Sewage heat exchange system

Abstract

The invention discloses a sewage heat exchange system, relates to the technical field of sewage heat exchange, and aims to solve the problems of limited heat exchange area and low heat exchange efficiency. The sewage heat exchange system comprises a sewage treatment tank, a plurality of falling film heat exchangers, a condenser and a compressor. The falling-film heat exchangers are arranged in the sewage treatment tank in parallel, and refrigerant inlets and refrigerant steam outlets are formed in the upper ends of the falling-film heat exchangers; the falling film heat exchanger comprises two opposite heat exchange outer plates and at least one annular heat exchange plate, and the annular heat exchange plate is located between the two heat exchange outer plates. A heat exchange cavity communicated with the refrigerant inlet and the refrigerant steam outlet is formed between the inner wall of the heat exchange outer plate and the outer ring wall of the annular heat exchange plate; the inner wall of the heat exchange outer plate and the outer ring wall of the annular heat exchange plate are both used for making contact with a refrigerant and forming a liquid film. And the refrigerant inlets are communicated with the condenser. The refrigerant steam outlets are all communicated with the compressor, and the compressor is communicated with the condenser. The sewage heat exchange system is used for increasing the heat exchange area and improving the heat exchange efficiency.

Description

Technical Field

[0001] The invention relates to the technical field of sewage heat exchange, and in particular to a sewage heat exchange system. Background Art

[0002] During the sewage treatment process, the sewage carries a lot of heat. During the treatment of high-temperature sewage, the excess heat is directly discharged into the atmosphere, resulting in a large waste of heat energy. At present, for the waste heat recovery in the sewage cooling process, the hot water after precipitation is usually exchanged through a heat exchanger to fully utilize the heat.

[0003] The traditional sewage heat exchange system mainly places tubular or plate heat exchangers in sewage treatment tanks for direct heat exchange. However, due to the limited space in the sewage treatment tank, the heat exchange area of ​​the heat exchanger is limited, and the heat exchange efficiency is low. Summary of the invention

[0004] The object of the present invention is to provide a sewage heat exchange system, which is used to increase the heat exchange area of ​​the sewage heat exchange system and improve the heat exchange efficiency.

[0005] In order to achieve the above-mentioned purpose, the present invention provides a sewage heat exchange system, including a sewage treatment tank, a plurality of falling film heat exchangers, a condenser and a compressor. A plurality of falling film heat exchangers are arranged in parallel in the sewage treatment tank, and the upper end of the falling film heat exchanger has a refrigerant inlet and a refrigerant vapor outlet; the falling film heat exchanger includes two opposite heat exchange outer plates and at least one annular heat exchange plate, and the number of the annular heat exchange plates can be 1, 2, 3, 4, etc. The annular heat exchange plate is located between the two heat exchange outer plates; a heat exchange cavity connected to the refrigerant inlet and the refrigerant vapor outlet is formed between the inner wall of the heat exchange outer plate and the outer ring wall of the annular heat exchange plate; wherein the outer wall of the heat exchange outer plate and the inner ring wall of the annular heat exchange plate are both used to contact with sewage, and the inner ring of the annular heat exchange plate is used for the circulation of sewage; the inner wall of the heat exchange outer plate and the outer ring wall of the annular heat exchange plate are both used to contact with the refrigerant and form a liquid film. Each refrigerant inlet is connected to the condenser. Each refrigerant vapor outlet is connected to the compressor, and the compressor is connected to the condenser.

[0006] Compared with the prior art, the two relative outer heat exchange plates and at least one annular heat exchange plate of a falling film heat exchanger of a sewage heat exchange system provided by the present invention can contact and exchange heat with sewage. Compared with the single-plate heat exchange method in the prior art, the heat exchange area is increased, and the heat exchange efficiency is greatly improved by the liquid film heat absorption and evaporation method. In the present application, multiple falling film heat exchangers are arranged in parallel in the sewage treatment tank, which can further improve the heat exchange efficiency. Moreover, when some of the falling film heat exchangers need to be repaired or cleaned, the other falling film heat exchangers can still continue to work, ensuring the uninterrupted and continuous heat exchange of the sewage heat exchange system. In addition, the refrigerant circulates directly between the heat exchanger and the condenser in the sewage treatment tank through a compressor, eliminating the source side water pump, the source side heat exchanger and the intermediate pump in the prior art, reducing the energy consumption of the two water pumps and the heat loss of the source side heat exchanger.

[0007] In some possible embodiments, the heat exchange outer plate and / or the annular heat exchange plate are wavy. For example, the heat exchange outer plate is wavy. Alternatively, the annular heat exchange plate is wavy. Alternatively, both the heat exchange outer plate and the annular heat exchange plate are wavy.

[0008] In some possible embodiments, the falling film heat exchanger further includes a liquid separation main pipe and a plurality of liquid separation branch pipes connected to each other. The liquid separation main pipe is connected to the refrigerant inlet. The liquid separation branch pipes are used to distribute the refrigerant to the inner wall of the heat exchange outer plate and the outer ring wall of the annular heat exchange plate.

[0009] In some possible implementations, each liquid separation branch pipe is provided with a plurality of through holes, and the through holes face the inner wall of the heat exchange outer plate or the outer ring wall of the annular heat exchange plate.

[0010] In some possible implementations, the sewage heat exchange system further includes a first refrigerant input pipe and a second refrigerant input pipe, the first refrigerant input pipe and the second refrigerant input pipe are detachably connected, the second refrigerant input pipe is fixedly connected to the falling film heat exchanger, and the condenser is connected to the second refrigerant input pipe through the first refrigerant input pipe. The sewage heat exchange system further includes a first refrigerant output pipe and a second refrigerant output pipe, the first refrigerant output pipe and the second refrigerant output pipe are detachably connected, the second refrigerant output pipe is fixedly connected to the falling film heat exchanger, and the compressor is connected to the second refrigerant output pipe through the first refrigerant output pipe.

[0011] In some possible implementations, the sewage heat exchange system further includes a fixed bracket, which is disposed on the falling film heat exchanger, the fixed bracket is detachably connected to the falling film heat exchanger, and the fixed bracket is fixedly connected to the sewage treatment tank.

[0012] In some possible implementations, the sewage heat exchange system further includes a guide plate, which is fixedly disposed at one end of the annular heat exchange plate, and the sewage is gathered through the guide plate and flows through the inner ring of the annular heat exchange plate.

[0013] In some possible implementations, the sewage heat exchange system further includes a track, which is fixedly disposed in the sewage treatment tank, and the falling film heat exchanger is slidably connected to the track.

[0014] In some possible implementations, the sewage heat exchange system further includes at least two leveling mechanisms, which are disposed at the bottom of the falling film heat exchanger and are used to level the falling film heat exchanger.

[0015] In some possible implementations, the sewage heat exchange system further includes a tubular aerator, one end of which is disposed within the inner ring of the annular heat exchange plate. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0017] Figure 1 A schematic diagram of a sewage heat exchange system provided by an embodiment of the present invention;

[0018] Figure 2 A schematic diagram of a local structure of a sewage heat exchange system provided by an embodiment of the present invention;

[0019] Figure 3 A schematic diagram of the internal structure of a falling film heat exchanger provided in an embodiment of the present invention;

[0020] Figure 4 A schematic diagram of the internal structure of a falling film heat exchanger from another angle provided in an embodiment of the present invention;

[0021] Figure 5 A schematic structural diagram of a sewage heat exchange system provided by an embodiment of the present invention;

[0022] Figure 6 for Figure 5 The schematic diagram of the structure of the sewage heat exchange system shown in another angle;

[0023] Figure 7 for Figure 6 A partial structural schematic diagram of a sewage heat exchange system shown;

[0024] Figure 8 for Figure 5 A schematic diagram of the structure of the sewage heat exchange system during the removal of the falling film heat exchanger is shown;

[0025] Fig. 9 for Figure 5 Another structural schematic diagram of the sewage heat exchange system during the removal of the falling film heat exchanger is shown;

[0026] Fig.10A schematic diagram of the structure of a sewage heat exchange system provided in an embodiment of the present invention after a portion of the falling film heat exchanger is removed.

[0027] Reference numerals:

[0028] 1-wastewater treatment tank; 2-falling film heat exchanger; 21-refrigerant inlet; 22-refrigerant vapor outlet; 23-heat exchange outer plate; 24-annular heat exchange plate; 25-heat exchange chamber; 26-liquid separation main pipe; 27-liquid separation branch pipe; 3-condenser; 4-compressor; 5-first refrigerant input pipe; 51-main input pipe; 52-sub-input pipe; 6-second refrigerant input pipe; 7-first refrigerant output pipe; 71-main output pipe; 72-sub-output pipe; 8-second refrigerant output pipe; 9-fixed bracket; 10-drainage plate; 11-track; 12-leveling mechanism; 13-tubular aerator; 14-gas pipeline. DETAILED DESCRIPTION

[0029] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0030] It should be noted that when an element is referred to as being "fixed on" or "set on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0031] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined. The meaning of "several" is one or more, unless otherwise clearly and specifically defined.

[0032] In the description of the present invention, it is necessary to understand that the terms "upper", "lower", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0033] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the term "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0034] During the sewage treatment process, the sewage carries a large amount of heat. During the treatment of high-temperature sewage, the excess heat is directly discharged into the atmosphere, resulting in a large waste of heat energy. At present, for the waste heat recovery in the sewage cooling process, the hot water after precipitation is usually exchanged through a heat exchanger to make full use of the heat. The traditional sewage heat exchange system mainly places a tubular or plate heat exchange device in a sewage treatment tank for direct heat exchange. However, due to the limited space in the sewage treatment tank, the heat exchange area of ​​the heat exchanger is limited, and the heat exchange efficiency is low.

[0035] In order to solve the above problems, Figure 1 , Figure 2 and Figure 3 As shown, a sewage heat exchange system provided by an embodiment of the present invention includes a sewage treatment tank 1, a plurality of falling film heat exchangers 2, a condenser 3 and a compressor 4. A plurality of falling film heat exchangers 2 are arranged in parallel in the sewage treatment tank 1. The upper end of the falling film heat exchanger 2 has a refrigerant inlet 21 and a refrigerant vapor outlet 22; the falling film heat exchanger 2 includes two opposite heat exchange outer plates 23 and at least one annular heat exchange plate 24, and the annular heat exchange plate 24 is located between the two heat exchange outer plates 23; a heat exchange cavity 25 connected to the refrigerant inlet 21 and the refrigerant vapor outlet 22 is formed between the inner wall of the heat exchange outer plate 23 and the outer annular wall of the annular heat exchange plate 24; wherein the outer wall of the heat exchange outer plate 23 and the inner annular wall of the annular heat exchange plate 24 are both used for contact with sewage (such as Figure 1 The inner ring of the annular heat exchange plate 24 is used for the circulation of sewage; the inner wall of the heat exchange outer plate 23 and the outer ring wall of the annular heat exchange plate 24 are used to contact the refrigerant and form a liquid film. Each refrigerant inlet 21 is connected to the condenser 3. Each refrigerant vapor outlet 22 is connected to the compressor 4, and the compressor 4 is connected to the condenser 3.

[0036] In the specific implementation process of the sewage heat exchange system provided by the embodiment of the present invention, the falling film heat exchanger 2 is arranged in the sewage treatment tank 1, the sewage flows through the peripheral side of the falling film heat exchanger 2, and a part of the sewage flows into one end of the inner ring of the annular heat exchange plate 24, flows through the inner ring of the annular heat exchange plate 24, and finally flows out through the other end of the inner ring of the annular heat exchange plate 24. The refrigerant flows from the condenser 3 to the refrigerant inlet 21, and then flows to the inner wall of the heat exchange outer plate 23 and the outer ring wall of the annular heat exchange plate 24, and forms a liquid film on the inner wall of the heat exchange outer plate 23 and the outer ring wall of the annular heat exchange plate 24. The heat of the sewage flowing through the outer wall of the heat exchange outer plate 23 and the inner wall of the annular heat exchange plate 24 diffuses to the inner wall of the heat exchange outer plate 23 and the outer wall of the annular heat exchange plate 24, and evaporates the liquid film to form refrigerant vapor. The refrigerant vapor flows to the refrigerant vapor outlet 22 through the heat exchange cavity 25, and under the suction action of the compressor 4, flows to the compressor 4, and finally flows to the condenser 3 to complete the heat exchange.

[0037] Compared with the prior art, the falling film heat exchanger 2 of a sewage heat exchange system provided by the present invention includes two relative heat exchange outer plates 23 and at least one annular heat exchange plate 24, both of which can contact and exchange heat with sewage. Compared with the single-plate heat exchange method in the prior art, the heat exchange area is increased, and the heat exchange efficiency is greatly improved by the liquid film heat absorption and evaporation method. In the present application, multiple falling film heat exchangers 2 are arranged in the sewage treatment tank 1 in parallel, which can further improve the heat exchange efficiency. Moreover, when a part of the falling film heat exchangers 2 needs to be repaired or cleaned, the other falling film heat exchangers 2 can still continue to work, ensuring the uninterrupted and continuous heat exchange of the sewage heat exchange system. In addition, the refrigerant circulates directly between the heat exchanger and the condenser 3 in the sewage treatment tank 1 through the compressor 4, eliminating the source side water pump, the source side heat exchanger and the intermediate pump in the prior art, reducing the energy consumption of the two water pumps and the heat loss of the source side heat exchanger, and further improving the heat exchange efficiency. The refrigerant inlet 21 and the refrigerant vapor outlet 22 are both located at the upper end of the falling film heat exchanger 2 , which facilitates the communication between the refrigerant inlet 21 and the refrigerant vapor outlet 22 and the condenser 3 .

[0038] Exemplarily, the sewage treatment tank 1 may include any one of a secondary sedimentation tank, a coagulation sedimentation tank, a microfiltration tank, a clear water tank, etc. The falling film heat exchanger 2 may be arranged in any sewage treatment tank 1 for heat exchange.

[0039] In addition, the extending direction of the annular heat exchange plate 24 is consistent with the water flow direction in the sewage treatment tank 1, thereby ensuring that a large amount of sewage can flow through the inner ring of the annular heat exchange plate 24 for heat exchange.

[0040] The above implementation example Figure 1 As shown, an example is given in which the falling film heat exchanger 2 includes two annular heat exchange plates 24. In other embodiments of the present application, the number of the annular heat exchange plates 24 may also be other numbers, such as: 1, 3, 4, etc.

[0041] As a possible implementation method, the heat exchange outer plate 23 and / or the annular heat exchange plate 24 are wavy. For example, the heat exchange outer plate 23 is wavy. Alternatively, the annular heat exchange plate 24 is wavy. Alternatively, both the heat exchange outer plate 23 and the annular heat exchange plate 24 are wavy. Compared with the straight plate structure, the surface area of ​​the wavy structure is greatly increased, so as to increase the heat exchange area of ​​the heat exchange outer plate 23 or the annular heat exchange plate 24, thereby improving the heat exchange efficiency of the sewage heat exchange system.

[0042] For example, when the height of the outer heat exchange plate 23 of the falling film heat exchanger 2 is 2950 mm, the height of the annular heat exchange plate 24 is 2648 mm, the length of the falling film heat exchanger 2 is 2000 mm, and the number of the annular heat exchange plates 24 is 2, and the outer heat exchange plate 23 and the annular heat exchange plate 24 are in a straight plate structure, the total heat exchange area is about 49.2 m 2 When the heat exchange outer plate 23 and the annular heat exchange plate 24 have a wavy structure, the total heat exchange area is about 62.4m 2 That is, when the heat exchange outer plate 23 and the annular heat exchange plate 24 are wavy, the heat exchange area can be increased, thereby improving the heat exchange efficiency of the sewage heat exchange system.

[0043] As a possible way to achieve this, Figure 3 and Figure 4 As shown, the falling film heat exchanger 2 further includes a liquid separation main pipe 26 and a plurality of liquid separation branches 27 that are connected to each other. The liquid separation main pipe 26 is connected to the refrigerant inlet 21, and the liquid separation branches 27 are used to distribute the refrigerant to the inner wall of the heat exchange outer plate 23 and the outer ring wall of the annular heat exchange plate 24. The refrigerant enters the liquid separation main pipe 26 through the refrigerant inlet 21, and is distributed to the inner wall of the heat exchange outer plate 23 and the outer ring wall of the annular heat exchange plate 24 through the plurality of liquid separation branches 27. Then, a relatively uniform liquid film is formed on the inner wall of the heat exchange outer plate 23 and the outer ring wall of the annular heat exchange plate 24 to ensure the heat exchange effect.

[0044] In some embodiments, each liquid branch pipe 27 is provided with a plurality of through holes, and the through holes face the inner wall of the heat exchange outer plate 23 or the outer wall of the annular heat exchange plate 24. The refrigerant in the liquid branch pipe 27 is ejected onto the inner wall of the heat exchange outer plate 23 or the outer wall of the annular heat exchange plate 24 through the through holes, thereby forming a liquid film.

[0045] As a possible way to achieve this, Figure 5 , Figure 6 and Figure 7As shown, the sewage heat exchange system also includes a first refrigerant input pipe 5 and a second refrigerant input pipe 6, the first refrigerant input pipe 5 and the second refrigerant input pipe 6 are detachably connected, the second refrigerant input pipe 6 is fixedly connected to the falling film heat exchanger 2, and the condenser 3 is connected to the second refrigerant input pipe 6 through the first refrigerant input pipe 5. The sewage heat exchange system also includes a first refrigerant output pipe 7 and a second refrigerant output pipe 8, the first refrigerant output pipe 7 and the second refrigerant output pipe 8 are detachably connected, the second refrigerant output pipe 8 is fixedly connected to the falling film heat exchanger 2, and the compressor 4 is connected to the second refrigerant output pipe 8 through the first refrigerant output pipe 7. Exemplarily, the first refrigerant input pipe 5 and the second refrigerant input pipe 6 are flange-connected, and the first refrigerant output pipe 7 and the second refrigerant output pipe 8 are flange-connected.

[0046] The refrigerant can circulate through the condenser 3, the first refrigerant input pipe 5, the second refrigerant input pipe 6, the falling film heat exchanger 2, the second refrigerant output pipe 8, the first refrigerant output pipe 7, the compressor 4, and the condenser 3 to complete the heat exchange. In addition, the first refrigerant input pipe 5 and the second refrigerant input pipe 6 are detachably connected, and the first refrigerant output pipe 7 and the second refrigerant output pipe 8 are detachably connected. When the falling film heat exchanger 2 needs to be disassembled for inspection and cleaning, the second refrigerant input pipe 6 and the first refrigerant input pipe 5 can be disassembled, and the second refrigerant output pipe 8 and the first refrigerant output pipe 7 can be disassembled. The falling film heat exchanger 2, the second refrigerant input pipe 6, and the second refrigerant output pipe 8 are disassembled from the sewage heat exchange system together, and taken out from the sewage treatment tank 1 for inspection and cleaning.

[0047] Exemplarily, the first refrigerant input pipe 5 includes a main input pipe 51 and a plurality of sub-input pipes 52, each of which is connected to a second refrigerant input pipe 6. A first switch valve is provided on each sub-input pipe 52. The first refrigerant output pipe 7 includes a main output pipe 71 and a plurality of sub-output pipes 72, each of which is connected to a second refrigerant output pipe 8. A second switch valve is provided on each sub-input pipe 52. When it is necessary to disassemble one of the falling film heat exchangers 2, the first switch valve on the sub-input pipe 52 corresponding to the falling film heat exchanger 2 can be closed, and the second switch valve on the sub-output pipe 72 corresponding to the falling film heat exchanger 2 can be closed to ensure the normal operation of other falling film heat exchangers 2.

[0048] In some possible implementations, the sewage heat exchange system further includes a fixed bracket 9, which is disposed on the falling film heat exchanger 2, and the fixed bracket 9 is detachably connected to the falling film heat exchanger 2, and the fixed bracket 9 is fixedly connected to the sewage treatment tank 1. The falling film heat exchanger 2 is fixed by the fixed bracket 9 to prevent the falling film heat exchanger 2 from tilting under the action of the water flow, so that the liquid film is uneven and the heat exchange effect is affected.

[0049] In some embodiments, the sewage heat exchange system further includes a guide plate 10, which is fixedly disposed at one end of the annular heat exchange plate 24. The sewage is gathered through the guide plate 10 and flows through the inner ring of the annular heat exchange plate 24. The guide plate 10 can guide the sewage to the inner ring of the annular heat exchange plate 24, thereby increasing the sewage flow rate in the inner ring of the annular heat exchange plate 24 and increasing the convective heat exchange efficiency.

[0050] As a possible implementation method, the sewage heat exchange system further includes a track 11, which is fixedly arranged in the sewage treatment tank 1, and the falling film heat exchanger 2 is slidably connected to the track 11. On the one hand, the falling film heat exchanger 2 can be pulled away from the first refrigerant input pipe 5 and the first refrigerant output pipe 7 through the track 11, and then a part of the falling film heat exchanger 2 can be removed separately. On the other hand, the falling film heat exchanger 2 can also slide along the track 11, thereby changing the heat exchange position of the falling film heat exchanger 2, so as to perform heat exchange work on different areas of the sewage treatment tank 1.

[0051] When a part of the falling film heat exchanger 2 needs to be disassembled for maintenance and cleaning, for example, Figure 8 As shown, the corresponding second refrigerant input pipe 6 and the first refrigerant input pipe 5 are detached, and the corresponding second refrigerant output pipe 8 and the first refrigerant output pipe 7 are detached. A portion of the falling film heat exchanger 2, the second refrigerant input pipe 6, and the second refrigerant output pipe 8 are pulled out along the track 11. Then, as shown in FIG. Fig. 9 As shown, a portion of the membrane heat exchanger, the second refrigerant input pipe 6, and the second refrigerant output pipe 8 are lifted out of the sewage treatment tank 1, and then inspected and cleaned.

[0052] In some embodiments, the sewage heat exchange system also includes a motor, which drives the falling film heat exchanger 2, the first refrigerant input pipe 5, the second refrigerant input pipe 6, the first refrigerant output pipe 7 and the second refrigerant output pipe 8 to slide back and forth on the track 11, thereby continuously changing the heat exchange position, further improving the heat exchange efficiency of different areas of the sewage treatment tank 1.

[0053] As a possible way to achieve this, Figure 5 As shown, the sewage heat exchange system also includes at least two leveling mechanisms 12, which are arranged at the bottom of the falling film heat exchanger 2 and are used to level the falling film heat exchanger 2. Such an arrangement can ensure the horizontal placement of the falling film heat exchanger 2, thereby ensuring the uniformity of the liquid film formed on the heat exchange outer plate 23 and the annular heat exchange plate 24, and improving the heat exchange effect.

[0054] Exemplarily, the leveling mechanism 12 may include a leveling knob and a level gauge, and the falling film heat exchanger 2 is leveled by the leveling knob, and the horizontal degree of the falling film heat exchanger 2 is displayed by the level gauge.

[0055] In some possible implementations, such as Figure 5 and Fig.10 As shown, the sewage heat exchange system further includes a tubular aerator 13, one end of which is disposed in the inner ring of the annular heat exchange plate 24. Air is transported to the tubular aerator 13 through the air pipeline 14 by a blower or other equipment, and is dispersed and escaped in the form of bubbles, thereby impacting sediments, algae and other materials attached to the inner ring wall of the annular heat exchange plate 24, thereby cleaning the inner ring wall of the annular heat exchange plate 24.

[0056] In the description of the above embodiments, specific features, structures, materials or characteristics may be combined in a suitable manner in any one or more embodiments or examples.

[0057] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A sewage heat exchange system, characterized in that: include: sewage treatment tanks; A plurality of falling film heat exchangers, the plurality of falling film heat exchangers are arranged in parallel in the sewage treatment tank, the upper end of the falling film heat exchanger has a refrigerant inlet and a refrigerant vapor outlet; the falling film heat exchanger comprises two opposite heat exchange outer plates and at least one annular heat exchange plate, the annular heat exchange plate is located between the two heat exchange outer plates; a heat exchange cavity connected to the refrigerant inlet and the refrigerant vapor outlet is formed between the inner wall of the heat exchange outer plate and the outer ring wall of the annular heat exchange plate; The outer wall of the heat exchange outer plate and the inner ring wall of the annular heat exchange plate are both used to contact with sewage, and the inner ring of the annular heat exchange plate is used for the circulation of sewage; the inner wall of the heat exchange outer plate and the outer ring wall of the annular heat exchange plate are both used to contact with refrigerant and form a liquid film; A condenser, wherein the refrigerant inlet is in communication with the condenser; A compressor, the refrigerant vapor outlet is connected to the compressor, and the compressor is connected to the condenser.

2. The sewage heat exchange system according to claim 1, characterized in that: The heat exchange outer plate and / or the annular heat exchange plate are / is wavy in shape.

3. The sewage heat exchange system according to claim 1 or 2, characterized in that: The falling film heat exchanger also includes a connected liquid separation main pipe and a plurality of liquid separation branch pipes, wherein the liquid separation main pipe is connected to the refrigerant inlet, and the liquid separation branch pipes are used to distribute the refrigerant to the inner wall of the heat exchange outer plate and the outer ring wall of the annular heat exchange plate.

4. The sewage heat exchange system according to claim 3, characterized in that: Each of the liquid separation branches is provided with a plurality of through holes, and the through holes face the inner wall of the heat exchange outer plate or the outer ring wall of the annular heat exchange plate.

5. The sewage heat exchange system according to claim 1 or 2, characterized in that: The sewage heat exchange system further includes a first refrigerant input pipe and a second refrigerant input pipe, the first refrigerant input pipe and the second refrigerant input pipe are detachably connected, the second refrigerant input pipe is fixedly connected to the falling film heat exchanger, and the condenser is connected to the second refrigerant input pipe through the first refrigerant input pipe; The sewage heat exchange system also includes a first refrigerant output pipe and a second refrigerant output pipe, the first refrigerant output pipe and the second refrigerant output pipe are detachably connected, the second refrigerant output pipe is fixedly connected to the falling film heat exchanger, and the compressor is connected to the second refrigerant output pipe through the first refrigerant output pipe.

6. The sewage heat exchange system according to claim 4, characterized in that: The sewage heat exchange system also includes: A fixed bracket is arranged on the falling film heat exchanger, the fixed bracket is detachably connected to the falling film heat exchanger, and the fixed bracket is fixedly connected to the sewage treatment tank.

7. The sewage heat exchange system according to claim 1, characterized in that: The sewage heat exchange system also includes: A guide plate is fixedly arranged at one end of the annular heat exchange plate, and the sewage is gathered through the guide plate and flows through the inner ring of the annular heat exchange plate.

8. The sewage heat exchange system according to claim 1, characterized in that: The sewage heat exchange system also includes: A track is fixedly arranged in the sewage treatment tank, and the falling film heat exchanger is slidably connected to the track.

9. The sewage heat exchange system according to claim 1, characterized in that: The sewage heat exchange system also includes: At least two leveling mechanisms are arranged at the bottom of the falling film heat exchanger and are used to level the falling film heat exchanger.

10. The sewage heat exchange system according to claim 1, characterized in that: The sewage heat exchange system also includes: A tubular aerator, one end of which is arranged in the inner ring of the annular heat exchange plate.

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