WO1992000129A1

WO1992000129A1 - Column body to take plate-type heat exchangers

Info

Publication number: WO1992000129A1
Application number: PCT/DE1991/000511
Authority: WO
Inventors: Hussein Morsy; Karl Jörg BODLER; Wolfgang Hribar; Hans Sadowiak; Leo Schulz
Original assignee: Dvt Büro Für Anwendung Deutscher Verfahrenstecknikh. Morsy
Priority date: 1990-06-22
Filing date: 1991-06-21
Publication date: 1992-01-09
Also published as: DE4019991A1

Abstract

A column body (K1 to KN) for a column supported by a frame is made up, to take a plate-type heat exchanger (25), of at least two and preferably four hollow cylindrical segments (51, 52, 53, 54) between which are enclosed axially extending webs (50) on the plate-type heat exchanger which sub-divide the jacket space of the column body in relation to the flow channels (34, 35) of the enclosed plate-type heat exchanger and at the same time act as its supports, whereby to the annular front sides of the composite cylindrical segments (51, 52, 53, 54) are allocated flange components (60, 61, 62, 63) of which first ones (60) serve to form the column bodies into a column and others (61, 62, 62') radially limit the casing space of the column body divided by the axial webs (50).

Description

Column body for holding plate heat exchangers

The invention relates to a column body for receiving heat exchangers, with flange and support elements for the purpose of releasable connection of a plurality of column bodies to a column and this with a supporting structure.

Known column bodies combined into a column in the form of cylindrical jacket-shaped containers, in particular for the desalination of sea water according to the so-called multi-effect evaporation method, enclose pressure-tight vertical tube bundles arranged between the end flanges and are equipped with the necessary accessories. and derivatives for the process medium connected; see. DE-PS 23 34 481.

Since only a maximum of fifteen pressure stages can be practically realized with such tubular heat exchangers for static reasons, plate heat exchangers with which up to 50 pressure stages and more can be practically implemented are increasingly being used instead of the tubular heat exchangers. The yield in the desalination of seawater using the multi-effect evaporation method is known to be dependent on the number of available evaporation stages within an available temperature difference due to the physical conditions.

It is known to plate heat exchangers of this type in a one-piece rectangular pressure housing which is internally is arranged half of a supporting frame, in the form of so-called slide-in packages, in order to enable their exchange, for example for maintenance purposes; see. DE 32 39 816-A1.

Such plate heat exchangers consist of individual, embossed heat exchanger plates which have ribs which are aligned in the longitudinal and transverse directions and are uniformly arranged and which are in pairs mirror-image one on top of the other in such a way that the beads oriented in one direction are tube-like channels and the beads oriented in the other direction delimit gap-like channels through which, depending on the application of the heat exchanger plates as preheater or as falling film evaporator, either steam or sea water or sea water or steam flow. These mutually identical heat exchanger plates are combined into packages and form a kind of packing within the column and are required in large numbers in view of the large number of stages. Since the individual heat exchanger plates are relatively thin, that is to say statically unstable, they must be fixed in their mutual arrangement and in their arrangement within the column body by special measures. In the known design of the heat exchanger plates in the form of slide-in packages, however, detachable seals are required between the individual pressure stages, whereby the further advantage of such plate heat exchangers is lost, that instead of the clamp connections to be sealed, only welded connections for the cohesion of the individual Plate elements are used.

The invention is therefore based on the object of a new column body as an interchangeable component

Column for the implementation of n heat processes

Inclusion of plate heat exchangers as so-called To create a welded construction which can be joined together to form columns of any size and which has separate feed spaces for the flow channels of the plate and plate heat exchangers on the gap and pipe side, which are without additional seals.

This object is achieved in that each column body for receiving a plate heat exchanger consists of at least two, preferably four, cylindrical shell segments, between which are included webs which extend in the axial direction and which enclose the jacket space of the column body with respect to the flow channels of the Subdivide enclosed plate heat exchanger and at the same time serve as its support elements, and that flange elements are assigned to the annular end faces of the assembled cylinder shell segments, from their first flange elements the connection of the column body to a column and further flange elements to limit the radial direction through the axial webs serve divided shell space of the column body.

According to a further feature of the invention, of the further flange elements, the flange elements lying on the inlet side of the column body are designed as rectangular receiving containers, while the flange elements arranged on the outlet side are formed in two parts and include an annular opening, the flange elements forming a receiving container between Plate heat exchanger and first flange elements and the two-part flange elements are arranged between cylinder shell elements and plate heat exchanger or between plate heat exchanger and lower first flange elements. Baffle plates are advantageously arranged downstream of the pipe sockets of the column body which feed the process medium.

Further features of the invention result from the subclaims.

Due to the design of the column body according to the invention, this serves as a pressure vessel for the plate heat exchanger enclosed by it, all feed spaces for the process medium being joined to the gap-side or tube-side channels exclusively by welded connections, so that additional seals are completely eliminated . The process temperatures and pressures can therefore be increased significantly. Also an exchange of such column bodies according to the invention, e.g. possible for maintenance purposes in the simplest way, without having to insert new seals inside the column body. Sealing bodies are only located between the individual column bodies and their associated compensators in order to absorb unavoidable thermal expansions within the column.

The inventive design and subdivision of the further flange elements assigned to the discharge side of the column body into annular segments and into trapezoidal segments, of which the annular segments between the inner wall of the column body and the heat exchanger and the trapezoidal segments between the heat exchanger and the first flange ¬ elements are extremely advantageous, since in this astonishingly simple manner on the outlet side of the plate heat exchanger enclosed by the column body, an extremely large volume with respect to the volume of its gap-side channels for the steam-brine leaving the plate heat exchanger Mixture is created in the form of an aerosol, so that by the this caused a strong change in the flow rate of the steam-brine mixture, the droplets located there precipitate out and can remain in the process.

Another advantage of the design of the column body according to the invention is that all the essential weld seams for producing such a column body can be attached from the outside. It is therefore easy to check the required weld connections for their strength and tightness from the outside.

The invention is described below with reference to an embodiment shown more or less schematically in the drawing. Show in detail

FIG. 1 shows a perspective illustration of a plurality of column bodies joined together to form a column on a support frame,

FIG. 2 shows a cross section through a column body of the column along the line II II according to FIG. 1,

FIG. 3 shows a longitudinal section through a column body along the line III III in FIG. 2,

FIG. 4 shows a longitudinal section through a column body according to line IV IV in FIG. 2,

5 shows an enlarged illustration of a partial section at the junction of two column bodies for a column according to FIG. 1 and Figure 6 is a perspective view of part of a plate heat exchanger enclosed by a column body.

1 shows, as shown in FIG. 1, a column 12 which is assembled from individual column bodies K1 to Kn which are identical to one another, between each of which there is a compensator 15 for the purpose of compensating for thermal expansions is located, via pipeline connections 16 to 19 in the exemplary embodiment selected here, the column bodies are supplied as parts of a sea water desalination plant to the heat exchangers enclosed by the column bodies, sea water - raw water and steam, and vapors and distillate - pure water - are removed .

Since this is not important for the understanding of the invention, these parts are not shown and described in detail.

Of course, two or more columns can also be assigned to a supporting structure.

A plate heat exchanger 25 enclosed by a column body is shown in FIG. This consists of mutually identical, embossed shaped plates 30. Each shaped plate has beads 32 and 33 which represent elevations and depressions. In each case two shaped sheets 30 embossed in this way are mirror-inverted one on top of the other by means of first weld seams formed as roller weld seams on their opposite, unembossed edge regions, the plate elements of which plate-like openings - gaps 35 - form gap-like openings with their mutually facing surfaces. Each plate pair is juxtaposed with an adjacent plate pair. The second welding seams - referred to as the front flat seam - connecting the adjacent edges, which are referred to as forehead butt joints, are firmly and pressure-tightly connected such that the mutually facing surfaces of the individual plate pairs form tubular openings 34. As FIG. 6 shows, the individual plate elements and the plate pairs formed therefrom are arranged in such a way that the openings on the gap and pipe side for the heat-exchanging media - here raw water and steam - are arranged at an angle to one another. The individual plate pairs joined together to form a stack are held by so-called comb plates (cf. DE 39 24 581-A1). A side plate 36 is welded to each of the outer shaped sheets 30 of the stack, and webs 50 are welded to their two opposite end regions. There are therefore four webs 50 per plate heat exchanger 25, each of which extends over the entire edge length of the stack and, in cooperation with the column body to be described, bring about a fluid-free, seal-free separation between the gap and tube sides of the stack.

Since these plate elements are also not the subject of the invention, a detailed description and representation of the plate heat exchanger is also omitted here.

A column body having the shape of a cylinder section for the seal-free reception of a plate heat exchanger will now be described in detail with reference to FIGS. 2 to 4.

As can be seen in particular in FIG. The axial webs 50 collapse with respect to the cross-section of the column body in the radial direction, which in the present exemplary embodiment consists of four cylinder shell segments which are essentially identical to one another. _ Q _ serve. The flange elements 61, which are upper in relation to FIG. 3, form a rectangular receptacle 65 for a knitted fabric 64 which distributes raw water and which is arranged above the gap-side channels 35 (FIG. 6) of the plate heat exchanger 25.

The lower - drainage side - flange elements in relation to FIG. 3 are formed in two parts and consist of an annular part 62 and a trapezoidal part 62 (FIG. 2). The circular parts each directly engage the inner wall of the column body formed from the cylindrical shell segments, while the trapezoidal parts, as shown in FIG. 3, are arranged lying between the heat exchanger and flange 60; see. also FIG. 2. Here, the webs 50 and the flange elements 60 limit the flow channel for the tube-side flow channels 34 of the plate heat exchanger 25, while the gap-side channels 35 serving the passage of the raw water - brine - through the flange elements 61 and through the side plates 36 of the plate heat exchanger 25 and the lower flange elements 62 and 62 ', which include an annular opening 63.

As can be seen from FIGS. 2 to 4, the flange elements 62 and 62 'in connection with the webs 50 and the side plates 36 on the outlet side of the plate heat exchanger 25 delimit a relatively large-volume flow space which communicates with the outlet connections 58 and which extends on both sides of the plate heat exchanger over its entire edge length. When the aerosol (steam-brine mixture) emerges, it experiences a speed reduction as a result of this increase in volume, so that droplets contained in the aerosol precipitate out and can remain in the process since they are fed directly to the subsequent temperature and pressure stage. - 8 - th 51, 52, 53 and 54 is formed, which are enclosed between the ends of the webs facing away from the heat exchanger in such a way that the cylinder shell segments complement each other to form a cylinder section, via weld seams 56 from the outside Cylinder shell segments with the webs 50 and thus connected to each other firmly and pressure-tight. The webs 50 thus simultaneously serve as supporting elements for the plate heat exchanger 25 described above.

Instead of four cylinder shell segments, two such cylinder shell segments can be used if the plate heat exchanger is designed accordingly.

In the areas of the cylinder shell segments in which the above-mentioned feed and discharge lines terminate, connecting pieces 57 and 58 are provided, with, as is shown in particular in FIG. 2, the gap side - here carrying a steam-brine mixture of plate heat exchanger 25 are assigned two opposite connecting pieces 58. Furthermore, tabs 59 are welded to the outer jacket surfaces of the cylinder shell segments facing the support frame 11 in the installed state, which serve to connect the column bodies to the support frame 11. In the present exemplary embodiment, these are the cylinder shell segments 51 and 53 according to FIG. 2.

The annular end faces of the cylinder shell segments joined together in the manner described above are each assigned flange elements (see FIGS. 3 and 4), of which the first flange elements 60, which are directly adjacent to the end faces, connect the column bodies to form a column serve (see FIG. 5), while further flange elements 61 and 62 or 62 'serve to radially limit the shell space of the column body divided by the axial webs 50 - 1 0 -

In order to achieve a good distribution of the steam to be supplied in each case to the inlet surface of the plate heat exchanger 25, a baffle plate 6 is connected downstream of the connecting piece 57 of each column body.

All the flange elements mentioned above are also firmly and pressure-tightly welded to one another and to the cylinder shell segments.

As FIG. 5 in particular shows, the compensator 15 inserted between two mutually facing end faces of the column body is releasably connected to its flange rings 66 with the interposition of a seal 67 by means of a loose flange 68 with the flange elements 60 of the column body by screws 69. The bellows-like compensator, provided with reinforcing rings 70, is made of pressure- and heat-resistant material (e.g. PTFE) and also encloses the discharge and inlet side of two adjacent column bodies in a pressure-tight manner.

As is immediately apparent from the above description in conjunction with the drawing, the completely welded plate heat exchanger is likewise pressure-tightly connected to the column body solely by welded connections and all flow channels within the column body are also pressure-tightly welded. Each column body forming a pressure and temperature stage of the heat exchanger column is therefore constructed without any seal, so that it functions reliably over long operating times even under difficult operating conditions.

Such a column body can be removed simply by loosening the screws 69 of the flange connection. as possible by loosening the connection of the tabs 59 between the column body and support frame. Maintenance and cleaning work can therefore be carried out in the simplest way. Since seals are missing from the column body, cleaning agents which dissolve lime and silicate can be passed through the entire column even without removing the column body, so that in particular cleaning work can be carried out at any time if necessary.

Claims

- 12 patent claims

1. Column body for receiving heat exchangers, with flange and support elements for the purpose of releasable connection of several column bodies to a column and this with a supporting structure, characterized in that each column body (Kl to Kn) for receiving a plate heat exchanger (25) consists of at least two, preferably four, cylindrical shell segments (51, 52, 53, 54), between which are enclosed webs (50) which extend in the axial direction and which cover the jacket space of the column body with respect to the flow channels (34, 35 ) of the enclosed plate heat exchanger and at the same time serve as its supporting elements, and that the circular end faces of the assembled cylinder shell segments (51, 52, 53, 54) each

Flange elements (60, 61, 62, 62) are assigned, of which first flange elements (60) connect the column body to a column and further flange elements (61, 62, 62 ') the radial limitation of the axial webs (50 ) divided

Serve jacket space of the column body.

2. Column body according to claim 1, characterized in that ¬ indicates that the flange elements lying on the inlet side of the column body (61) from the further flange elements are formed as a rectangular receiving container (65) are formed in two parts (annular 62, trapezoidal 62 ') and the flange elements (62 and 62) arranged on the outlet side and enclose an annular opening (63).

3. Column body according to Claims 1 and 2, characterized in that the flange elements (61) forming a receptacle (65) between the plate heat exchanger (25) and first flange elements (60) and the two-part flange elements (annular 62, trapezoidal) ¬ shaped 62- ^* ) between the cylinder shell elements (51, 52, 53, 54) and plate heat exchanger (25) or between plate heat exchanger and lower first flange elements (60).

4. Column body according to claims 1 to 3, characterized in that the pipe connection (57) feeding the process medium of the column body is followed by baffle plates (6).

5. Column body according to claims 1 to 4, characterized in that the connecting elements of the column body with the supporting frame (11) serving support elements (59) on the outer wall of at least one, preferably two, cylindrical shell segments (53) are arranged.

6. Column body according to claims 1 to 5, characterized in that a compensator (15) is releasably fastened between the facing end faces of two column bodies (K1, K2).

7. Column body according to claims 1 to 6, characterized in that all connections between cylinder shell elements (51, 52, 53, - 1 -

54) and support and flange elements (50, 60, 61, 62, 62) are welded connections (56).

8. column body according to claims 1 to 3, characterized g e k e n n z e i c h n e t that two each

Pipe sockets (58) are assigned to the jacket spaces of the column body (K) assigned to the gap side (34) of the plate heat exchanger (25).

9. Column body according to claims 1 to 3, characterized in that the jacket side assigned to the outlet side (pipe socket 58) of the plate heat exchanger (25) enclosed by the column body (k) has a larger volume than the jacket space assigned to the inlet side (65) having.