HEAT EXCHANGER PLATE, PLATE HEAT EXCHANGER AND WATER TREATMENT SYSTEM

Description

[0001] The invention relates to a plate heat exchanger and a water treatment plant. State of the art

[0002] Plate heat exchangers (PHEs) are known from the prior art. These comprise at least one heat exchanger plate between a first fluid chamber and a second fluid chamber, whereby heat can be transferred from a fluid in the first fluid chamber to a fluid in the second fluid chamber.

[0003] The document EP 1 508 016 A1 discloses a plate heat exchanger according to the preamble of claim 1.

[0004] The publication SE 528 143 C2 discloses a plate heat exchanger.

[0005] The document US 10 352 597 B2 discloses an evaporator for a heat pump, wherein the evaporator is designed as a plate heat exchanger.

[0006] The publication WO 2008 / 024 066 A1 discloses a plate heat exchanger.

[0007] The publication US 2016 / 320 141 A1 discloses a plate heat exchanger. Water treatment systems that operate using mechanical vapor compression distillation (MVCD), for example, and are used in seawater desalination plants, but also for drinking water treatment for individual consumption points, can incorporate such a plate heat exchanger as an evaporator-condenser unit.

[0008] Phase changes such as evaporation and condensation can lead to a significant increase in heat transfer compared to pure convection of fluids, where only the temperature of the medium is changed. In shell-and-tube heat exchangers (SHEs) used as condensers, this effect can be used to vary the effective condenser area during operation. By varying the fill level, the wetted surface is shielded from the gas phase and thus from condensation. In distillation processes, however, non-condensable components always accumulate on the condenser side, significantly reducing the condensation performance. These non-condensable components, which can also be referred to as inert gases, can be removed from the outside on the condenser side of shell-and-tube heat exchangers. Due to the compact design, this is not easily possible in plate heat exchangers. Disclosure of the invention

[0009] An object of the invention is to provide an improved plate heat exchanger and an improved water treatment plant.

[0010] This object is achieved with the plate heat exchanger according to claim 1. Advantageous embodiments are specified in the dependent patent claims.

[0011] A plate heat exchanger has at least one heat exchanger plate, a front plate, and an end plate. Furthermore, the plate heat exchanger has at least one first fluid chamber and at least one second fluid chamber, wherein each heat exchanger plate is arranged between a first fluid chamber and a second fluid chamber. The heat exchanger plate has a first supply opening, a second supply opening, a first discharge opening, and a second discharge opening. Furthermore, the heat exchanger plate has an inert gas discharge opening. The inert gas discharge opening can be used to remove non-condensable components during operation of a heat exchanger. First seals in the first fluid chamber separate the second supply opening and the second discharge opening from the first fluid chamber.Second seals in the second fluid chamber separate the first supply opening, the first discharge opening and the inert gas discharge opening of the heat exchanger plate from the second fluid chamber.

[0012] The volume flow through the inert gas discharge opening corresponds to a maximum of one-tenth, in particular a maximum of one-hundredth, of the volume flow supplied through the first supply opening. The volume flow discharged through the inert gas discharge opening can be adjusted by means of a pump. The volume flow can vary greatly due to different concentrations of inert gas in the vapor phase.

[0013] The heat exchanger plate can be configured such that the first supply opening, the second supply opening, the first discharge opening, and the second discharge opening are each arranged in different corner regions of the heat exchanger plate. The heat exchanger plate can be substantially rectangular. This means that the heat exchanger plate has four sides arranged such that angles of between 80 and 100 degrees exist between the sides. Here, too, the first supply opening, the second supply opening, the discharge opening, and the second discharge opening can each be arranged in different corner regions of the heat exchanger plate.

[0014] In one embodiment of the plate heat exchanger, the inert gas discharge opening comprises a slotted hole. The first supply opening, the second supply opening, and the second discharge opening are round. This can improve the flow of the inert gas.

[0015] In one embodiment of the plate heat exchanger, the inert gas discharge opening and the first discharge opening are designed as a common opening in the heat exchanger plate. This enables more flexible operation. The common opening can, in particular, be designed as an elongated hole.

[0016] In one embodiment, the plate heat exchanger further comprises a first heat exchanger supply opening, a second heat exchanger supply opening, a first heat exchanger discharge opening, a second heat exchanger discharge opening and a heat exchanger inert gas discharge opening, wherein the first heat exchanger supply opening is connected to the first supply opening or the first supply openings, the second heat exchanger supply opening is connected to the second supply opening or the second supply openings, the first heat exchanger discharge opening is connected to the first discharge opening or the first discharge openings, the second heat exchanger discharge opening is connected to the second discharge opening or the second discharge openings and the heat exchanger inert gas discharge opening is connected to the inert gas discharge opening or the inert gas discharge openings.

[0017] In one embodiment of the plate heat exchanger, the front plate is designed in the form of a heat exchanger plate according to the invention.

[0018] In one embodiment of the plate heat exchanger, the heat exchanger inert gas discharge opening is closed with a valve such that any excess pressure can be released by means of the valve.

[0019] In one embodiment of the plate heat exchanger, a plurality of first fluid spaces and a plurality of second fluid spaces are provided. A heat exchanger plate according to the invention is arranged between each of the first fluid spaces and each of the second fluid spaces. First seals separate the second supply opening and the second discharge opening of the respective heat exchanger plate from the first fluid spaces in the first fluid spaces. Second seals separate the first supply opening, the first discharge opening, and the inert gas discharge opening of the respective heat exchanger plate from the second fluid spaces in the second fluid spaces.

[0020] A water treatment system comprises an inlet for water, a first outlet for treated water, and a second outlet for wastewater, a first water vessel, an evaporator-condenser unit, a mist eliminator, and a compressor. The inlet is connected to the water vessel. The water vessel is connected to an evaporator inlet of an evaporator of the evaporator-condenser unit. An evaporator outlet of the evaporator of the evaporator-condenser unit is connected to the mist eliminator. The mist eliminator is connected to a condenser inlet of a condenser of the evaporator-condenser unit. A condenser outlet of the condenser of the evaporator-condenser unit is connected to the first outlet. The compressor is arranged between the mist eliminator and the condenser inlet. The compressor is configured to generate a negative pressure on the side of the mist eliminator.The evaporator-condenser unit comprises a plate heat exchanger according to the invention. The evaporator inlet is connected to the second supply opening. The evaporator outlet is connected to the second discharge opening. The condenser inlet is connected to the first supply opening. The condenser outlet is connected to the first discharge opening.

[0021] Embodiments of the invention are explained with reference to the following drawings. The schematic drawing shows: Fig. 1 a heat exchanger plate; Fig. 2 an exploded drawing of a plate heat exchanger; Fig. 3 an exploded drawing of a plate heat exchanger; Fig. 4 an exploded drawing of a plate heat exchanger; Fig. 5 a cross section of a plate heat exchanger; Fig. 6 a cross section of a plate heat exchanger; Fig. 7 a heat exchanger plate; Fig. 8 an exploded drawing of a plate heat exchanger; Fig. 9 a heat exchanger plate; Fig. 10 an exploded drawing of a plate heat exchanger; and Fig. 11 a water treatment plant.

[0022] Fig. 1 shows a heat exchanger plate 1 with a first supply opening 2, a second supply opening 3, a first discharge opening 4 and a second discharge opening 5, further comprising an inert gas discharge opening 6. The inert gas discharge opening 5 can be used to remove non-condensable components during operation of a heat exchanger.

[0023] The heat exchanger plate 1 is designed such that the first supply opening 2, the second supply opening 3, the first discharge opening 4, and the second discharge opening 5 are each arranged in different corner regions 9 of the heat exchanger plate 1. The heat exchanger plate 1 is rectangular. One of the aforementioned openings 2, 3, 4, 5 is arranged in each of the four corner regions 9. The inert gas discharge opening 6 is arranged closer to the first supply opening 2 and the second discharge opening 5 than to the second supply opening 3 and the first discharge opening 4. Depending on the flow direction of fluids flowing in a plate heat exchanger, the first supply opening 2, the second supply opening 3, the first discharge opening 4, and the second discharge opening 5 can each also be arranged in other corner regions 9, wherein each corner region 9 can have one of these openings 2, 3, 4, 5.

[0024] Fig. 2 shows an exploded view of a plate heat exchanger 10 with three heat exchanger plates 1, which, like the heat exchanger plate 1 of the Fig. 1 are designed, a front plate 11 and an end plate 12. The heat exchanger plates 1, the front plate 11 and the end plate 12 each have a circumferential seal 20 with which they can be sealed against a housing, not shown. The plate heat exchanger 10 further has two first fluid chambers 13 and two second fluid chambers 14, wherein each heat exchanger plate 1 is arranged between a first fluid chamber 13 and a second fluid chamber 14. The fluid chambers 13, 14 are therefore each formed between two heat exchanger plates 1 or front plate 11 and end plate 12 and each one heat exchanger plate 1 and the housing, not shown. The housing is indicated by dotted lines. First seals 21 in the first fluid chamber separate the second supply opening 3 and the second discharge opening 5 of the heat exchanger plate 1 from the first fluid chamber 13.Second seals 22 in the second fluid chamber 14 separate the first supply opening 2, the first discharge opening 4 and the inert gas discharge opening 6 of the heat exchanger plate 1 from the second fluid chamber 14.

[0025] The front plate 11, the heat exchanger plates 1, and the end plate 12 can be held together with clamping screws. This allows for easy expansion of the plate heat exchanger 10 by simply adding two additional heat exchanger plates 11 and thus a further first fluid chamber 13 and a further second fluid chamber 14. Of course, two heat exchanger plates 1 can also be omitted, thus eliminating a first fluid chamber 13 and a second fluid chamber 14.

[0026] The plate heat exchanger 10 further has a first heat exchanger supply opening 31 in the front plate 11, a second heat exchanger supply opening 32 in the end plate 12, a first heat exchanger discharge opening 33 in the front plate 11, a second heat exchanger discharge opening 34 in the end plate, and a heat exchanger inert gas discharge opening 35 in the front plate 11. The first heat exchanger supply opening 31 is connected to the first supply openings 2. The second heat exchanger supply opening 32 is connected to the second supply openings 3. The first heat exchanger discharge opening 33 is connected to the first discharge openings 4. The second heat exchanger discharge opening 34 is connected to the second discharge openings 5. The heat exchanger inert gas discharge opening 35 is connected to the inert gas discharge openings 6.Non-condensable components can be removed during operation of the plate heat exchanger 10 via the heat exchanger inert gas discharge opening 35. Because the first heat exchanger discharge opening 33 and the first heat exchanger discharge opening 33 are arranged in the front plate 11 and the second heat exchanger supply opening 32 and the second heat exchanger discharge opening 34 are arranged in the end plate 12, the plate heat exchanger 10 can be operated according to the countercurrent principle, in which heat can be effectively transferred from a first fluid with a first flow direction 15 to a second fluid with a second flow direction 16. The flow directions 15, 16 are represented by dashed lines.

[0027] Instead of clamping screws, the front plate 11, the heat exchanger plates 1, and the end plate 12 can also be held together in other ways. For example, the plate heat exchanger 10 can be soldered. In this design, the individual plates 1, 11, and 12 are soldered together, eliminating the need for clamping screws. Another design consists of laser-welded cassettes. Here, two heat exchanger plates 1 are welded together using a laser to form a gas-tight cassette. The plate pack is clamped together with clamping screws, allowing disassembly or expansion at any time. This design is particularly suitable for a critical medium (welded gap) and a service medium (sealed gap). Either the first seals 21 or the second seals 22 can therefore be omitted.

[0028] In all of the plate heat exchangers 10 mentioned, intensive heat transfer takes place, which can be further enhanced by turbulence in the flow. Turbulent flow is primarily achieved by a profile on the heat exchanger plates 1.

[0029] Fig. 3 shows an exploded view of a plate heat exchanger 10, which corresponds to the plate heat exchanger 10 of the Fig. 2 unless differences are described below. The front plate 11 is like the heat exchanger plate 1 of the Fig. 1 designed so that the second heat exchanger supply opening 32 and the second heat exchanger discharge opening 34 are also arranged in the front plate 11 and thus not in the end plate 12. This changes the second flow direction 16. Such a plate heat exchanger is even easier to expand because only the end plate 12 needs to be removed, two further heat exchanger plates 1 with circumferential seals 20, first seal 21 and second seal 22 inserted and then the end plate 12 needs to be reassembled. Since the openings 31, 32, 33, 34, 35 are all arranged in the front plate 11, nothing needs to be changed at the connections of the plate heat exchanger 10. First seals 21 are arranged between the end plate 12 and the adjacent heat exchanger plate 1 to prevent any connection between the first fluid spaces 13 and the second fluid spaces.Alternatively, the second supply opening 3 and the second discharge opening 5 could be omitted in this heat exchanger plate 1.

[0030] Fig. 4 shows an exploded view of a plate heat exchanger 10, which corresponds to the plate heat exchanger 10 of the Fig. 2 unless differences are described below. The first heat exchanger discharge opening 33 is located in the end plate 12 and not in the front plate 11. The second heat exchanger discharge opening 34 is located in the front plate 11 and not in the end plate 12. This changes the first flow direction 15 and the second flow direction 16.

[0031] If the plate heat exchangers 10 of the Fig. 2 bis 4 When used as an evaporator-condenser unit of a water treatment plant, it can be provided that water vapor is introduced into the first fluid spaces 13 via the first heat exchanger supply opening 31 and water is introduced into the second fluid spaces 14 via the second heat exchanger supply opening 32. The water vapor in the first fluid spaces 13 condenses due to the lower temperature of the water in the second fluid spaces 14, whereby condensation heat is transferred to the water in the second fluid spaces 14 and the water arranged in the second fluid spaces 14 is heated and optionally evaporated. The condensed water is discharged via the first heat exchanger discharge opening 33, while the heated water or, if applicable, already water vapor is discharged via the second heat exchanger discharge opening 34.Inert gases that also enter the first fluid spaces 13 via the first heat exchanger supply opening 31 are not condensed, but can be removed from the plate heat exchanger via the inert gas discharge openings 6 of the heat exchanger plates 1 and the heat exchanger inert gas discharge opening 35.

[0032] Fig. 5 shows a cross section through a plate heat exchanger 10, which as in the Figur 2 shown. Water condensing in the first fluid spaces 13 can fill the first fluid spaces 13 such that a maximum fill level lies below the inert gas discharge openings 6, so that non-condensable components can be guided through the inert gas discharge openings 6. The fill level can also be used to adjust the amount of heat transferred, since a different effective plate size of the heat exchanger plate 1 is available depending on the fill level.

[0033] A valve 25 is arranged at the heat exchanger inert gas discharge opening 35. The heat exchanger inert gas discharge opening 35 is closed by the valve 25 such that any excess pressure can be released by means of the valve 25. The valve 25 can, in particular, be a pressure relief valve, and it can be provided that the valve 25 releases any excess pressure generated in the first fluid chambers 13 by the non-condensable components.

[0034] Fig. 6 shows a cross section through a plate heat exchanger 10, which corresponds to the plate heat exchanger 10 of the Fig. 5 unless differences are described below. The valve 25 is replaced by a pump 26. A volume flow through the inert gas discharge openings 6 corresponds to a maximum of one hundredth of a volume flow supplied via the first supply opening 2, wherein the volume flow discharged via the inert gas discharge opening 6 is adjusted by means of the pump 26. Optionally, as in Fig. 6 shown, the supplied volume flow is supplied via the first heat exchanger supply opening 31 and the discharged volume flow is discharged via the heat exchanger inert gas discharge opening 35.

[0035] The valve 25 and the pump 26 can also be used together. The Fig. 5 and 6 The features explained can also be used in the plate heat exchangers 10 of the Fig. 3 und 4 be used.

[0036] Fig. 7 shows a heat exchanger plate 1, which corresponds to the heat exchanger plate 1 of the Fig. 1 unless differences are described below. The inert gas discharge opening 6 is designed as an elongated hole 7 in this embodiment. The first supply opening 2, the second supply opening 3, the first discharge opening 4 and the second discharge opening 5 are round and as shown in Fig. 1 shown. The elongated hole 7 can in particular be designed such that, at different filling levels, the elongated hole 7 extends to different depths into the liquid level, while nevertheless allowing the non-condensable components to be removed above the filling level.

[0037] Fig. 8 shows an exploded view of a plate heat exchanger 10, which is similar in basic design to the plate heat exchanger 10 of Fig. 2 corresponds, but with the heat exchanger plate 1 of the Fig. 7 Optionally, Fig. 8 It is shown that the front plate 11 can also have a slotted hole 7, which is connected to the heat exchanger inert gas discharge opening 35. A sight glass 36 is arranged here, with which the filling level of the plate heat exchanger can be checked. Alternatively, the front plate 11 can also be designed as described in connection with Fig. 2 The functioning of the plate heat exchanger 10 otherwise corresponds to that of the plate heat exchanger 10 of the Fig. 2 . The information related to the Figuren 3 bis 6 The adjustments explained can also be made for the plate heat exchanger 10 of the Fig. 8 be provided.

[0038] Fig. 9 shows a heat exchanger plate 1, which corresponds to the heat exchanger plate 1 of the Fig. 1 unless differences are described below. The inert gas discharge opening 6 and the first discharge opening 4 are designed as a common opening 8 in the heat exchanger plate 1. In this exemplary embodiment, the common opening is also designed as an elongated hole 7. This eliminates the need for an opening in the heat exchanger plate 1 and allows for a simpler structure, while retaining the advantages of the elongated hole 7.

[0039] Fig. 10 shows an exploded view of a plate heat exchanger 10, which is similar in basic design to the plate heat exchanger 10 of Fig. 2 corresponds, but with the heat exchanger plate 1 of the Fig. 9 The front panel 11 in this embodiment is as described in connection with Fig. 2 The operation of the plate heat exchanger 10 otherwise corresponds to that of the plate heat exchanger 10 of the Fig. 2 . The information related to the Figuren 3 bis 6 The adjustments explained can also be made for the plate heat exchanger 10 of the Fig. 10 Furthermore, the front panel 11 can also be provided as in connection with Fig. 8 explained.

[0040] Fig. 11 shows a water treatment system 100 with an inlet 101 for water, a first outlet 102 for treated water, and a second outlet 103 for wastewater, a water vessel 104, an evaporator-condenser unit 110, a droplet separator 105, and a compressor 120. The inlet 101 is connected to the water vessel 104. The water vessel 104 is connected to an evaporator inlet 112 of an evaporator 111 of the evaporator-condenser unit 110. An evaporator outlet 113 of the evaporator 111 of the evaporator-condenser unit 110 is connected to the droplet separator 105 arranged in the water vessel 104. The droplet separator 105 is connected to a condenser inlet 117 of a condenser 116 of the evaporator-condenser unit 110. A condenser outlet 118 of the condenser 116 of the evaporator-condenser unit 110 is connected to the first outlet 102. The compressor 120 is arranged between the droplet separator 105 and the condenser inlet 117.The compressor 120 is configured to generate a negative pressure on the side of the droplet separator 105. The evaporator-condenser unit 110 is designed as a plate heat exchanger 10 analogous to the embodiments described above, with the first fluid chamber 13 forming the condenser 116 and the second fluid chamber forming the evaporator 111. The first heat exchanger supply opening 31 corresponds to the condenser inlet 117, the second heat exchanger supply opening 32 corresponds to the evaporator inlet 112, the first heat exchanger discharge opening 33 corresponds to the condenser outlet 118, and the second heat exchanger discharge opening 34 corresponds to the evaporator outlet 113. In such a water treatment plant 100, the described plate heat exchanger 10 can be used well, since the non-condensable components or inert gases that reach the condenser 116 can be discharged via the heat exchanger inert gas discharge opening 35.For this purpose, the previously described pumps 26 or valves 25 can be used. Depending on the geometric requirements of the plate heat exchanger 10, the parameters associated with the . Fig. 2 bis 4 explained basic design variants of the plate heat exchanger 10. A vaporous volume flow leaves the plate heat exchanger 10 via the inert gas discharge openings 6. This can be done by means of a drain valve 25 or a pump 26 as shown in the Fig. 5 or 6 shown.

[0041] The droplet separator 105 is designed as a nozzle 106 and a mesh 107. If water is evaporated in the evaporator 111, any water present can be entrained as droplets. These droplets are retained by the mesh 107 and flow back down into the water vessel 104, while the water vapor can leave the droplet separator 105 upwards. Alternatively to the representation of the Fig. 11Other designs of the droplet separator 105, such as cyclone separators, are also conceivable.

Claims

1. Plate heat exchanger (10) having at least one heat exchanger plate (1), a front plate (11) and an end plate (12), wherein the heat exchanger plate (1) has a first supply opening (2), a second supply opening (3), a first discharge opening (4) and a second discharge opening (5) and an inert gas discharge opening (6), wherein the plate heat exchanger (10) also has at least one first fluid chamber (13) and at least one second fluid chamber (14), wherein each heat exchanger plate (1) is arranged between a first fluid chamber (13) and a second fluid chamber (14), wherein first seals (21) in the first fluid chamber (13) separate the second supply opening (3) and the second discharge opening (5) of the heat exchanger plate (1) from the first fluid chamber (13) and wherein second seals (22) in the second fluid chamber (14) separate the first supply opening (2), the first discharge opening (4) and the inert gas discharge opening (6) of the heat exchanger plate (1) from the second fluid chamber (14), characterized in that a volume flow via the inert gas discharge opening (6) corresponds to a maximum of one tenth of a volume flow supplied via the first supply opening (2), and in that the volume flow discharged via the inert gas discharge opening (6) is set by means of a pump (26).

2. Plate heat exchanger (10) according to Claim 1, wherein the inert gas discharge opening (6) comprises a slot (7), wherein the first supply opening (2), the second supply opening (3) and the second discharge opening (5) are of round design.

3. Plate heat exchanger (10) according to Claim 1 or 2, wherein the inert gas discharge opening (6) and the first discharge opening (4) are designed as a common opening (8) of the heat exchanger plate (1).

4. Plate heat exchanger (10) according to one of Claims 1 to 3, also having a first heat exchanger supply opening (31), a second heat exchanger supply opening (32), a first heat exchanger discharge opening (33), a second heat exchanger discharge opening (34) and a heat exchanger inert gas discharge opening (35), wherein the first heat exchanger supply opening (31) is connected to the first supply opening (2) or the first supply openings (2), the second heat exchanger supply opening (32) is connected to the second supply opening (3) or the second supply openings (3), the first heat exchanger discharge opening (33) is connected to the first discharge opening (4) or the first discharge openings (4), the second heat exchanger discharge opening (34) is connected to the second discharge opening (5) or the second discharge openings (5), and the heat exchanger inert gas discharge opening (35) is connected to the inert gas discharge opening (6) or the inert gas discharge openings (6).

5. Plate heat exchanger according to Claim 4, wherein the heat exchanger inert gas discharge opening (35) is closed with a valve (25) in such a way that any overpressure can be discharged by means of the valve (25).

6. Plate heat exchanger (10) according to one of Claims 1 to 5, wherein the front plate (11) is designed in the form of a heat exchanger plate (1) having a first supply opening (2), a second supply opening (3), a first discharge opening (4) and a second discharge opening (5) and an inert gas discharge opening (6).

7. Plate heat exchanger (10) according to one of Claims 1 to 6, wherein a plurality of first fluid chambers (13) and a plurality of second fluid chambers (14) are provided, wherein in each case a heat exchanger plate (1) according to Claims 1 to 3 is arranged between one of the first fluid chambers (13) and one of the second fluid chambers (14), and wherein first seals (21) in the first fluid chambers (13) separate the second supply opening (3) and the second discharge opening (5) of the heat exchanger plate (1) from the first fluid chambers (13) and wherein second seals (22) in the second fluid chambers (14) separate the first supply opening (2), the first discharge opening (4) and the inert gas discharge opening (6) of the heat exchanger plate (1) from the second fluid chambers (14).

8. Water treatment plant (100) having an inlet (101) for water, a first outlet (102) for treated water and a second outlet (103) for waste water, a water vessel (104), an evaporator-condenser unit (110), a droplet separator (105) and a compressor (120), wherein the inlet (101) is connected to the water vessel (104), wherein the water vessel (104) is connected to an evaporator inlet (112) of an evaporator (111) of the evaporator-condenser unit (110), wherein an evaporator outlet (113) of the evaporator (111) of the evaporator-condenser unit (110) is connected to the droplet separator (105), wherein the droplet separator (105) is connected to a condenser inlet (117) of a condenser (116) of the evaporator-condenser unit (110), wherein a condenser outlet (118) of the condenser (116) of the evaporator-condenser unit (110) is connected to the first outlet (102), wherein the compressor (120) is arranged between the droplet separator (105) and the condenser inlet (117), wherein the compressor (120) is configured to generate a negative pressure on the side of the droplet separator (105), wherein the evaporator-condenser unit (110) comprises a plate heat exchanger (10) according to one of Claims 1 to 7, wherein the evaporator inlet (112) is connected to the second supply opening (3), wherein the evaporator outlet (113) is connected to the second discharge opening (5), wherein the condenser inlet (117) is connected to the first supply opening (2), wherein the condenser outlet (118) is connected to the first discharge opening (4).