A polymer film evaporation concentration system

Abstract

The embodiment of the present invention discloses a polymer film evaporation and concentration system, wherein a raw liquid pool is sequentially connected to raw liquid pipelines of a first plate preheater and a second plate preheater through a feed pump, the liquid outlet of the raw liquid pipeline of the second plate preheater is connected to a filter, the filter is connected to a film heat exchanger through a film evaporation circulation pump, and the liquid outlet of the film heat exchanger is connected to the filter. During the evaporation of the solution, the temperature of the solution is raised in advance through the effect of secondary preheating, so that during the evaporation process, the thermal energy utilization rate can be more effectively improved, and evaporation is efficient. In addition, a single-line closed-loop evaporation form is adopted, and a repeated evaporation process can be realized according to the concentration of the solution, thereby improving the evaporation efficiency.

Description

Technical Field

[0001] The embodiments of the present invention relate to the technical field of evaporation and concentration, and in particular to a polymer film evaporation and concentration system. Background Art

[0002] Evaporation concentration technology uses the principle of thermal interaction to increase the concentration of the solution, thereby achieving the purpose of crystallizing the solution. It has the advantages of large processing volume and high efficiency. It is mainly used in chemical and environmental wastewater treatment and seawater desalination. The existing concentration technology is mainly based on MVR evaporator.

[0003] The evaporation process is a process of heat exchange between steam and cold material. The steam lowers its temperature and condenses into water, while the cold material increases its temperature and vaporizes, thereby increasing the solute concentration. Traditional evaporators mostly use high-temperature heat sources. The MVR evaporator uses the steam evaporated from itself, which is returned to the system for heating after the compressor increases its temperature by 5-20℃. Therefore, the heat source temperature of the MVR evaporator is much lower than that of the traditional evaporator. Because traditional evaporators use high-temperature heat sources, only metal materials or graphite materials can be considered. The MVR evaporator uses a relatively low-temperature heat source. In this temperature range, polymer products can meet the use requirements, so it is completely feasible to use polymer materials as raw materials for heat exchangers.

[0004] Traditional evaporators are often made of metal materials, such as carbon steel, 304, 316L, 2205 titanium, etc. Non-metallic materials such as graphite are often used. These materials all have the problems of heavy equipment, high cost, and easy corrosion.

[0005] Compared with metal materials, polymer materials have the following advantages:

[0006] 1. Light weight and less material consumption per unit.

[0007] 2. High surface finish, not easy to scale

[0008] 3. The processing and manufacturing process is simple and easy to fully automate.

[0009] 4. Easy modular design reduces on-site installation and welding workload, and quality is guaranteed. Summary of the invention

[0010] To this end, an embodiment of the present invention provides a polymer film evaporation and concentration system to solve the problems in the prior art such as large floor space, low thermal energy utilization rate and high evaporator cost.

[0011] In order to achieve the above object, the embodiments of the present invention provide the following technical solutions:

[0012] In a first aspect of the embodiments of the present invention, a polymer thin film evaporation concentration system is provided, comprising:

[0013] Stock liquid pool: the stock liquid pool is sequentially connected to the stock liquid pipelines of the first plate preheater and the second plate preheater through a feed pump, the liquid outlet of the stock liquid pipeline of the second plate preheater is connected to a filter, the filter is connected to a film heat exchanger through a film evaporation circulation pump, and the liquid outlet of the film heat exchanger is connected to the filter;

[0014] Compressor: the compressed gas outlet of the compressor is connected to the inlet of the heat exchange structure of the membrane heat exchanger, the exhaust channel of the heat exchange structure is connected to the inlet of the compressor, the liquid discharge channel of the heat exchange structure is connected to the heating pipeline of the second plate preheater, the liquid outlet end of the heating pipeline of the second plate preheater is connected to the distilled water tank, the distilled water tank is connected to the heating pipeline of the first plate preheater through a condensate pump, and the outlet of the heating pipeline of the first plate preheater is connected to the liquid storage tank;

[0015] The liquid outlet end of the thin film evaporation circulation pump is also connected to the concentrated liquid pool.

[0016] Furthermore, the feed pipeline of the feed pump is also connected to the raw liquid pool, and a double feeding channel is arranged on the pipeline between the feed pump and the first plate preheater, and the feed pipeline connecting the feed pump to the raw liquid pool is located at the front end of the double feeding channel.

[0017] Furthermore, the liquid discharge channel of the compressor is connected to a liquid accumulation tank, and the liquid accumulation tank is connected to the distilled water tank via a liquid accumulation pump.

[0018] Furthermore, the film heat exchanger is also provided with a straight discharge port, and the straight discharge port is connected to the liquid accumulation tank.

[0019] Furthermore, the membrane heat exchanger includes an outer shell, a heat exchange structure is arranged inside the outer shell, a raw liquid inlet, a steam inlet and a non-condensable gas outlet connected to the heat exchange structure are arranged on the outer shell, the raw liquid inlet is connected to a material diffusion device arranged inside the outer shell, a raw liquid circulation outlet is arranged at the bottom of the outer shell, and a raw liquid steam outlet is arranged at the top of the outer shell.

[0020] Furthermore, the heat exchange structure includes a plurality of thin film heat exchange plates arranged in parallel, and the heat exchange structure includes an air inlet corresponding to the steam inlet, and two air outlets corresponding to the non-condensable gas outlets.

[0021] Furthermore, the thin film heat exchanger is one of an elliptical, gourd-shaped or S-shaped structure, and the longitudinal cross-sections at the upper and lower ends are arc-shaped structures. The thin film heat exchanger is an integrally molded structure made of polymer material, and the material is not limited to one or more combinations of PP, PE, PTFE, FEP, PEEK, and its thickness is 0.05-1mm.

[0022] Furthermore, the material diffusion device includes a plurality of evenly distributed liquid distribution pipes, a nozzle is provided at the end of the liquid distribution pipe, the nozzle includes a connecting part, a spray barrel is provided on the bottom side of the connecting part, and a plurality of evenly distributed spray holes are provided on the top circumference of the spray barrel.

[0023] Furthermore, a partition piece is provided inside the spray barrel, which is in close contact with the inside of the spray barrel and can seal the spray hole, and a supporting spring is provided on the bottom side of the partition piece.

[0024] Furthermore, the spray holes are arranged to be tilted downward from the inside of the spray barrel to the outside thereof, and the vertical center lines of the spray barrel form an angle of 45°.

[0025] According to the implementation mode of the present invention, this solution has the following advantages:

[0026] 1. In the technical solution of the present invention, the stock liquid pool is sequentially connected to the stock liquid pipelines of the first plate preheater and the second plate preheater through a feed pump, the liquid outlet of the stock liquid pipeline of the second plate preheater is connected to the filter, the filter is connected to the film heat exchanger through a film evaporation circulation pump, and the liquid outlet of the film heat exchanger is connected to the filter. During the evaporation of the solution, the temperature of the solution is raised in advance through the effect of secondary preheating, so that during the evaporation process, the thermal energy utilization rate can be more effectively improved, and the evaporation is efficient. In addition, the single-line closed-loop evaporation form is adopted, and the evaporation process can be repeated according to the concentration of the solution, thereby improving the evaporation efficiency;

[0027] 2. In the technical solution of the present invention, the compressed gas outlet of the compressor is connected to the inlet of the heat exchange structure of the membrane heat exchanger, the exhaust channel of the heat exchange structure is connected to the inlet of the compressor, the liquid discharge channel of the heat exchange structure is connected to the heating pipeline of the second plate preheater, the liquid outlet of the heating pipeline of the second plate preheater is connected to the distilled water tank, the distilled water tank is connected to the heating pipeline of the first plate preheater through a condensate pump, and the outlet of the heating pipeline of the first plate preheater is connected to the liquid storage tank, the heat required for evaporation is increased by compressed gas, and enters the evaporation system, and can be repeatedly compressed and utilized, and at the same time, a secondary gas-liquid mixture is formed and enters the preheating process to achieve the maximum utilization rate of the thermal energy of steam at different temperatures;

[0028] 3. The heat exchanger of the present invention has a heat exchange structure in the shell, a raw liquid inlet, a steam inlet and a non-condensable gas outlet connected to the heat exchange structure, the raw liquid inlet is connected to the material diffusion device arranged inside the shell, and a raw liquid circulation outlet is provided at the bottom of the shell. The material is concentrated and separated by contacting the material with the heat exchange device. The equipment has a simple structure, a reasonable layout, few connections between structures, and is easy to maintain.

[0029] 4. The heat exchange device in this scheme is made of polymer materials. Its oval structure is integrally formed with a smooth outer surface. Its heat transfer surface is difficult to scale, which greatly reduces the number of equipment maintenance times, ensures a relatively stable heat transfer coefficient and long-term production operation. At the same time, it has better corrosion resistance and thermal conductivity, longer service life, and reduced maintenance costs;

[0030] 5. In the material diffusion device of the present scheme, a partition piece is provided inside the nozzle structure, which is in close contact with the inside of the nozzle barrel and can seal the nozzle hole. A supporting spring is provided on the bottom side of the partition piece, which automatically sprays the material on the heat exchange device under working pressure, thereby improving the crystallization efficiency. At the same time, the nozzle can be automatically closed in a pressure-free state, thereby forming a one-way conveying structure, thereby preventing the steam formed after the evaporation of the material from being discharged from the fixed outlet instead of flowing back to the side of the material, thereby avoiding the accumulation of gas in the material pipeline and causing uneven material distribution during the next operation;

[0031] 6. Compared with the traditional heat exchange mechanism, the thin film heat exchanger in the present invention has the following characteristics:

[0032] Excellent corrosion resistance: Since the material of the heat exchanger is a chemically inert material, it can work in almost all media except elemental fluorine at high temperature, molten alkali metals, chlorine trifluoride, uranium hexafluoride, and perfluorokerosene. Such as: concentrated hydrochloric acid, hydrofluoric acid, sulfuric acid, nitric acid, phosphoric acid, acetic acid, oxalic acid, caustic soda, sodium hypochlorite, naphthalene, benzene, xylene, acetone, aqua regia, chlorine, toluene, various organic solvents, etc.

[0033] Good anti-scaling performance: Its elliptical structure, surface smoothness, flexibility and high expansion coefficient make it difficult for the heat transfer surface to scale, greatly reducing the number of equipment maintenance times, ensuring a relatively stable heat transfer coefficient and long-term production operation;

[0034] Long life and low overall cost: Since it does not contain photosensitive genes, it has excellent resistance to atmospheric aging. Its service life in highly corrosive media is 20 to 30 times that of stainless steel. In addition, it is free of losses caused by maintenance and accidental shutdowns, so its overall cost is definitely lower than other heat exchangers;

[0035] Good heat transfer performance: Since the heat exchanger uses thin-walled tubes with a wall thickness of only 0.5mm, 0.75mm, and 1mm, it overcomes the disadvantage of low thermal conductivity of polytetrafluoroethylene materials, making its total heat transfer coefficient reach 150-300 (W / m²·K);

[0036] Small resistance: Since F4 has a very small friction coefficient, low roughness and excellent lubrication performance, the resistance of the fluid in the tube bundle is smaller than that of a metal tube. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the implementation methods of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for the implementation methods or the description of the prior art. Obviously, the drawings in the following description are only exemplary, and for ordinary technicians in this field, other implementation drawings can be derived from the provided drawings without creative work.

[0038] The structures, proportions, sizes, etc. illustrated in this specification are only used to match the contents disclosed in the specification so as to facilitate understanding and reading by persons familiar with the technology. They are not used to limit the conditions under which the present invention can be implemented, and therefore have no substantial technical significance. Any structural modification, change in proportion or adjustment of size shall still fall within the scope of the technical contents disclosed in the present invention without affecting the effects and purposes that can be achieved by the present invention.

[0039] Figure 1 A system structure diagram of a polymer thin film evaporation concentration system provided by an embodiment of the present invention;

[0040] Figure 2 A schematic diagram of the internal structure of a thin film heat exchanger in a polymer thin film evaporation and concentration system provided by an embodiment of the present invention;

[0041] Figure 3 A schematic structural diagram of a heat exchange device in a polymer film evaporation concentration system provided by an embodiment of the present invention;

[0042] Figure 4 A schematic cross-sectional structure diagram of a nozzle in a polymer thin film evaporation and concentration system provided by an embodiment of the present invention.

[0043] In the figure:

[0044] Stock solution pool;

[0045] Feed pump;

[0046] First plate preheater;

[0047] Second plate preheater;

[0048] Filters;

[0049] Thin film evaporation circulation pump;

[0050] Membrane heat exchanger; 71, shell; 72, raw liquid inlet; 73, steam inlet; 74, non-condensable gas outlet; 75, raw liquid circulation outlet; 76, membrane heat exchanger; 77, raw liquid steam outlet;

[0051] Dispensing tube;

[0052] Nozzle; 91, connecting part; 92, nozzle; 93, spray hole; 94, partition; 95, support spring;

[0053] 10. Compressor; 11. Distilled water tank; 12. Condensate pump; 13. Liquid storage tank; 14. Concentrated liquid tank; 15. Liquid accumulation tank; 16. Liquid accumulation pump. DETAILED DESCRIPTION

[0054] The following is a description of the implementation of the present invention by specific embodiments. People familiar with the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0055] The terms such as "upper", "lower", "left", "right", "middle", etc. cited in this specification are only for the convenience of description and are not intended to limit the scope of the present invention. Changes or adjustments to their relative relationships should be regarded as within the scope of the present invention without substantially changing the technical content.

[0056] like Figure 1 As shown, it shows a polymer thin film evaporation concentration system provided by an embodiment of the present invention, comprising

[0057] Stock liquid pool 1: the stock liquid pool 1 is sequentially connected to the stock liquid pipelines of the first plate preheater 3 and the second plate preheater 4 through the feed pump 2, the liquid outlet of the stock liquid pipeline of the second plate preheater 4 is connected to the filter 5, the filter 5 is connected to the film heat exchanger 7 through the film evaporation circulation pump 6, and the liquid outlet of the film heat exchanger 7 is connected to the filter 5;

[0058] During the evaporation process of the solution, the temperature of the solution is raised in advance through the effect of secondary preheating, so that the thermal energy utilization rate can be more effectively improved during the evaporation process, and evaporation can be efficient. In addition, the single-line closed-loop evaporation form is adopted, which can realize repeated evaporation process according to the concentration of the solution and improve the evaporation efficiency.

[0059] Compressor 10: the compressed gas outlet of the compressor 10 is connected to the inlet of the heat exchange structure of the membrane heat exchanger 7, the exhaust channel of the heat exchange structure is connected to the inlet of the compressor 10, the liquid discharge channel of the heat exchange structure is connected to the heating pipeline of the second plate preheater 4, the liquid outlet end of the heating pipeline of the second plate preheater 4 is connected to the distilled water tank 11, the distilled water tank 11 is connected to the heating pipeline of the first plate preheater 3 through the condensate pump 12, and the outlet of the heating pipeline of the first plate preheater 3 is connected to the liquid storage tank 13;

[0060] A gas-liquid separator is provided at the liquid outlet of the heating pipeline of the second plate preheater 4, the liquid flows into the distilled water tank 11, and the gas is collected and utilized as exhaust gas. A proportional regulating valve is provided on the recovery pipeline, which can directly flow back to the compressor 10.

[0061] The compressor 10 is used to compress the gas to increase the heat required for evaporation, enter the evaporation system, and can be repeatedly compressed and utilized. At the same time, a secondary gas-liquid mixture is formed and enters the preheating process to achieve the maximum utilization rate of the thermal energy of steam at different temperatures. A circulating cooling water structure can be set on the compressor 10 to ensure the normal operating temperature range of the compressor 10 and ensure the normal operation of the compressor 10.

[0062] The liquid outlet of the thin film evaporation circulation pump is also connected to the concentrated liquid pool 14. A solution concentration sensor is arranged on the outlet pipeline of the thin film evaporation circulation pump. By detecting the solution concentration, the valve body leading to the thin film heat exchanger 7 or the concentrated liquid pool 14 can be selectively opened.

[0063] In this system, the liquid outlets of the feed pump 2, the thin film evaporation circulation pump 6, the condensate pump 12 and the effluent pump 16 are all provided with pressure gauges, wherein the pressure range of the feed pump 2 and the condensate pump 12 is 0-0.4MP, and the pressure range of the thin film evaporation circulation pump 6 and the effluent pump 16 is -0.1-0.3MP;

[0064] Liquid level sensors are provided in the original liquid pool 1, the liquid storage pool 13 and the concentrated liquid pool 14, which can monitor the volume of the solution in the pool in real time to ensure the normal operation of the system;

[0065] The liquid storage tank 15 is directly connected to the distilled water tank 11. A liquid high level interlocking sensor and a liquid low level interlocking sensor are arranged on the liquid storage tank 15. When the liquid level in the liquid storage tank 15 is relatively high, a liquid high level interlocking reaction occurs, i.e. the valve is opened directly to transport liquid to the distilled water tank 11 without using the liquid storage pump 16. The double transport process formed thereby avoids the pressure on the liquid storage tank 15 caused by the inability to transport liquid in time after a single pipeline fails, while ensuring the normal operation of the system.

[0066] A flow transmitter is provided on the pipeline between the raw liquid pump and the first plate preheater 3, and the flow transmitter is connected to the feed pump 2, which realizes real-time monitoring of the raw liquid flow and flow control of the feed pump 2. The flow transmitter provided at the liquid outlet of the membrane heat exchanger 7 is also connected to the feed pump 2; correspondingly, the flow transmitter provided between the first plate preheater 3 and the liquid storage tank 13 and the industry WeChat signal transmitter provided on the distilled water tank 11 are both connected to the condensate pump 12;

[0067] Temperature transmitters are provided on the pipeline connecting the second plate heat exchanger to the filter 5, the discharge port of the membrane heat exchanger 7 and the compressed gas output end of the compressor 10, which can detect the temperature changes of the corresponding nodes in real time.

[0068] In a further embodiment, the feeding pipeline of the feed pump 2 is also connected to the raw liquid pool 1, and a double feeding channel is arranged on the pipeline between the feed pump 2 and the first plate preheater 3. The feeding pipeline connecting the feed pump 2 to the raw liquid pool 1 is located at the front end of the double feeding channel. The double feeding channel can ensure the stability of the feeding process, and one of them is a spare channel node.

[0069] Among them, the discharge channel of the compressor 10 is connected to the liquid storage tank 15, and the liquid storage tank 15 is connected to the distilled water tank 11 through the liquid storage pump 16. The accumulated liquid formed in the compressor 10 directly flows into the liquid storage tank 15 and forms a preheating medium through circulation, ensuring full utilization of the heat in the system.

[0070] In another embodiment, the membrane heat exchanger 7 is further provided with a straight discharge port, which is connected to the liquid storage tank 15. The straight discharge port is arranged at the position of the non-condensable gas outlet 74. If there is steam condensation, it can be collected and refluxed for utilization.

[0071] like Figure 2 , Figure 3 As shown, the membrane heat exchanger 7 includes an outer shell 71, in which a heat exchange structure is arranged, a raw liquid inlet 72, a steam inlet 73 connected to the heat exchange structure, and a non-condensable gas outlet 74 are arranged on the outer shell 71, the raw liquid inlet 72 is connected to a material diffusion device arranged inside the outer shell 71, a raw liquid circulation outlet 75 is arranged at the bottom of the outer shell 71, and a raw liquid steam outlet 77 is arranged at the top of the outer shell 71, and the raw liquid steam outlet 77 is connected to the compressor 10.

[0072] By bringing the material into contact with the heat exchange device, the high-temperature medium passes through the interior of the heat exchange device 6, thereby concentrating and separating the material. The equipment has a simple structure, a reasonable layout, few connections between structures, and is easy to maintain.

[0073] The heat exchange structure includes a plurality of thin film heat exchange plates 76 arranged in parallel, and the heat exchange structure includes an air inlet corresponding to the steam inlet 73 and two air outlets corresponding to the non-condensable gas outlets 74 .

[0074] In a specific embodiment, the thin film heat exchanger 76 is an elliptical, gourd-shaped, S-shaped or other shaped structure, and its longitudinal cross-sections at the upper and lower ends are arc-shaped structures. The thin film heat exchanger 76 is an integrally molded structure made of a polymer material, such as PP, PE, PTFE, FEP, PEEK or other materials, but is not limited to one or more combinations of PP, PE, PTFE, FEP, PEEK, and its thickness is 0.1 mm, 0.5 mm, 0.75 mm, 1 mm. Its elliptical structure has a smooth outer surface, and its heat transfer surface is difficult to scale, which greatly reduces the number of equipment maintenance times, ensures a relatively stable heat transfer coefficient and long-term production operation, and at the same time, it has better corrosion resistance and thermal conductivity, a longer service life, and reduced maintenance costs.

[0075] like Figure 4 As shown, the material diffusion device includes a plurality of evenly distributed liquid distribution pipes 8, a nozzle 9 is provided at the end of the liquid distribution pipe 8, the nozzle 9 includes a connecting portion 91, a spray barrel 92 is provided on the bottom side of the connecting portion 91, and a plurality of evenly distributed spray holes 93 are provided on the top circumference of the spray barrel 92.

[0076] The interior of the spray barrel 92 is provided with a partition member 94 which is in close contact with the interior of the spray barrel 92 and can seal the spray hole 93 , and a supporting spring 95 is provided on the bottom side of the partition member 94 .

[0077] In the specific structure, the spray hole 93 is arranged to be tilted downward from the inside of the spray tube 92 to the outside thereof, and the vertical center line of the spray tube 92 forms an angle of 45°.

[0078] When the evaporation concentration system of the present invention is first started, the high-temperature gas needs to be compressed by the compressor 10 and passed into the heat exchanger plate of the membrane heat exchanger 7. Part of the steam flows into the second plate preheater 4. At the same time, the raw liquid pump is turned on. The raw liquid is preheated when flowing through the second plate preheater 4, and then circulated to the filter 5. The filter 5 passes the alkali solution to precipitate and filter the metal impurities in the solution water, and then circulates to the membrane heat exchanger 7. At this time, the temperature of the compressed gas of the compressor 10 required is relatively high. During the evaporation process, the transport steam flows back to the compressor 10 through the raw liquid steam outlet 77. The steam compressed by the compressor 10 is passed into the second plate preheater. After passing through the gas-liquid separator, the gas is discharged for recovery, and the high-temperature distilled water enters the distilled water tank 11, and is circulated to the first plate preheater 3 again to preheat the stock solution, and then enters the liquid storage tank 13. The solution in the liquid storage tank 13 can be used for diluting the stock solution, flushing the system pipeline or cooling the compressor 10. At this time, a double preheating process of the stock solution is formed, and the system is fully operational. During the full operation of the system, the heat circulates inside the system from beginning to end, ensuring the efficient conversion of the output heat and the efficient output of the concentration process. At the same time, the automatic monitoring process of the system ensures the close coordination between various links, improves efficiency and reduces costs.

[0079] Although the present invention has been described in detail above by general description and specific embodiments, it is obvious to those skilled in the art that some modifications or improvements can be made to the present invention. Therefore, these modifications or improvements made without departing from the spirit of the present invention all belong to the scope of protection claimed by the present invention.

Claims

1. A polymer thin film evaporation concentration system, characterized in that: include Stock liquid pool: the stock liquid pool is sequentially connected to the stock liquid pipelines of the first plate preheater and the second plate preheater through a feed pump, the liquid outlet of the stock liquid pipeline of the second plate preheater is connected to a filter, the filter is connected to a film heat exchanger through a film evaporation circulation pump, and the liquid outlet of the film heat exchanger is connected to the filter; Compressor: the compressed gas outlet of the compressor is connected to the inlet of the heat exchange structure of the membrane heat exchanger, the exhaust channel of the heat exchange structure is connected to the inlet of the compressor, the liquid discharge channel of the heat exchange structure is connected to the heating pipeline of the second plate preheater, the liquid outlet end of the heating pipeline of the second plate preheater is connected to the distilled water tank, the distilled water tank is connected to the heating pipeline of the first plate preheater through a condensate pump, and the outlet of the heating pipeline of the first plate preheater is connected to the liquid storage tank; The liquid outlet end of the thin film evaporation circulation pump is also connected to the concentrated liquid pool; The membrane heat exchanger comprises a shell, a heat exchange structure is arranged inside the shell, a raw liquid inlet, a steam inlet and a non-condensable gas outlet connected to the heat exchange structure are arranged on the shell, the raw liquid inlet is connected to a material diffusion device arranged inside the shell, a raw liquid circulation outlet is arranged at the bottom of the shell, and a raw liquid steam outlet is arranged at the top of the shell; The heat exchange structure comprises a plurality of thin film heat exchange plates arranged in parallel, and the heat exchange structure comprises an air inlet corresponding to the steam inlet, and two air outlets corresponding to the non-condensable gas outlets; The thin film heat exchanger is one of an elliptical, gourd-shaped or S-shaped structure, and the longitudinal sections at the upper and lower ends are arc-shaped structures. The thin film heat exchanger is an integrally formed structure made of a polymer material, and the material is one or a combination of PP, PE, PTFE, FEP, PEEK, and its thickness is 0.05-1mm; The material diffusion device comprises a plurality of evenly distributed liquid distributing pipes, the ends of the liquid distributing pipes are provided with nozzles, the nozzles comprise a connecting portion, a spray barrel is provided on the bottom side of the connecting portion, and a plurality of evenly distributed spray holes are provided on the top circumference of the spray barrel.

2. The polymer thin film evaporation concentration system according to claim 1, characterized in that: The feed pipeline of the feed pump is also connected to the raw liquid pool, and a double feed channel is arranged on the pipeline between the feed pump and the first plate preheater, and the feed pipeline connecting the feed pump to the raw liquid pool is located at the front end of the double feed channel.

3. The polymer thin film evaporation concentration system according to claim 2, characterized in that: The liquid discharge channel of the compressor is connected to a liquid accumulation tank, and the liquid accumulation tank is connected to the distilled water tank through a liquid accumulation pump.

4. The polymer thin film evaporation concentration system according to claim 3, characterized in that: The thin film heat exchanger is also provided with a straight discharge port, and the straight discharge port is connected to the liquid accumulation tank.

5. The polymer thin film evaporation concentration system according to claim 1, characterized in that: The interior of the spray barrel is provided with a partition piece which is in close contact with the interior of the spray barrel and can seal the spray hole, and the bottom side of the partition piece is provided with a supporting spring.

6. The polymer thin film evaporation concentration system according to claim 5, characterized in that: The spray holes are arranged to be tilted downward from the inner side of the spray barrel to the outer side thereof, and the vertical center lines of the spray barrel form an angle of 45°.

Images