AN EVAPORATOR PLATE HEAT EXCHANGER

Abstract

The invention is directed to an evaporator plate heat exchanger comprising a water supply (1) and a water discharge (2) and a stack (4) of injected moulded frames (5) and heat exchange sheets (6), wherein the stack has two ends (7, 8) and at least four sides (9, 10, 11,12). The stack (4) has alternating first (13) and second (14) spaces between the heat exchange sheets (6). The stack (4) comprises a first enclosed space (15) at one side of the stack (4) which is fluidly connected to the first spaces (13) and not fluidly connected to the second spaces (14). The first enclosed space (15) is fluidly connected to the water supply (1).

Claims

1. An evaporator plate heat exchanger comprising a water supply and a stack of injected moulded frames and heat exchange sheets, wherein the stack has two ends and at least four sides, wherein the stack has alternating first and second spaces between the heat exchange sheets, the stack further comprises a first enclosed space at one side of the stack which is fluidly connected to the first spaces and not fluidly connected to the second spaces and wherein the first enclosed space is fluidly connected to the water supply.

2. An evaporator plate heat exchanger according to claim 1, wherein the stack further comprises a second enclosed space at the opposite side of the stack which is fluidly connected to the first spaces and not fluidly connected to the second spaces and wherein the second enclosed space is fluidly connected to a water discharge.

3. An evaporator plate heat exchanger according to claim 1, wherein the frame and the heat exchange sheet are comprised in a heat exchange plate and wherein the heat exchange plate is an insert moulded work product wherein the heat exchange sheet is the insert of the insert moulded work product.

4. An evaporator plate heat exchanger according to claim 3, wherein the stack comprises alternatingly stacked first heat exchange plate and differently shaped second heat exchange plate.

5. An evaporator plate heat exchanger according to claim 1, wherein the first enclosed space is formed by openings in the injected moulded frames and wherein the resulting two open ends are closed by a wall as present in closed end frames.

6. An evaporator plate heat exchanger according to claim 1, wherein the first enclosed space is formed by a box shaped part having an open side and wherein the box shaped part is fixed to the first side of the stack such that the open side faces the first side of the stack.

7. An evaporator plate heat exchanger according to claim 1, wherein the first enclosed space is fluidly connected to the first spaces by means of elongated and parallel openings or parallel rows of smaller openings.

8. An evaporator plate heat exchanger according to claim 1, wherein the heat exchange sheet is an aluminium sheet.

9. An evaporator plate heat exchanger according to claim 1, wherein two consecutive heat exchange sheets in the stack have facing sides to first space and wherein the facing sides are provided with a layer of a hydrophilic material.

10. An evaporator plate heat exchanger according to claim 1, wherein the frame of the heat exchange plate is made of acrylonitrile butadiene styrene (ABS), Nylons (polyamides; PA), polypropylene (PP), polyethylene (PE) or polyvinyl chloride (PVC).

11. An evaporator plate heat exchanger according to claim 1, wherein the frame has a square shape or a rectangular shape.

12. An evaporator plate heat exchanger according to claim 1, comprising multiple stacks of interconnected injected moulded frames, each stack provided with closed end frames.

13. An evaporator plate heat exchanger according to claim 12, wherein the stacks have the same number of interconnected injected moulded frames.

14. An evaporator plate heat exchanger according to claim 1, wherein the number of interconnected frames is between 15 and 50.

15. An evaporator plate heat exchanger according to claim 14, wherein the frame has a square shape or a rectangular shape resulting in a box shaped stack and wherein the stacks are positioned in line such that their respective sides are in line and wherein a second side of the stack is connected to an header for a first gas flow and connected to a header for a second gas flow and wherein a fourth side of the stack is connected to a header for the second gas flow and to a header for the first gas flow.

16. An evaporator plate heat exchanger according to claim 15, wherein the headers are comprised of interconnected modular elements of the same size and shape.

17. An evaporator plate heat exchanger according to claim 16, wherein the modular element is a hollow cuboid shaped gas flow element, each gas flow element having an interior space six open faces, eight vertices and twelve edges interconnecting the eight vertices, wherein the four edges of at least one open face of a first gas flow element of one header is connected in a gas tight manner to four edges of an open face of a second hollow cuboid shaped gas flow element of the same header at their respective connecting open faces and, wherein at their respective connecting open faces the four edges of the open face of the first gas flow element is connected in a gas tight manner to four edges of the open face of the second hollow cuboid shaped gas flow element by means of a connecting frame, wherein the connecting frame is provided with means to connect to the four edges of the open face of the first gas flow element and is provided with connecting means to connect to the four edges of the open face of the second hollow cuboid shaped gas flow element.

18. An evaporator plate heat exchanger according to claim 17, wherein at one side of the stack or stacks the hollow cuboid shaped gas flow elements of one header are connected to the hollow cuboid shaped gas flow elements of the other header.

19. An evaporator plate heat exchanger according to claim 18, wherein the hollow cuboid shaped gas flow elements of one header are connected to the hollow cuboid shaped gas flow elements of the other header and wherein in the connection between the two headers valves are present allowing to fluidly connect and disconnect the connected headers.

20. Use of an evaporator plate heat exchanger according to claim 1, wherein the first enclosed space contains pressurised water.

Description

[0028] The invention shall be illustrated making use of FIGS. 1-11.

[0029] FIG. 1 shows an expanded stack (4) of injected moulded frames (5) provided with insert moulded heat exchange sheets (6). In FIG. 2 the frames (5) are connected to form a stack (4) oriented in its preferred horizontal direction. The frames (5) are provided with openings (17) which will form the first and second enclosed spaces (15,16) when the frames (5) are stacked and connected. At both ends of the stack end frames (2a,2b) are provided which do not have these openings (17) and therefore enclose the first and second enclosed spaces at these ends of the stack (4).

[0030] Between the frames (5) first (13) and second (14) spaces are formed as shown in FIG. 2. As can be seen in FIG. 2 the first spaces (13) are open at a upper part of side (10) and the second spaces (14) are open in a lower part of side (10). This allows to position a gas header (not shown) for separate gas flows in first and second spaces above each other as shown in FIGS. 6 and 7 and 11. The dimensions in FIG. 2 of the thickness of a frame (5) is drawn not to scale such to more clearly illustrate the positioning of the openings in side wall (10). To achieve these alternating openings for first and second spaces the frames (5) are suitably of alternating different designs. These alternatingly stacked first heat exchange plate (16a) and differently shaped second heat exchange plate (16b) are shown in FIG. 3 each comprising of a heat exchange sheet (6). A further difference is that in frames (16a) of the stack (4) the first and second enclosed spaces (15,16) are connected to the first space (13) by channels (20a,20b). In FIG. 3 the frames (16a,16b) are shown with reference numbers (9,10,11,12) to show which side of the frames correspond with the side of the stack (4). Ridges (12a) and (10a) are present to connect to a header as shown in FIG. 11.

[0031] In FIG. 2 a water supply (1) and a water discharge (2) is drawn as conduits connected to enclosed first and second enclosed spaces (15,16) respectively. The first enclosed space (15) is fluidly connected to water supply (1) and the second enclosed space (16) is fluidly connected to water discharge (2). These fluid connections may be made by drilling a hole in a connected stack of frames from sides (9) and (11) until the enclosed spaces are reached.

[0032] FIG. 4 shows the exterior of a stack (4) of interconnected frames (5) to which stack a box shaped part (18) is added to form the first enclosed space (15) at the upper side (9) of the stack. The open side of the box shaped part (18) faces side (9) of the stack (4). Further a box shaped part (19) is added to form the second enclosed space (16) at the lower side (11) of the stack (4). The open side of the box shaped part (19) faces side (11) of the stack (4). The shape of the box shaped part may in fact be any shape which has an open side suited to be connected to the sides of the stack.

[0033] FIG. 5 shows a cross-sectional view AA of FIG. 4 in a first space (13). A frame (5) with an insert moulded heat exchange sheet (6) is shown. In the box shaped part (18) is shown above a slit like opening (20) to the first space (13). Further a slit like opening (20c) is shown to connect first space (13) with second enclosed space (16).

[0034] FIG. 6 shows in a simplified manner how the stacks of FIGS. 1-5 may be combined with headers. A stack (4) is shown from one end (7). At the upper end of side (10) a third gas flow header (24) is shown for supplying a first gas flow (solid line) to the first spaces (13). At the upper end of side (12) a first gas flow header (26) is shown for supplying a second gas flow (dotted line) to the second spaces (14). At the lower end of side (12) a fourth gas flow header (27) is shown for collecting gas from the first spaces (13). At the lower end of side (10) a second gas flow header (25) is shown collecting gas from the second spaces (14). These headers are obviously further connected to an gas supply and an gas discharge system not shown in this figure.

[0035] FIG. 7 shows three stacks (21,22,23) of square frames (5) wherein the stacks (21,22,23) have the same dimensions. The stacks (21,22,23) are positioned in line such that the respective sides (9,10,11,12) are in line. The closed end frames of one stack (21) thus faces the closed end frame of the next stack (21a) in the row of stacks. Further the first enclosed spaces and second enclosed spaces of the four stacks (21,21a, 22,23) are separate spaces and thus not connected to form a single space. Sides (10) and (12) of all stacks (21, 21a, 22,23) are provided with headers (24,25,26,27) as shown in FIG. 6. Each header is, in contrast with the stacks (21,21a,22,23), comprised of a common space which allows for example to supply the first gas flow (shown as the solid line in FIGS. 6 and 7) to the separate first spaces of the three stacks (21,21a,22,23) from a common header (26) as in FIG. 6.

[0036] It is preferred that such a header is comprised of interconnected modular elements (28) of the same size and shape. In this way one can easily assemble different sized headers when combining different numbers of such standardised stacks (21,21a,22,23). In this figure one header is obtained by combining four modular elements (28). It is also possible that per stack length more modular elements are used such that along side (10) of one stack (21) 2 to 4 modular elements are present. Such modular elements (28) suitably also allow that headers (24) and header (25) are connected and that header (26) and header (27) are connected to the stack. For example by ridges (10a, 12a) of FIGS. 3a and 3b. Headers (24) and (25) may be fluidly connected and disconnected by means of a valve. This makes the illustrated plate heat exchangers especially suited to be used in the process described in WO2016/206714.

[0037] FIG. 8 shows a modular element (28) which may be used as part of the headers shown in FIGS. 6 and 7. The modular element (28) is suitably a hollow cube shaped gas flow element (30) as shown in this figure. The gas flow element (30) has an interior space (34), six open faces (35), eight vertices (36) and twelve edges (37) interconnecting the eight vertices (36).

[0038] FIG. 9 shows a connecting frame (38) provided with an opening (39) and four edges (40). Along the edges (40) extrusions are seen directed in both directions perpendicular to the plane of the frame. These extrusions are suitably cantilever snap-fit connections (41) which can connect to an edge (37) of the gas flow element (30) as seen in FIG. 3.

[0039] FIG. 10 shows a detail of a modular member of FIG. 8 at one of its vertices (36) wherein one open face is provided with a connecting frame (38) and a neighbouring open face is provided with an enclosing wall element (45). Both the connecting frame (38) as the enclosing wall element (45) are provided with numerous protrusions (46) in a perpendicular direction with respect to the plane of the connecting frame (38) or plane of the enclosing wall element (45). The protrusions (46) are provided with a sharp edge (47) at its end which are dimensioned such that they form a cantilever snap fit connection with the edge (37). As shown the location of the protrusions (46) of the connecting frame (38) and the enclosing wall element (45) are not at the same positions along the edges of these elements. This makes it possible that neighbouring open faces of a modular member can be provided with connecting frames (38), enclosing wall elements (45) or other elements by a snap fit connection on its common edge (37).

[0040] Thus preferably the modular element is a hollow cuboid shaped gas flow element, each gas flow element having an interior space, six open faces, eight vertices and twelve edges interconnecting the eight vertices, [0041] wherein the four edges of at least one open face of a first gas flow element of one header (24,25,26,27) is connected in a gas tight manner to four edges of an open face of a second hollow cuboid shaped gas flow element of the same header at their respective connecting open faces and, [0042] wherein at their respective connecting open faces the four edges of the open face of the first gas flow element is connected in a gas tight manner to four edges of the open face of the second hollow cuboid shaped gas flow element by means of a connecting frame, [0043] wherein the connecting frame is provided with means to connect to the four edges of the open face of the first gas flow element and is provided with connecting means to connect to the four edges of the open face of the second hollow cuboid shaped gas flow element.

[0044] Preferably at one side of the stack or stacks the hollow cuboid shaped gas flow elements of one header are connected to the hollow cuboid shaped gas flow elements of the other header. When a row of multiple gas flow elements are connected to a row of stacks or to another row of gas flow elements it may happen that because of manufacturing tolerances no connection is possible. This may be mitigated by using a gas tight bellow between one or more of the stacks and/or between one or more of the gas flow elements which bellows allows a varying distance between the stacks and/or gas flow elements.

[0045] Preferably the hollow cuboid shaped gas flow elements of one header are connected to the hollow cuboid shaped gas flow elements of the other header and wherein in the connection between the two headers valves may be present allowing to fluidly connect and disconnect the connected headers.

[0046] Such a connected header is shown in FIG. 11 showing a header (26) composed of five fluidly interconnected gas flow elements (30) and a header (27) composed of five fluidly interconnected gas flow elements (30). The header (26) and (27) are open to the viewer and closed at its not visible back wall. The open side will be connected to side (12) of the stack (4) or stacks (4). At their end the headers (26,27) are connected to a gas inlet flow element (42) and a gas outlet element (43) which may be connected to gas supply conduit and gas discharge conduit. A motor (45) may operate a valve (46) to cut off the gas supply from gas inlet flow element (42). A motor (47) may operate valves (48) fluidly connecting and disconnecting header (26) and header (27)

[0047] The hollow cuboid shaped gas flow element is suitably made of a polymer. Preferably the hollow cuboid shaped gas flow element is a single injected moulded work product. The connecting frame is also preferably made of a polymer and is preferably a single injected moulded work product.

[0048] The dimensions of the hollow cuboid shaped gas flow element may vary. When they are used in combination with a plate heat exchanger it is preferred to use elements having a minimal dimension of an edge of 0.1 m and a maximum dimension for an edge of 0.3 m being the distance along the edge between two vertices.

[0049] The hollow cuboid shaped gas flow element, the connecting frame, the rectangular shaped frame and/or the rectangular shaped closed frame may be made of a polymer. Preferably a polymer which may be used in injection moulding. Suitable polymers are polypropylene (PP) and/or polyoxymethylene (POM).

[0050] The connecting frame preferably has about the same dimensions as the sides of the hollow cuboid shaped gas flow element. The connecting frame is either closed to provide for the partition or provided with an opening at its centre to allow a fluid communication between the first and second hollow cuboid shaped gas flow element. This open space is preferably about the same shape as the open face of the hollow cuboid shaped gas flow element. The remaining edges of the frame are provided with the means to connect to the four edges of the open face of the first gas flow element and provided with connecting means to connect to the four edges of the open face of the second hollow cuboid shaped gas flow element.