Seawater desalination system

Abstract

The invention discloses a seawater desalination system, and relates to the technical field of seawater treatment, and the seawater desalination system is characterized in that seawater evaporation equipment is provided with a concentrated seawater inlet, a water vapor outlet and a sea salt outlet; the combustion chamber is connected with the seawater evaporation equipment and used for heating concentrated seawater in the seawater evaporation equipment, and the combustion chamber is connected with a smoke exhaust pipeline; the pre-distillation equipment is provided with a seawater inlet, a steam outlet and a concentrated seawater outlet, and the concentrated seawater outlet is communicated with the concentrated seawater inlet of the seawater evaporation equipment; the pre-distillation equipment is provided with a flue gas flow channel, an inlet of the flue gas flow channel is communicated with the smoke exhaust pipeline, and an outlet of the flue gas flow channel leads to the flue gas treatment device; according to the technical scheme, the combustion chamber is adopted to continuously heat concentrated seawater in the seawater evaporation equipment, the evaporation efficiency of the seawater is high, meanwhile, the pre-distillation equipment is adopted to pre-evaporate the seawater through exhaust smoke heat of the combustion chamber, the overall energy consumption of the system can be reduced, and therefore the system has the advantages of being high in fresh water yield and energy utilization rate, saving energy, reducing emission and the like.

Description

Technical Field

[0001] The present invention relates to the technical field of seawater treatment, and particularly to a seawater desalination system. Background Art

[0002] As an important strategic resource, increasing the sources and amounts of fresh water is a very important scientific research task. The reserves of seawater are extremely rich, and seawater desalination technology has gradually become a hot research direction in the scientific and technological community.

[0003] For example, Chinese Patent Document CN106698565A discloses a solar heat pump seawater desalination device, which specifically discloses a solar - heat pump - direct absorption seawater desalination device, including: a photovoltaic panel, a heat pump system, and a seawater evaporation device. Among them, the fresh water vapor generated by evaporation through the seawater evaporation device enters the fresh water tank through a heat exchanger. When seawater enters the device, it is first heated for the first time through a heat exchanger, then heated for the second time through a photovoltaic panel, then heated for the third time through a heat pump system, and finally enters the seawater evaporation device for evaporation.

[0004] However, when using the above - mentioned device, the efficiency of seawater desalination is relatively low. Specifically, with the above - mentioned solution, the seawater is first heated three times, and then the high - temperature seawater is directly contacted with ambient air in the seawater evaporation device for heat and moisture exchange. A large amount of seawater evaporates in the seawater evaporation device, turning the ambient air into high - temperature saturated humid air. Since only high - temperature seawater is used as the sole heat source in the seawater evaporation device, the evaporation efficiency of seawater is low.

[0005] Meanwhile, in the above - mentioned device, the heat pump system is used to heat the seawater for the second time, and the compressor in the heat pump system operates continuously, resulting in a problem of high energy consumption. Summary of the Invention

[0006] In view of this, the present invention provides a seawater desalination system to solve the problems of low efficiency and high energy consumption of existing seawater desalination devices.

[0007] In a first aspect, the present invention provides a seawater desalination system, including:

[0008] A seawater evaporation device, having a concentrated seawater inlet, a water vapor outlet, and a sea salt outlet;

[0009] A combustion chamber, connected to the seawater evaporation device, for heating the concentrated seawater in the seawater evaporation device, and a smoke exhaust pipe is connected to the combustion chamber;

[0010] A pre-distillation device, having a seawater inlet, a steam outlet and a concentrated seawater outlet, wherein the concentrated seawater outlet is communicated with the concentrated seawater inlet of the seawater evaporation device; the pre-distillation device has a flue gas flow channel, the inlet of the flue gas flow channel is communicated with the exhaust pipe, and the outlet of the flue gas flow channel leads to a flue gas treatment device.

[0011] In the technical solution of the present invention, a combustion chamber is used to continuously heat the concentrated seawater in the seawater evaporation device, and the evaporation efficiency of seawater is relatively high. At the same time, a pre-distillation device is used to pre-evaporate seawater by using the exhaust heat of the combustion chamber, which can reduce the overall energy consumption of the system. In summary, it has the advantages of high fresh water output, high energy utilization rate, energy conservation and emission reduction.

[0012] Optionally, it further includes: a carbon dioxide storage tank, the outlet of the carbon dioxide storage tank leads to the inside of the pre-distillation device. Through the above setting, carbon dioxide is introduced into the pre-distillation device, and by using the greenhouse effect of carbon dioxide, the temperature inside the pre-distillation device and the pre-evaporation efficiency of seawater can be further improved.

[0013] Optionally, it further includes: a carbon dioxide preheater, which is arranged on the pipeline where the outlet of the flue gas flow channel leads to the flue gas treatment device, and the carbon dioxide storage tank is communicated with the carbon dioxide preheater, and the carbon dioxide preheater is used to preheat at least part of the carbon dioxide introduced into the pre-distillation device. Through the setting of the carbon dioxide preheater, the carbon dioxide is preheated by using the flue gas temperature, which not only effectively utilizes the waste heat of the flue gas, but also further increases the temperature of the carbon dioxide introduced into the pre-distillation device, improving the greenhouse effect of carbon dioxide.

[0014] Optionally, it further includes: a semiconductor heat exchanger, having a condensation channel and a heating channel, the condensation channel is communicated with the steam outlet of the pre-distillation device, the condensation channel has a condensed water outlet and a gas outlet, the inlet of the heating channel is adapted to be communicated with seawater, and the outlet of the heating channel is communicated with the seawater inlet of the pre-distillation device;

[0015] The carbon dioxide preheater has a carbon dioxide gas inlet and a carbon dioxide gas outlet, the gas outlet of the condensation channel of the semiconductor heat exchanger is communicated with the carbon dioxide gas inlet of the carbon dioxide preheater, and the carbon dioxide gas outlet of the carbon dioxide preheater is communicated with the pre-distillation device.

[0016] The carbon dioxide gas outlet of the carbon dioxide preheater is connected to the pre-distillation device through a three-way valve, and the carbon dioxide storage tank is connected to the three-way valve. Through the setting of the three-way valve, when it is necessary to increase the carbon dioxide concentration, the heated carbon dioxide gas and the unheated carbon dioxide gas are mixed at the three-way valve and then jointly enter the pre-distillation device, which can avoid the problem of the carbon dioxide gas entering the pre-distillation device being too cold and ensure the stability of the pre-evaporation of seawater.

[0017] Optionally, it further includes: a turbine and a generator connected to the turbine, and the inlet of the turbine is connected to the water vapor outlet of the seawater evaporation device. Through the setting of the turbine, the water vapor generated by the seawater evaporation device can be used for power generation, and the electric energy generated by the generator can be used to drive equipment such as pumps and fans in the system, thereby further improving the energy conservation and emission reduction effect.

[0018] Optionally, it further includes: a steam heat exchanger having a first heat exchange channel and a second heat exchange channel. The inlet of the first heat exchange channel is connected to the outlet of the turbine, the inlet of the second heat exchange channel is used to be connected to seawater, and the outlet of the second heat exchange channel is connected to the seawater inlet of the pre-distillation device; through the setting of the steam heat exchanger, the waste heat of the steam participating in driving the turbine to rotate can be used to pre-heat the seawater, thereby improving the subsequent evaporation efficiency of the seawater.

[0019] Optionally, the pre-distillation device has an inner layer, an outer layer, and a sandwich layer located between the inner layer and the outer layer, and a flue gas flow channel is formed in the sandwich layer; the sandwich structure increases the surface area of contact between the flue gas and the pre-distillation device, and more heat can be transferred through a larger area, thereby improving the overall heat exchange efficiency. In addition, the sandwich structure plays a certain heat insulation role and reduces the loss of heat in the pre-distillation device to the external environment.

[0020] A condenser lens is provided above the pre-distillation device, and the condenser lens is used to concentrate sunlight into the pre-distillation device. Through the setting of the condenser lens, a large area of sunlight can be converged into a smaller area inside the pre-distillation device. In this way, the solar radiation intensity received per unit area can be significantly increased, providing more sufficient energy for the distillation process. The solar energy converged by the condenser lens can make the materials in the pre-distillation device reach the boiling point faster and accelerate the distillation speed.

[0021] Optionally, it further includes: a solar energy device, which has a photovoltaic module and a preheating pipe. The preheating pipe is arranged on the back of the photovoltaic module. The inlet of the preheating pipe is used to connect with seawater, and the outlet of the preheating pipe is communicated with the pre-distillation device. The seawater in the preheating pipe is used to cool down the photovoltaic module. By arranging the preheating pipe on the back of the photovoltaic module, the seawater flowing in the pipe can effectively absorb the heat generated when the photovoltaic module works. During the operation of the photovoltaic module, an increase in temperature will lead to a decrease in its power generation efficiency. Through the circulating flow of seawater to take away the heat, the photovoltaic module is maintained within a relatively low and appropriate working temperature range, thereby improving the power generation efficiency of the photovoltaic module. While cooling down the photovoltaic module, the seawater itself absorbs heat to achieve preheating. The preheated seawater enters the heating channel of the semiconductor heat exchanger, reducing the energy consumed by the semiconductor heat exchanger to heat the seawater to the required temperature. This way of cascaded utilization of energy improves the overall energy utilization efficiency of the entire system. Since the energy consumption of the semiconductor heat exchanger is reduced, the operating cost of the entire system also decreases accordingly.

[0022] Optionally, it further includes: a reverse osmosis device. The inlet of the reverse osmosis device is used to connect with seawater. The first outlet of the reverse osmosis device is communicated with a fresh water storage device, and the second outlet of the reverse osmosis device is communicated with the seawater evaporation device. By combining the reverse osmosis device with the seawater evaporation device, multi-stage utilization of seawater is achieved. The reverse osmosis device first preliminarily treats the seawater, separates out fresh water and enters the fresh water storage device to meet the basic needs of life or industry for fresh water. The remaining concentrated seawater is then transported to the seawater evaporation device through the second outlet. In the seawater evaporation device, the concentrated seawater further evaporates to extract the remaining fresh water in it, thereby improving the overall utilization rate of seawater resources. Compared with relying only on a single seawater treatment method, the system reduces the direct discharge of wastewater such as concentrated brine. In the traditional seawater desalination process, the direct discharge of a large amount of concentrated brine back into the ocean may have a certain impact on the marine ecological environment, such as changing the salinity of local sea areas. While this system secondary-treats the concentrated brine generated by the reverse osmosis device, reducing the total amount of wastewater discharge and alleviating the pressure on the marine ecosystem.

[0023] Optionally, it further includes: a storage battery for supplying electrical energy to the semiconductor heat exchanger, and the storage battery is electrically connected to at least one of the power grid, a wind power generation device, a solar power generation device, and a tidal energy power generation device. The storage battery can be electrically connected to at least one of the power grid, a wind power generation device, a solar power generation device, and a tidal energy power generation device, thus forming a power supply mode in which multiple energy sources complement each other. Different energy sources have different characteristics. For example, solar energy is affected by day and night and weather, wind energy is affected by wind speed and stability, and tidal energy is restricted by tidal cycles. By integrating these energy sources through the storage battery, when one energy source is insufficient, it can be quickly switched to other energy sources for charging to ensure that there is always enough power to supply the semiconductor heat exchanger. Description of the Drawings

[0024] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for the description of the specific embodiments or the prior art. Obviously, the following drawings are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0025] Figure 1 The front view of a seawater desalination system provided by an embodiment of the present invention;

[0026] Figure 2 For Figure 1 The internal structure schematic diagram of the pre-distillation device shown in

[0027] Figure 3 The front view of the second seawater desalination system provided by an embodiment of the present invention;

[0028] Figure 4 For Figure 3 The internal structure schematic diagram of the semiconductor heat exchanger shown in

[0029] Figure 5 The front view of the third seawater desalination system provided by an embodiment of the present invention;

[0030] Figure 6 The front view of the fourth seawater desalination system provided by an embodiment of the present invention;

[0031] Figure 7 For Figure 6 The enlarged view of the solar power generation device shown in

[0032] Description of the Reference Numerals:

[0033] 1. Seawater evaporation equipment; 2. Concentrated seawater inlet; 3. Water vapor outlet; 4. Sea salt outlet; 5. Combustion chamber; 6. Exhaust pipe; 7. Pre-distillation equipment; 8. Seawater inlet; 9. Steam outlet; 10. Concentrated seawater outlet; 11. Interlayer; 12. Condensing lens; 13. Carbon dioxide storage tank; 14. Carbon dioxide preheater; 15. Semiconductor heat exchanger; 16. Condensation channel; 17. Heating channel; 18. Condensate outlet; 19. Gas outlet; 20. Turbine; 21. Generator; 22. Steam heat exchanger; 23. Solar power generation device; 24. Photovoltaic module; 25. Preheating pipe; 26. Reverse osmosis device; 27. Freshwater storage device; 28. Storage battery; 29. Power grid; 30. Wind power generation device; 31. Tidal energy power generation device; 32. Seawater storage device. Detailed implementation manners

[0034] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Apparently, the described embodiments are some but not all of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0035] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is 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 should not be construed as a limitation of the present invention. In addition, the terms "first", "second", and "third" are only used for descriptive purposes and should not be construed as indicating or implying relative importance.

[0036] In the description of the present invention, it should be noted that unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" 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 directly connected, or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0037] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0038] Such as Figure 1As shown in the figure, a specific implementation of the seawater desalination system provided in this embodiment includes: a seawater evaporation device 1, a combustion chamber 5, and a pre-distillation device 7. The seawater evaporation device 1 has a concentrated seawater inlet 2, a water vapor outlet 3, and a sea salt outlet 4; the combustion chamber 5 is connected to the seawater evaporation device 1 for heating the concentrated seawater in the seawater evaporation device 1, and a smoke exhaust pipe 6 is connected to the combustion chamber 5; the pre-distillation device 7 has a seawater inlet 8, a steam outlet 9, and a concentrated seawater outlet 10, and the concentrated seawater outlet 10 is communicated with the concentrated seawater inlet 2 of the seawater evaporation device 1; the pre-distillation device 7 has a smoke flow channel, the inlet of the smoke flow channel is communicated with the smoke exhaust pipe 6, and the outlet of the smoke flow channel leads to a flue gas treatment device. Among them, the flue gas treatment device may specifically include: a desulfurization and denitrification device, a chimney, etc., which are not specifically limited here. An induced draft fan may be connected to the smoke exhaust pipe 6 to increase the flue gas flow rate.

[0039] In addition, in order to increase the amount of seawater in the seawater evaporation device 1, a second seawater inlet 8 may also be provided on the seawater evaporation device 1, and seawater that has not passed through the pre-distillation device 7 is connected through the second seawater inlet 8, so as to increase the amount of seawater in the seawater evaporation device 1.

[0040] The seawater desalination system provided in this embodiment uses the combustion chamber 5 to continuously heat the concentrated seawater in the seawater evaporation device 1, and has a relatively high evaporation efficiency for seawater. At the same time, the pre-distillation device 7 is used to pre-evaporate the seawater using the exhaust heat of the combustion chamber 5, which can reduce the overall energy consumption of the system. Therefore, it has the advantages of high fresh water output, high energy utilization rate, energy conservation and emission reduction, etc.

[0041] As Figure 2 shown, in the seawater desalination system provided in this embodiment, the pre-distillation device 7 has an inner layer, an outer layer, and a sandwich layer 11 located between the inner layer and the outer layer, and the smoke flow channel is formed in the sandwich layer 11; through the setting of the sandwich layer 11 structure, the surface area of contact between the flue gas and the pre-distillation device 7 is increased, and more heat can be transferred through a larger area, thereby improving the overall heat exchange efficiency. In addition, the sandwich layer 11 structure can also play a certain heat insulation role, reducing the loss of heat in the pre-distillation device 7 to the external environment. Of course, the above description is not restrictive. In some alternative embodiments, the smoke flow channel may also adopt other forms, for example, it may be set in the form of multiple groups of pipes, etc.

[0042] As Figure 2As shown in the figure, in the seawater desalination system provided in this embodiment, a condenser lens 12 is provided above the pre-distillation device 7, and the condenser lens 12 is used to concentrate sunlight into the pre-distillation device 7. Through the arrangement of the condenser lens 12, a large area of sunlight can be converged into a smaller area inside the pre-distillation device 7. In this way, the solar radiation intensity received per unit area can be significantly increased, providing more sufficient energy for the distillation process. The solar energy converged by the condenser lens 12 can cause the materials inside the pre-distillation device 7 to reach the boiling point faster, accelerating the distillation speed.

[0043] As Figure 3 , Figure 4 shown, in some embodiments, it further includes: a semiconductor heat exchanger 15. The semiconductor heat exchanger 15 has a condensation channel 16 and a heating channel 17. The condensation channel 16 is communicated with the steam outlet 9 of the pre-distillation device 7. The condensation channel 16 has a condensed water outlet 18 and a gas outlet 19. The inlet of the heating channel 17 is adapted to be communicated with seawater, and the outlet of the heating channel 17 is communicated with the seawater inlet 8 of the pre-distillation device 7. Using the semiconductor heat exchanger 15 to preheat seawater can further increase the temperature of the seawater entering the pre-distillation device 7 and increase the evaporation amount in the pre-distillation device 7. Using the semiconductor heat exchanger 15 to condense steam can further improve the fresh water production efficiency and increase the fresh water output. Specifically, the semiconductor heat exchanger 15 is based on the Peltier effect, and it has semiconductor thermoelectric elements, which are composed of P-type semiconductors, N-type semiconductors, insulating heat conductors, and conductors. The insulating heat conductor is composed of materials with electrical insulation and high thermal conductivity, such as ceramics and glass. The N-type semiconductor is a semiconductor mainly based on electron conduction, such as a silicon semiconductor containing a pentavalent element arsenic. The P-type semiconductor is a semiconductor mainly based on hole conduction, such as a silicon semiconductor containing a trivalent element boron. The heating end of the semiconductor thermoelectric element is close to the heating channel 17, and the cooling end of the semiconductor thermoelectric element is close to the condensation channel 16. The semiconductor thermoelectric element recovers and utilizes the waste heat of the water vapor in the condensation channel 16 and uses it to preheat the seawater in the heating channel 17.

[0044] Of course, the above description is not restrictive. In some alternative embodiments, the semiconductor heat exchanger 15 can be omitted. The steam discharged from the steam outlet 9 of the distillation device 7 can be condensed by natural cooling or by devices such as condensers.

[0045] As Figure 3As shown, in some embodiments, it further includes: a turbine 20 and a generator 21 connected to the turbine 20. The inlet of the turbine 20 is communicated with the water vapor outlet 3 of the seawater evaporation device 1. Through the arrangement of the turbine 20, the water vapor generated by the seawater evaporation device 1 can be used for power generation, and the electric energy generated by the generator 21 can be used to drive devices such as pumps and fans in the system, thereby further improving the energy conservation and emission reduction effect.

[0046] As Figure 3 shown, in some embodiments, it further includes: a steam heat exchanger 22. The steam heat exchanger 22 has a first heat exchange channel and a second heat exchange channel. The inlet of the first heat exchange channel is communicated with the outlet of the turbine 20, the inlet of the second heat exchange channel is communicated with the heating channel 17 of the semiconductor heat exchanger 15, and the outlet of the second heat exchange channel is communicated with the seawater inlet 8 of the pre-distillation device 7. Through the arrangement of the steam heat exchanger 22, the waste heat of the steam participating in driving the rotation of the turbine 20 can be used to pre-heat the seawater, thereby improving the subsequent evaporation efficiency of the seawater.

[0047] As Figure 3 shown, the outlet of the first heat exchange channel is communicated with the condensation channel 16 of the semiconductor heat exchanger 15. After the steam passes through the condensation channel 16 of the semiconductor heat exchanger 15, the steam can be quickly condensed, so as to quickly produce fresh water for collection. Of course, the above description is not restrictive. In some alternative embodiments, the steam heat exchanger 22 can be omitted.

[0048] As Figure 5 shown, in some embodiments, it further includes: a carbon dioxide storage tank 13. The outlet of the carbon dioxide storage tank 13 leads to the inside of the pre-distillation device 7. Through the above arrangement, carbon dioxide is introduced into the pre-distillation device 7. By using the greenhouse effect of carbon dioxide, the temperature inside the pre-distillation device 7 and the pre-evaporation efficiency of the seawater can be further improved. Specifically, the outlet of the carbon dioxide storage tank 13 can directly lead to the inside of the pre-distillation device 7, or the carbon dioxide can be pre-heated by a pre-heater and then introduced into the pre-distillation device 7, so as to improve the greenhouse effect of carbon dioxide. Of course, the above description is not restrictive. In some alternative embodiments, the carbon dioxide storage tank 13 can be omitted.

[0049] As Figure 5As shown, in some embodiments, it further includes: a carbon dioxide preheater 14, which is arranged on the pipeline where the outlet of the flue gas flow path leads to the flue gas treatment device. The carbon dioxide preheater 14 is used to preheat at least part of the carbon dioxide introduced into the pre-distillation device 7. Through the setting of the carbon dioxide preheater 14, the carbon dioxide is preheated by using the flue gas temperature, which not only effectively utilizes the waste heat of the flue gas, but also further increases the temperature of the carbon dioxide introduced into the pre-distillation device 7, enhancing the greenhouse effect of the carbon dioxide.

[0050] Of course, the above description is not restrictive. In some alternative embodiments, the carbon dioxide preheater 14 can also preheat the carbon dioxide in other ways, such as by using electric heating.

[0051] As Figure 5 shown, in this embodiment, the carbon dioxide preheater 14 has a carbon dioxide gas inlet and a carbon dioxide gas outlet 19. The gas outlet 19 of the condensation channel 16 of the semiconductor heat exchanger 15 is communicated with the carbon dioxide gas inlet of the carbon dioxide preheater 14, and the carbon dioxide gas outlet 19 of the carbon dioxide preheater 14 is communicated with the pre-distillation device 7. Through this setting, the recycling of carbon dioxide is realized, and it is ensured that the carbon dioxide flowing back to the pre-distillation device 7 has a certain temperature, guaranteeing the stability of the operation of the pre-distillation device 7.

[0052] As Figure 5 shown, in this embodiment, the carbon dioxide gas outlet 19 of the carbon dioxide preheater 14 is communicated with the pre-distillation device 7 through a three-way valve, and the carbon dioxide storage tank 13 is communicated with the three-way valve. Through the setting of the three-way valve, when it is necessary to increase the carbon dioxide concentration, the heated carbon dioxide gas and the unheated carbon dioxide gas are mixed at the three-way valve and then jointly enter the pre-distillation device 7, which can avoid the problem of the carbon dioxide gas entering the pre-distillation device 7 being too cold and guarantee the stability of the pre-evaporation of seawater.

[0053] As Figure 6 、 Figure 7As shown, in some embodiments, it further includes: a solar energy device, the solar energy device having a photovoltaic module 24 and a preheating pipe 25, the preheating pipe 25 being disposed on the back surface of the photovoltaic module 24, an inlet of the preheating pipe 25 being used for connecting with seawater, and an outlet of the preheating pipe 25 communicating with an inlet of a heating channel 17 of the semiconductor heat exchanger 15. The seawater in the preheating pipe 25 can cool down the photovoltaic module 24. Specifically, by disposing the preheating pipe 25 on the back surface of the photovoltaic module 24, the seawater flowing in the pipe can effectively absorb the heat generated when the photovoltaic module 24 operates. During the operation of the photovoltaic module 24, an increase in temperature will lead to a decrease in its power generation efficiency. By circulating the seawater to carry away the heat, the photovoltaic module 24 is maintained within a relatively low and appropriate operating temperature range, thereby improving the power generation efficiency of the photovoltaic module 24. In addition, while the seawater cools down the photovoltaic module 24, it absorbs heat itself to achieve preheating. The preheated seawater enters the heating channel 17 of the semiconductor heat exchanger 15, reducing the energy consumed by the semiconductor heat exchanger 15 to heat the seawater to the required temperature. This way of cascaded utilization of energy improves the overall energy utilization efficiency of the entire system. Since the energy consumption of the semiconductor heat exchanger 15 is reduced, the operating cost of the entire system is also reduced accordingly.

[0054] As Figure 6 shown, in some embodiments, it further includes: a reverse osmosis device 26, an inlet of the reverse osmosis device 26 being used for connecting with seawater, a first outlet of the reverse osmosis device 26 communicating with a fresh water storage device 27, and a second outlet of the reverse osmosis device 26 communicating with the seawater evaporation device 1. A reverse osmosis membrane is disposed inside the reverse osmosis device 26, and the type of the reverse osmosis membrane includes at least one of cellulose acetate membrane, aromatic polyamide membrane, aromatic polyhydrazide membrane, etc. By combining the reverse osmosis device 26 with the seawater evaporation device 1, multi-stage utilization of seawater is achieved. The reverse osmosis device 26 first preliminarily treats the seawater, separates out fresh water and sends it into the fresh water storage device 27 to meet the basic needs for fresh water in life, industry, etc. The remaining concentrated seawater is then transported to the seawater evaporation device 1 through the second outlet. In the seawater evaporation device 1, the concentrated seawater further evaporates to extract the remaining fresh water therein, thereby improving the overall utilization rate of seawater resources. Compared with relying solely on a single seawater treatment method, this system reduces the direct discharge of wastewater such as concentrated brine. In the traditional seawater desalination process, a large amount of concentrated brine directly discharged back into the ocean may have a certain impact on the marine ecological environment, such as changing the salinity of local sea areas, etc. While this system performs secondary treatment on the concentrated brine generated by the reverse osmosis device 26, reducing the total amount of wastewater discharge and alleviating the pressure on the marine ecology. Of course, the above description is not restrictive. In some alternative embodiments, the reverse osmosis device 26 can be omitted.

[0055] As Figure 6As shown, in some embodiments, it further includes: a storage battery 28 for supplying electrical energy to the semiconductor heat exchanger 15, and the storage battery 28 is electrically connected to at least one of the power grid 29, the wind power generation device 30, the solar power generation device 23, and the tidal energy power generation device 31. The storage battery 28 can be electrically connected to at least one of the power grid 29, the wind power generation device 30, the solar power generation device 23, and the tidal energy power generation device 31, thus forming a power supply mode in which multiple energy sources complement each other. Different energy sources have different characteristics. For example, solar energy is affected by day and night and weather, wind energy is affected by wind speed and stability, and tidal energy is restricted by the tidal cycle. By integrating these energy sources through the storage battery 28, when one energy source is insufficient, it can be quickly switched to other energy sources for charging to ensure that there is always enough power to supply the semiconductor heat exchanger 15. Of course, the above description is not restrictive. In some alternative embodiments, the storage battery 28 can be omitted, and the power grid 29 can be directly used to supply power to the semiconductor heat exchanger 15.

[0056] Working principle:

[0057] As Figure 6 shown, seawater can first be stored in the seawater storage device 32, and then part of the seawater is filtered through the reverse osmosis device 26. The fresh water enters the fresh water storage device 27, and the concentrated seawater enters the seawater evaporation device 1.

[0058] Another part of the seawater sequentially passes through the preheating pipe 25 of the solar power generation device 23, the heating channel 17 of the semiconductor heat exchanger 15, the second heat exchange channel of the steam heat exchanger 22, and the pre-distillation device 7, and then a part of it is evaporated in the pre-distillation device 7. The evaporated water vapor enters the condensation channel 16 of the semiconductor heat exchanger 15. After the water vapor condenses, it forms fresh water and enters the fresh water storage device 27; the remaining concentrated seawater enters the seawater evaporation device 1.

[0059] In the seawater evaporation device 1, the heat generated by the combustion of biomass fuel in the combustion chamber 5 is used to heat the concentrated seawater to evaporate it. The evaporated water vapor sequentially enters the turbine 20 to do work, the first heat exchange channel of the steam heat exchanger 22, and the condensation channel 16 of the semiconductor heat exchanger 15, and then condenses in the condensation channel 16. After the water vapor condenses, it forms fresh water and enters the fresh water storage device 27.

[0060] The flue gas generated by the combustion of biomass fuel in the combustion chamber 5 enters the interlayer 11 of the pre-distillation device 7 through the smoke exhaust pipe 6. Thus, in the pre-distillation device 7, under the combined action of the residual temperature of the flue gas and the solar heat energy of the condenser lens 12, the seawater is heated.

[0061] In addition, in the pre-distillation device 7, carbon dioxide is introduced, and by utilizing the greenhouse effect of carbon dioxide, the heating efficiency of the seawater in the pre-distillation device 7 is improved.

[0062] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations fall within the scope defined by the present invention.

Claims

1. A seawater desalination system, characterized in that, Comprising: A seawater evaporation device (1), having a concentrated seawater inlet (2), a water vapor outlet (3), and a sea salt outlet (4); A combustion chamber (5), connected to the seawater evaporation device (1) for heating the concentrated seawater in the seawater evaporation device (1), and a smoke exhaust pipe (6) is connected to the combustion chamber (5); A pre-distillation device (7), having a seawater inlet (8), a steam outlet (9), and a concentrated seawater outlet (10), the concentrated seawater outlet (10) is communicated with the concentrated seawater inlet (2) of the seawater evaporation device (1); the pre-distillation device (7) has a smoke gas flow channel, the inlet of the smoke gas flow channel is communicated with the smoke exhaust pipe (6), and the outlet of the smoke gas flow channel leads to a flue gas treatment device.

2. The seawater desalination system according to claim 1, characterized in that, Further comprising: A semiconductor heat exchanger (15), having a condensation channel (16) and a heating channel (17), the condensation channel (16) is communicated with the steam outlet (9) of the pre-distillation device (7), the condensation channel (16) has a condensed water outlet (18) and a gas outlet (19), the inlet of the heating channel (17) is adapted to be communicated with seawater, and the outlet of the heating channel (17) is communicated with the seawater inlet (8) of the pre-distillation device (7).

3. The seawater desalination system according to claim 1, characterized in that, Further comprising: A carbon dioxide storage tank (13), the outlet of the carbon dioxide storage tank (13) leads into the pre-distillation device (7).

4. The seawater desalination system according to claim 3, characterized in that, Further comprising: A carbon dioxide preheater (14), arranged on the pipe where the outlet of the smoke gas flow channel leads to the flue gas treatment device, the carbon dioxide storage tank (13) is communicated with the carbon dioxide preheater (14), and at least part of the carbon dioxide introduced into the pre-distillation device (7) is preheated through the carbon dioxide preheater (14).

5. The seawater desalination system according to claim 1, wherein Further comprising: A turbine (20) and a generator (21) connected to the turbine (20), the inlet of the turbine (20) is communicated with the water vapor outlet (3) of the seawater evaporation device (1).

6. The seawater desalination system according to claim 5, wherein, Further comprising: A steam heat exchanger (22), having a first heat exchange channel and a second heat exchange channel, the inlet of the first heat exchange channel is communicated with the outlet of the turbine (20), the inlet of the second heat exchange channel communicated is adapted to be communicated with seawater, and the outlet of the second heat exchange channel is communicated with the seawater inlet (8) of the pre-distillation device (7).

7. The seawater desalination system according to any one of claims 1-6, characterized in that, The pre-distillation device (7) has an inner layer, an outer layer, and a sandwich layer (11) located between the inner layer and the outer layer, and the smoke gas flow channel is formed in the sandwich layer (11); A condenser lens (12) is provided above the pre-distillation device (7), and sunlight is concentrated into the pre-distillation device (7) through the condenser lens (12).

8. The seawater desalination system according to any one of claims 1-6, characterized in that, Further comprising: A solar energy device, the solar energy device has a photovoltaic module (24) and a preheating pipe (25), the preheating pipe (25) is arranged on the back of the photovoltaic module (24), the inlet of the preheating pipe (25) is used to be connected with seawater, the outlet of the preheating pipe (25) is communicated with the pre-distillation device (7), and the seawater in the preheating pipe (25) is used to cool down the photovoltaic module (24).

9. The seawater desalination system according to any one of claims 1-6, characterized in that, Further comprising: A reverse osmosis device (26), the inlet of the reverse osmosis device (26) is used to communicate with seawater, the first outlet of the reverse osmosis device (26) is communicated with a fresh water storage device (27), and the second outlet of the reverse osmosis device (26) is communicated with the seawater evaporation device (1).

10. The seawater desalination system according to claim 2, characterized in that, It further includes: A storage battery (28) for supplying electric energy to the semiconductor heat exchanger (15), and the storage battery (28) is electrically connected to at least one of a power grid (29), a wind power generation device (30), a solar power generation device (23), and a tidal energy power generation device (31).

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