresponding to the corrugated sheet metal components with vertical or connecting oblique generators. Finally, it is also possible to use further enlargement of the secondary exchange areas to be accommodated corrugated sheet metal fixtures to use, which are characterized in that the generators of the waves of the Corrugated iron used as installation material, each in levels corresponding to those on both sides Boundary planes of the corrugated iron are parallel, are designed to be wave-shaped. With Such a corrugated sheet of more or less uniformly perforated sheet metal is also advantageous Sheet.

Of course, any other combinations of Corrugated iron mounting material applied in the various spaces of the heat exchange block will.

With reference to the drawings, some embodiments of the Plate condenser evaporator according to the invention, for example, described in more detail will. It shows Fig. 1 is an oblique view of an apparatus with partially omitted front side wall, Fig. 2 is a section along the line II-II of the Fig. 1. Fig. 3 shows a section along the line III-III of Fig. 1, Fig. 4 partly a Section along the line IV-IV, partly a section along the line IV'-IV 'of FIG. 7, FIG. 5 a section along the line V-V of FIG. 4, FIG. 6 a section along the lines the line VI-VI of FIG. 4, FIG. 7 a plan view or section along the line VII-VII 4, FIG. 8 shows another embodiment corresponding to FIG. 5, FIG. 9 a Another embodiment according to FIG. 6, FIG. 10 shows a vertical section the line X-X of Figures 11, 11 is a plan view of a particular arrangement of a Plate condenser-evaporator according to the invention within a double rectification column an air separation plant, Fig. 12 to 14 different types of corrugated iron internals, 15 shows a vertical section along the line XV-XV of FIG. 16, FIG. 16 shows the plan of a further combined arrangement; and FIG. 17 is a side elevation of FIG. 16.

In the embodiment according to FIGS. 1 to 3, there is the heat-exchanging one Block made from panels 1 and corrugated sheet metal fixtures 2. A hood 3 is attached below, in which the condensed medium collects. Above is a steam collecting space 16 through the hood 4 is formed with overflow slots 5 in an overflow manifold 6 is provided.

The medium A to be condensed enters the supply manifold 7 on the upper part of the two side walls of the plate condenser-evaporator. Accordingly, a supply manifold 8 is provided for the supply of the medium to be evaporated at the lower part of the two side walls. The overflow collecting line 6 is connected to the supply collecting line 8 by the line 9. The medium B to be evaporated is fed to the feed line 8 through the collecting line 10. The evaporated medium emerges from the steam collecting space through nozzles 11 .

As can be seen from FIG. 2, the generatrices of the corrugated sheet metal fittings run in the area of the inlet nozzle 7 for medium to be condensed A diagonally downwards from both sides up to the middle, while corrugated iron fittings are installed downwards connect with vertical generators. The plate gap 2 a for to be condensed The medium is closed at the top by a sheet metal strip 12. Down can that however, condensing medium emerges freely and passes through the collecting space 13 the outlet connection 14 as condensate together with any residual gas from the condenser and is fed to appropriate further use.

According to Figure 3, the generators of the corrugated sheet metal fixtures run in the space 2 b for medium B to be evaporated in the area of the bottom of the two side walls arranged supply manifolds 8 from both sides obliquely upwards, while internals with vertical generators are then connected upwards. The gap 2 b is covered at the bottom by the sheet metal strip 15, but can go up the liquid medium to be evaporated can escape freely and pass through the overflow slots5 into the overflow manifold6, while the medium evaporated therefrom passes through the collecting space 16 and the outlet nozzle 11 withdrawn from the evaporator and appropriate further use is fed. In Fig. 2 and 3, the corrugated iron fixtures are with vertical generatrices made of sheet metal with 101 / o free hole cross-section, the compartments with bevels Generators are made of sheet metal with 23% free hole cross-section for better To achieve distribution. As can be seen, the length L of the block is essential greater than its height H.

Another particularly preferred embodiment is shown in FIGS 7 shown. Those parts which correspond to FIGS. 1 to 3 are identical Provided with reference numerals. The medium A to be condensed is supplied here through two elbows7a each into the supply manifolds7 on both sides. The discharge the condensate and, if applicable, residual gases are carried out through the bottom collector 20, 21 and 22 via the nozzles 20 a, 21 a, and 22a into the collecting line 23.

The medium B to be evaporated, on the other hand, is supplied through the collecting line 24 via the nozzles 25 a to 28 a into the bottom collectors 25 to 28. The overflow of the still liquid medium B to be evaporated takes place from the collecting line 6 through the line 29 back to the collecting line 24 .

According to FIG. 5, the intermediate space 2a for the medium A to be condensed is provided in the lower part with corrugated iron fittings due to a different floor design, the generators of which lead downwards at an angle to discharge the condensate and possibly residual gas into the floor collectors 20 to 22. Immediately above the soil collectors 20 to 22 , however, internals with vertical generators are carried out.

Accordingly, according to FIG. 6, the corrugated iron fittings in the Space 2 b for the medium to be evaporated B in the lower part, namely above the collector 20 to 22 for the medium A to be condensed, which are covered here, Corrugated iron fixtures with generators leading diagonally upwards in area 31.

The bottom collector 20 to 22 for the condensed medium and residual gas are in the area of the spaces 2 b for the medium to be evaporated Sheet metal strips 15 'covered. Conversely, the soil collectors 25 to 28 are for that too evaporating medium, which is supplied here, in the area of the spaces 2 a for the medium to be condensed covered by sheet metal strips 15 ".

As shown in Figure 8 and 9, for example, the perforated Corrugated iron fixtures with inclined generators each through those with horizontal generators should be replaced in full or in part.

In particular, the corrugated sheet metal components with vertical generators and especially those parts for the medium to be condensed can be advantageous be replaced by corrugated iron with flanks offset in sections by shearing, The cohesion at the shaft heads is preserved, as shown in detail in Fig. 13 can be seen.

In addition, the same corrugated iron fixtures can also be used with corrugated iron 14 are replaced, the wave-generating in planes that the mutual Boundary planes of the corrugated iron are parallel, are designed to be wave-shaped. Even here is a corresponding perforation of the base material to achieve more uniformity Cross flows appropriate.

Depending on the substances to be evaporated and condensed Media can also be any other combination of different corrugated sheet materials be applied. Depending on the properties of the media to be processed, one will choose the construction that has the greatest equipment performance on the one hand and on the other hand guarantees the least incrustation difficulties.

The plate condenser-evaporator according to the invention is of particular importance for the evaporation of oxygen through the condensation of nitrogen in air separation plants, with the aim of achieving particularly small temperature differences of 1 to 3 ° C between the two media for the lowest possible compression energy consumption arrives.

The arrangement of such plate condenser-evaporator z. B. in a Double rectification column of an air separation plant can be seen from FIGS. 10 and 11.

In Fig. 10 are the upper part of the respective lower pressure column 35 and the lower part of the above-arranged low-pressure column 36 shown, wherein the plate condenser-evaporator according to the invention in the sump 37 of the low-pressure column 36, i.e. arranged in an oxygen bath, as in the plan from FIG. 11 can be seen.

From the length l of the four around the central nitrogen supply line arranged blocks results in the total length L = 41, which is also their height H significantly exceeds.

The nitrogen line 38 leads from the pressure column 35 centrally above to the plate spaces connected all around via the claws 39 above 2a, the bottom on the same side by the claws 40 with the leads 41 connected for nitrogen condensate. The inner side walls 42 and the outer Side walls 43 of the blocks made of partition plates 1 and corrugated sheet metal liners 2 are in the remaining completed, so that the oxygen in the spaces 2 b perpendicular must rise and through the formation of vapor bubbles Thermosiphon circulation arises over the bathroom. The oxygen vapors escape upwards into the low-pressure column 36, from which liquid oxygen enters the sump. The mirror of the liquid Oxygen is expediently kept so high that the entire heating surface is filled with liquid is covered or a vigorous cycle is created over the bath.

The width of a gap 2a, 2b is 8 to 12 mm, depending on the size of the overall apparatus, so that a number of separating plates in the order of 100 pieces is normally used for a plate condenser-evaporator.

In Fig. 15 to 17 is a further embodiment for a combined Arrangement of the plate condenser-evaporator according to the invention shown.

With regard to the fact that usually in air separation plants Double rectification columns with a lower pressure column and an upper low pressure column can be applied, the nitrogen vapor coming from the pressure column condensing and the liquid oxygen produced in the bottom of the low-pressure column is evaporated must, on the one hand, there is great interest in taking this into account with advantage to accommodate the upcoming plate condenser-evaporator inside the column cross-section, on the other hand, however, to make the column as resilient as possible. For these reasons, it is particularly advantageous here to have two such apparatuses 50 and 51 to be arranged one above the other, each apparatus being an independent one Receives overflow for liquid oxygen (Bfl). The inflow of liquid oxygen takes place from one or more overflow beakers in the upper low-pressure column through the tubes 52, which are immersed in standpipes 53. At their lower end are the standpipes 53 are connected to the lower soil collectors 55 by pipes 54. from This rises from the thermosiphon effect of the liquid oxygen vapor bubbles forming through the corresponding spaces 2b of the block upwards, where the still liquid portion with separation of the vapor upwards over the side edges of the Blocks overflows freely and finally reaches the sump 57 of the low-pressure column. The oxygen level is expediently kept approximately at the level of the mark x. He can but with different column loading between a minimum level y and one Peak z fluctuate, which results in a considerable elasticity of the column operation results. If the oxygen level rises above the mark x, the result is automatically a throttling of the column output, since the steam bubbles from the lower Evaporators 50 have to overcome a correspondingly higher liquid column and hence the temperature difference between nitrogen and oxygen here decreases. At maximum column output, the oxygen level quickly returns to normal Stand back, making each vaporizer under optimal cycle conditions and maximum temperature difference between nitrogen and oxygen works.

The gaseous nitrogen A from the pressure column rises up through the lines 60 and passes through the branch lines 61 and 61 'into the lateral supply manifolds 7 and 7', which lead into the spaces 2a of the block of the plate condenser-evaporator (Fig. 15, left half). As described above, the nitrogen condensate A El collects in the middle bottom collectors 63 and 63 '. From here the condensate is fed back down through the lines 64 and 64 'and the downcomer 65 into a corresponding immersion cup of the pressure column. The construction of the corrugated sheet metal fittings otherwise corresponds to FIGS. 8 and 9.

The heat exchange block according to the invention is constructed in such a way that that the corresponding corrugated iron and also the partition plates, both preferably made of Aluminum, already with solder rolled on both sides with a correspondingly lower melting point getting produced. The initially loosely stacked block is then under brought the appropriate pressure in a salt bath, which is evenly accurate to the Temperature of the melting point of the solder, which is so much lower, that the sheet material does not melt at any point. That way will the entire block is soldered in one piece so that it is also able to make larger ones Differences in pressure, approximately from 5 to 50 at, both between the media and opposite to withstand atmospheric pressure. The connecting pieces and hoods are each with provided corresponding curvatures so that these are also pressure-resistant. After finished When soldering, great care must be taken to ensure that the salt is completely removed so that there are no signs of corrosion when the heat exchange block is put into operation appear.

Claims (13)

PATENT CLAIMS: 1. Plate condenser evaporator, especially for Gas and air separators, with corrugated iron fittings in each of the media rooms on both sides on flat plates that tightly separate the heat-exchanging media abut and form a solid block with these, and with devices for passage of the medium to be condensed essentially from top to bottom and of the medium to be evaporated Medium from bottom to top, characterized in that the block of vertical Plates (1) with corrugated sheet metal fittings (2) have a total length in Has the direction of the plate planes, which at least reaches the height of the block, but preferably by more than 5004. 2. Plate condenser evaporator according to claim 1, characterized in that the height of the block is at most 1 m, is preferably 400 to 600 mm. 3. Plate condenser evaporator according to claim 1 or 2, characterized in that at the upper open end of the separating plate spaces for the medium to be evaporated (B) along at least one outer longitudinal wall overflow slots (5) to an overflow manifold (6) are provided, which in the inlet line (8, 24) returns for the medium to be evaporated, while for the withdrawal of the evaporated Medium from the collecting space (16) located above the heat exchange block at least an outlet nozzle (11) is provided (Fig. 1 and 4). 4. Plate condenser evaporator according to claim 3, characterized in that the generatrices of the corrugated sheet metal fittings (2) between the plates (1) in the area of the lateral inlet openings (7, 8) diagonally upwards for the (B) to be evaporated or downwards for the one to be condensed Medium (A) are arranged, while upwards for the to be evaporated or downwards for the medium to be condensed corrugated sheet metal fittings with vertical generators connect (Fig. 2 and 3). 5. Plate condenser evaporator according to claim 3, characterized in that for the supply of the medium to be condensed (A) openings on the upper part of at least one side wall and for the supply of the medium to be evaporated (B) or for the discharge of condensate Bottom collectors (25 to 28 or 20 to 22) are provided with any residual gas, whereby in the intermediate spaces (2a) for the medium to be condensed (A) in the area of the lateral inlet nozzles (7, 7a) and below above the bottom collectors (25 to 28) for the medium to be evaporated (B) the generators of the corrugated iron internals are arranged obliquely downwards and vertically in the middle area, while the generators of the corrugated iron internals in the spaces (2b) for the medium to be evaporated (B) below above the bottom collectors ( 20 to 22) for the medium to be condensed (A) run obliquely upwards and vertically in the remaining part (Fig. 5 and 6). 6. Plate condenser evaporator according to claim 1 or 2, characterized in that it is divided into a group of several preferably four plate packs in the vicinity of a central supply line (38) for the medium to be condensed with connections (39) on the upper part of this supply line facing side walls (42), on the lower part of which also condensate drains (41) are connected, which are discharged centrally, with the plate packs in one Liquid bath of the medium to be evaporated with gaps open at the bottom and top (2 b) for the medium to be evaporated with side walls closed on both sides (42, 43) are arranged so that with a sufficiently high setting of the liquid level a thermosiphon circulation of the medium to be evaporated over the liquid bath is created (Fig. 10 and 11). 7. plate condenser evaporator according to claim 1 or 2, characterized characterized in that two arranged side by side in the circular cross section of a column Apparatus (50, 51) of plates (1) and corrugated iron fixtures (2) placed one above the other are, with a free overflow of the unevaporated remainder of the upper apparatus (51) via a standpipe (53) and bottom collector (55) to be evaporated Medium (Bff) is provided in the sump (57) of the low-pressure column, in which the two lower devices (50) an independent thermosiphon circuit of the to be evaporated Medium forming are arranged, and wherein for supplying the medium to be condensed from the pressure column from below to the superimposed apparatus (50, 51) distribution lines (60, 61, 61 ') and collecting lines for the discharge of its condensate from the apparatus (50, 51) (64, 64 ', 65) provided downwards to a corresponding immersion cup of the pressure column are (Figs. 15-17). B. Plate condenser evaporator according to claim 6 or 7, characterized in that the generators of the corrugated sheet metal fittings (2) in the spaces (2a) for the medium (A) to be condensed or condensed in the area of the lateral inlet and outlet openings are horizontal or inclined are arranged vertically downwards and in between, while the generatrices of the corrugated sheet metal fittings (2) in the spaces (2b) for the medium (B) to be evaporated run continuously vertically. 9. Plate condenser evaporator according to one or more of the claims 1 to 8, characterized in that the corrugated sheet used as installation material consists of more or less evenly perforated sheet metal (Fig. 12). 10. Plate condenser evaporator according to one or more of claims 1 to 8, characterized in that the Waves of the corrugated sheet metal used as installation material through wave sections Shear off the flanks are offset, the relationship at the shaft heads is preserved on both sides (Fig. 13). 11. Plate condenser evaporator after a or more of claims 1 to 8, characterized in that corrugated sheet metal with sheared, offset shaft sections only for the discharge of condensing gases with condensate downwards, i.e. in the lower part below the upper side inlet nozzle is used, while corrugated sheet metal made of perforated sheet metal is used for all remaining spaces, partly with inclined, partly with vertical generators. 12. Plate condenser evaporator according to one of claims 9 to 11, characterized in that instead of corrugated sheet metal built-in parts with inclined generatrices in the area of the lateral connecting pieces, in whole or in part those with horizontal generators are provided, each corresponding accordingly connect to the corrugated sheet metal components with vertical or inclined generators. 13. Plate condenser evaporator according to one or more of claims 1 to 9, characterized in that the generators of the waves as installation material used corrugated iron in each case in levels that the mutual boundary levels of the corrugated sheet are parallel, are designed to be wave-shaped (Fig. 14).