A solar sea water desalination cogeneration system

Abstract

The application discloses a solar energy seawater desalination cogeneration system, and relates to the technical field of seawater desalination, in particular to a system for coupling photovoltaic energy storage, electrostatic atomization, heat exchange and condensation, and the system is powered by photovoltaic energy storage, electrostatic atomization is used to improve the seawater evaporation efficiency, and steam waste heat is fully utilized in the heat exchange and condensation process.

Description

Technical Field

[0001] This invention relates to the field of charged spray and seawater desalination technology, specifically to a solar-powered seawater desalination co-production system. Background Technology

[0002] Seawater desalination is a water treatment technology that uses specific processes to remove most of the salts from seawater, making it meet the standards for domestic and industrial water use. Conventional methods include distillation, reverse osmosis, dialysis, ion exchange, and freezing. Seawater desalination is not limited by climate or time and space conditions, and relying on inexhaustible seawater resources, it can fundamentally solve the problem of water scarcity.

[0003] However, there are still many problems to be solved in seawater desalination. For example, seawater desalination is a major investment project with high consumption and high energy consumption, and it is mainly concentrated around developed cities.

[0004] Conventional seawater desalination equipment uses mechanical atomization, which means that the liquid surface is broken by external force, forming many small particles. This method is energy-intensive and the droplets are not evenly dispersed.

[0005] Therefore, it is of great significance to provide a seawater desalination device with a simple energy design structure and a wide range of applications. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this application proposes a solar-powered seawater desalination cogeneration system. This system couples photovoltaic energy storage, electrostatic atomization, and heat exchange condensation. It utilizes photovoltaic energy storage to power the system, electrostatic atomization to improve seawater evaporation efficiency, and fully leverages waste heat from the steam during the heat exchange condensation process. This system has a simple structure and a wide range of applications.

[0007] The technical solution adopted in this invention is as follows: A solar-powered seawater desalination cogeneration system includes: a photovoltaic energy storage system, an atomizing evaporation system, a heat exchange and condensation system, and a re-evaporation system; The atomization evaporation system includes a water storage heating tank, an atomization heating evaporation chamber, and an electrostatic atomization unit. The water storage heating tank heats the input seawater. The electrostatic atomization unit is located between the water storage heating tank and the atomization heating evaporation chamber. The electrostatic atomization unit breaks the heated seawater in the water storage heating tank into droplets with micron or even nanometer-sized inner diameters and sprays them into the atomization heating evaporation chamber. Water vapor and low-concentration brine are obtained by evaporation in the atomization heating evaporation chamber. The heat exchange and condensation system condenses the water vapor generated by the atomizing evaporation system into fresh water. The re-evaporation system inputs low-concentration brine into the atomizing evaporation system for re-evaporation to obtain high-concentration brine. The photovoltaic energy storage system converts solar energy into electrical energy and supplies power to the electrical equipment in the atomization evaporation system, heat exchange condensation system, and re-evaporation system.

[0008] Furthermore, the atomizing heating evaporation chamber is provided with a constriction, one side of which is provided with a waterproof and breathable membrane, and the other side is connected to a heat exchange and condensation system. The waterproof and breathable membrane is used to separate the steam from the atomized droplets before they are fed into the heat exchange and condensation system.

[0009] Furthermore, the electrostatic atomization unit includes a high-voltage electrostatic generator, an annular electrode, and a nozzle; the annular electrode is connected to the high-voltage electrostatic generator, forming a high-voltage electric field around the annular electrode; the nozzle is located at the center of the annular electrode; the nozzle inlet is connected to the water storage heating tank, and the nozzle outlet faces the atomization heating evaporation chamber.

[0010] Furthermore, the heat exchange and condensation system includes a heat exchanger, a condenser tube, and a fresh water collection bottle; the steam inlet of the heat exchanger is connected to the atomizing heating evaporation chamber through a pipeline, and the steam outlet of the heat exchanger is connected to the condenser tube and the fresh water collection bottle in sequence; the condenser tube is placed in a condensation box.

[0011] Furthermore, the condenser is connected to the heat exchanger and the water storage heating tank in sequence through pipelines. Seawater is used as the heat exchange medium in both the condenser and the heat exchanger. The seawater is preheated in multiple stages by the condenser and the heat exchanger before being fed into the water storage heating tank.

[0012] Furthermore, the re-evaporation system includes a low-concentration brine collection tank and a high-concentration brine collection tank. The low-concentration brine collection tank is connected to the bottom of the atomizing heating evaporation chamber and is used to receive the low-concentration brine generated by the atomizing heating evaporation chamber. The low-concentration brine collection tank is also connected to the atomizing evaporation system to input the low-concentration brine into the atomizing evaporation system for secondary evaporation. The high-concentration brine collection tank is used to collect the high-concentration brine generated after secondary evaporation.

[0013] Furthermore, the photovoltaic energy storage system includes solar panels and energy storage batteries. The solar panels convert solar energy into electrical energy and are connected to the energy storage batteries via wires. The converted electrical energy can be stored, and the energy storage batteries power the electrical equipment in the system. Furthermore, the photovoltaic energy storage system is equipped with an orientation adjustment system to adjust the orientation of the solar panels.

[0014] Furthermore, the seawater inlet and outlet of the condenser are both equipped with filters.

[0015] Furthermore, the outer walls of the water storage heating box and the atomizing evaporation chamber are both covered with an insulating layer.

[0016] The beneficial effects of this invention are: 1. This invention uses a photovoltaic power generation device to replace ordinary power sources and stores electrical energy through batteries to achieve seawater desalination throughout the day. It can be placed on ships and islands to provide fresh water for offshore work and achieve the goals of high efficiency, energy saving, environmental protection and zero carbon emissions.

[0017] 2. The electrostatic atomizing multi-nozzle seawater desalination device of the present invention can generate a "simple-jet" atomization mode with a large flow rate and droplet size in the sub-millimeter range, which makes up for the two limitations of the early design: the cone jet mode is difficult to obtain high liquid flux and the aqueous solution is difficult to form a stable cone jet, thus greatly improving the efficiency of seawater desalination.

[0018] 3. This invention combines electrostatic atomization technology with photovoltaic power supply technology and charged droplet evaporation technology. It utilizes the good monodispersity of droplets generated by electrostatic atomization technology to improve the working efficiency of the evaporation and distillation process in seawater desalination, increase the gas-liquid contact area and induce droplet surface to achieve the purpose of increasing evaporation efficiency.

[0019] 4. The re-evaporation device of the present invention can perform secondary desalination of the treated brine, greatly improving the utilization rate and desalination effect of seawater, and obtaining highly concentrated brine by-products. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of a small-scale solar-powered seawater desalination co-production system proposed in this invention.

[0021] Figure 2 This is a schematic diagram of the ring electrode structure in an atomizing evaporation system.

[0022] Figure 3 This is a flowchart of the desalination process in a solar-powered seawater desalination cogeneration system.

[0023] In the diagram: 1-Solar panel; 2-Motor; 3-Connecting rod; 4-Storage battery; 5-Water storage heating tank; 6-Ring electrode; 7-High voltage electrostatic generator; 8-Nozzle; 9-Narrow neck; 10-Waterproof and breathable membrane; 11-Atomizing heating evaporation chamber; 12-Pressure relief valve; 13-Low concentration brine collection tank; 14-Pressure sensor; 15-Proportional valve; 16-High concentration brine collection tank; 17-Valve; 18-Interface; 19-Injection pump; 20-Air pump; 21-Plate heat exchanger; 22-First actuating valve; 23-Second actuating valve; 24-Condenser tube; 25-Condenser box; 26-Fresh water collection bottle. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the invention.

[0025] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0026] Figure 1 This is a schematic diagram of the structure of a solar-powered seawater desalination co-production system proposed in this invention. The system includes: a photovoltaic energy storage system, an atomizing evaporation system, a heat exchange and condensation system, and a re-evaporation system. The photovoltaic energy storage system converts solar energy into electrical energy for storage and provides energy for the operation of the entire system. The atomizing evaporation system electrostatically atomizes heated seawater to obtain water vapor and low-concentration brine. The heat exchange and condensation system condenses the water vapor generated by the atomizing evaporation system into fresh water. The re-evaporation system re-evaporates the low-concentration brine to obtain high-concentration brine.

[0027] The photovoltaic energy storage system includes a solar panel 1 and an energy storage battery 4. The solar panel 1 converts solar energy into electrical energy and connects to the energy storage battery 4 through wires. The converted electrical energy can be stored and the energy storage battery 4 supplies power to the electrical equipment in the system.

[0028] More specifically, to improve the power generation efficiency of the photovoltaic energy storage system, this invention equips the photovoltaic energy storage system with an orientation adjustment system, enabling it to automatically track sunlight. The orientation adjustment system includes a spectrometer, a microcontroller, a connecting rod 3, a rotating component, and a motor 2. The spectrometer is located inside the solar panel 1 and is used to detect light intensity and identify the direction of light intensity. The bottom of the solar panel 1 is connected to the connecting rod 3. The microcontroller is placed inside the connecting rod 3 and is signal-connected to the spectrometer, receiving the light intensity obtained by the spectrometer and outputting a turning command based on the light intensity. The connecting rod 3 is connected to the motor 2 via the rotating component, and the motor 2 is signal-connected to the microcontroller. Based on the turning command output by the microcontroller, the motor drives the rotating component to rotate the connecting rod 3 and the solar panel 1 together. The solar panel 1 always ensures that the sunlight is perpendicular to the surface of the collector tube, maximizing the light intensity received by the solar panel 1, thereby improving power generation efficiency. In this embodiment, the rotating component can be driven by a gear ring.

[0029] The atomization evaporation system includes a water storage and heating tank 5, an atomization heating and evaporation chamber 11, and an electrostatic atomization unit. The water storage and heating tank 5 is connected to a seawater supply unit via an injection pump 19 and pipelines, allowing seawater to be treated to be fed into it. The water storage and heating tank 5 is equipped with a heater to heat the seawater, preparing it for electrostatic atomization and evaporation in the atomization heating and evaporation chamber 11. The electrostatic atomization unit is located between the water storage and heating tank 5 and the atomization heating and evaporation chamber 11. This unit breaks the heated seawater in the water storage and heating tank 5 into droplets with micron or even nanometer-sized internal diameters, which are then sprayed into the atomization heating and evaporation chamber 11. The atomization heating and evaporation chamber 11 is equipped with a heater to accelerate seawater evaporation.

[0030] More specifically, in conjunction with the appendix Figure 2 The electrostatic atomization unit includes a high-voltage electrostatic generator 7, an annular electrode 6, and nozzles 8. The positive terminal of the high-voltage electrostatic generator 7 is connected to the annular electrode 6, and the negative terminal is grounded. Multiple annular electrodes 6 can be set and interconnected, forming a high-voltage electric field around each annular electrode 6. The annular electrodes 6 are embedded in non-metallic materials to ensure insulation. The annular electrodes 6 surround each nozzle 8 but do not contact it. After being heated, the seawater flows through the high-voltage electric field of the nozzles 8 and is broken into droplets with a particle size of micrometers or even nanometers. These droplets are then sprayed onto the inner wall of the atomization heating evaporation chamber 11, awaiting further heating and evaporation.

[0031] More specifically, the inlet inner diameter of each nozzle 8 is less than 1.2 mm, and the optimal flow rate q for each nozzle 8 to generate a jet ensures that the flow state of the nozzle 8 is a jet state. Therefore, the outlet flow rate Q of the injection pump 19 is Q=nq, where n is the number of nozzles 8, thus determining the outlet flow rate of the injection pump 19.

[0032] The heat exchange and condensation system includes a plate heat exchanger 21, a condenser tube 24, and a fresh water collection bottle 26. The steam inlet of the plate heat exchanger 21 is connected to the atomizing heating evaporation chamber 11 through a pipeline. The steam outlet of the plate heat exchanger 21 is connected to the condenser tube 24 and the fresh water collection bottle 26 in sequence. The steam generated in the atomizing heating evaporation chamber 11 is fully condensed into fresh water through the plate heat exchanger 21 and the condenser tube 24.

[0033] In this embodiment, the condenser tube 24 is placed in the condenser box 25, and seawater is used as the heat exchange medium in both the condenser box 25 and the plate heat exchanger 21. The seawater is pumped into the condenser box 25, which is connected to the plate heat exchanger 21 and the water storage heating tank 5 in sequence through pipelines. The condenser box 25 and the plate heat exchanger 21 can be used to preheat the seawater in multiple stages, making full use of the waste heat of the steam.

[0034] The re-evaporation system includes a low-concentration brine collection tank 13 and a high-concentration brine collection tank 16. The low-concentration brine collection tank 13 is connected to the bottom of the atomizing heating evaporation chamber 11 and is used to receive the low-concentration brine produced by the atomizing heating evaporation chamber 11. The low-concentration brine collection tank 13 is also connected to the atomizing evaporation system to input the low-concentration brine into the atomizing evaporation system for secondary evaporation. The high-concentration brine collection tank 16 is used to collect the high-concentration brine produced after secondary evaporation.

[0035] In this embodiment, a pressure relief valve 12 is provided at the connection between the atomizing heating evaporation chamber 11 and the low-concentration brine collection tank 13. When the brine in the evaporation heating chamber reaches a certain amount, the pressure relief valve 12 will reach the preset pressure and discharge the brine into the low-concentration brine collection tank 13 in a timely manner. At the same time, the pressure relief valve 12 can prevent steam from entering the low-concentration brine collection tank 13.

[0036] More specifically, the energy storage battery 4 is connected to the injection pump 19, the high-voltage electrostatic generator 7, the air pump 20, the water storage heating box 5 of the atomizing evaporation system, and the heater in the atomizing heating evaporation chamber 11. When the energy storage battery 4 has sufficient power, it provides power to these devices, and the system starts to operate. At the same time, the photovoltaic energy storage system can also provide power to other devices for lighting, etc.

[0037] More specifically, the inlet and outlet of the condenser 25 are equipped with filter screens. Before the seawater enters the condenser 25, large particulate impurities are filtered out to meet the basic requirements of seawater distillation and desalination.

[0038] More specifically, the outer walls of both the water storage heating box 5 and the atomizing heating evaporation chamber 11 need to be covered with an insulating layer to reduce heat loss.

[0039] More specifically, the heat exchange and condensation system also includes a constriction 9 and a waterproof and breathable membrane 10 at the inlet of the constriction 9. The constriction 9 is located inside the upper right of the atomizing heating evaporation chamber 11 and is connected to the steam inlet of the plate heat exchanger 21 through a pipe and an air pump 20 to promptly remove the steam in the atomizing heating evaporation chamber 11. At the same time, the waterproof and breathable membrane 10 can separate the steam from the atomized droplets and prevent the atomized droplets from entering the heat exchange and condensation system.

[0040] More specifically, the condenser tube 24 adopts a combination of U-shaped and Z-shaped structures. This condensation structure can improve the condensation efficiency of steam and prevent gas backflow. The outlet of the condenser tube is connected to the fresh water collection bottle 26 to collect the fresh water condensed from the steam.

[0041] The re-evaporation system also includes a pressure sensor 14 and a proportional valve 15. The pressure sensor 14 is located at the bottom of the low-concentration brine collection tank 13. When there is enough brine in the low-concentration brine collection tank 13, the pressure sensor 14 will reach a preset pressure, controlling the first execution valve 22 to open and the second execution valve 23 to close. The injection pump 19 injects the brine from the low-concentration brine collection tank into the atomizing evaporation system for secondary desalination. The generated steam will pass through the heat exchange and condensation system again and finally be collected in a freshwater collection bottle. The re-concentrated brine will be collected back into the low-concentration brine collection tank 13, and the seawater concentration in the low-concentration brine collection tank 13 will gradually increase. The proportional valve 15 is located at the connection between the low-concentration brine collection tank 13 and the high-concentration brine collection tank 16. When the brine in the low-concentration brine collection tank 13 is concentrated to the preset concentration of the proportional valve 15, the proportional valve 15 opens, allowing the more concentrated brine to enter the high-concentration brine collection tank 16.

[0042] The high-concentration brine collection tank 16 has an interface 18 on the lower left side, and a valve 17 at the interface. Opening the valve 17 allows highly concentrated seawater to be collected through the interface 18, which can be used as a chemical raw material for further extraction and purification of sea salt.

[0043] The solar-powered seawater desalination cogeneration system provided in this embodiment integrates a photovoltaic energy storage system, an atomizing evaporation system, a heat exchange and condensation system, and a re-evaporation system. The photovoltaic energy storage system absorbs and stores solar energy to provide energy for the entire system operation and other electrical equipment, achieving environmental protection and zero carbon emissions. The atomizing evaporation system heats the seawater before electrostatic atomization, breaking the heated seawater into droplets with micron or even nanometer-sized inner diameters, greatly increasing the evaporation surface. At the same time, under the action of the electric field generated by the ring electrode, the evaporation rate of the seawater is greatly improved. The heat exchange and condensation system absorbs the steam in a timely manner, making full use of the huge latent heat of the steam and condensing it into fresh water for collection, making full use of waste heat and reducing electricity consumption. The re-evaporation system can re-evaporate the evaporated seawater to obtain brine with higher concentration, which can be used to extract chemical raw materials. Moreover, compared with traditional seawater desalination technology, this system improves energy utilization and economic benefits.

[0044] like Figure 3The process of seawater desalination co-production in the aforementioned solar-powered seawater desalination system is as follows: A photovoltaic energy storage system, an atomizing evaporation system, a heat exchange and condensation system, and a re-evaporation system are integrated together. The photovoltaic energy storage system absorbs and stores solar energy to provide energy for the entire system operation and other electrical equipment. The atomizing evaporation system uses the electrical energy from the energy storage battery 4 to heat the seawater, then electrostatically atomize it, and finally evaporate it. The heat exchange and condensation system promptly extracts the steam generated by the atomizing evaporation system, performs heat exchange and condensation, and finally collects the condensed freshwater. The re-evaporation system collects the brine generated by the atomizing evaporation system and re-enters the atomizing evaporation system, subsequently obtaining brine with a higher concentration.

[0045] The solar-powered seawater desalination cogeneration system and photovoltaic energy storage system in this application maximize the amount of sunlight received by the photovoltaic panels, thereby improving power generation efficiency and providing energy for the operation of the entire system and other electrical equipment. This achieves environmental protection, zero carbon emissions, and good economic benefits.

[0046] The solar-powered seawater desalination cogeneration system in this application uses an atomization evaporation system that first heats the seawater and then electrostatically atomizes it, breaking the heated seawater into droplets with micron or even nanometer-sized inner diameters. This significantly increases the evaporation surface area, and under the influence of the electric field generated by the ring electrode, it greatly enhances the evaporation rate of the seawater.

[0047] The solar-powered seawater desalination cogeneration system and operation method described in this application ensure the supply of freshwater while making full use of waste heat and reducing electricity consumption.

[0048] The solar-powered seawater desalination co-production system described in this application produces brine with higher concentration, which can be used to extract chemical raw materials, reducing environmental impact and improving economic efficiency.

[0049] The above embodiments are only used to illustrate the design concept and features of the present invention, and their purpose is to enable those skilled in the art to understand the content of the present invention and implement it accordingly. The protection scope of the present invention is not limited to the above embodiments. Therefore, all equivalent changes or modifications made based on the principles and design ideas disclosed in the present invention are within the protection scope of the present invention.

Claims

1. A solar-powered seawater desalination co-production system, characterized in that, include: Photovoltaic energy storage system, atomizing evaporation system, heat exchange and condensation system, and re-evaporation system; The atomizing evaporation system includes a water storage heating tank (5), an atomizing heating evaporation chamber (11), and an electrostatic atomizing unit. The water storage heating tank (5) heats the input seawater. The electrostatic atomizing unit is located between the water storage heating tank (5) and the atomizing heating evaporation chamber (11). The electrostatic atomizing unit breaks the heated seawater in the water storage heating tank (5) into droplets with micron or even nanometer inner diameters and sprays them into the atomizing heating evaporation chamber (11). Water vapor and low-concentration brine are obtained by evaporation in the atomizing heating evaporation chamber (11). The heat exchange and condensation system condenses the water vapor generated by the atomizing evaporation system into fresh water. The re-evaporation system inputs low-concentration brine into the atomizing evaporation system for re-evaporation to obtain high-concentration brine. The photovoltaic energy storage system converts solar energy into electrical energy and supplies power to the electrical equipment in the atomization evaporation system, heat exchange condensation system, and re-evaporation system. The heat exchange and condensation system includes a heat exchanger, a condenser tube (24), and a fresh water collection bottle (26); the steam inlet of the heat exchanger is connected to the atomizing heating evaporation chamber (11) through a pipeline, and the steam outlet of the heat exchanger is connected to the condenser tube (24) and the fresh water collection bottle (26) in sequence; the condenser tube (24) is placed in the condensation box (25); The condenser (25) is connected to the heat exchanger and the water storage heating tank (5) in sequence through pipelines. Seawater is used as the heat exchange medium in both the condenser (25) and the heat exchanger. After multi-stage preheating of the seawater in the condenser (25) and the heat exchanger, it is input into the water storage heating tank (5). The re-evaporation system includes a low-concentration brine collection tank (13) and a high-concentration brine collection tank (16). The low-concentration brine collection tank (13) is connected to the bottom of the atomizing heating evaporation chamber (11) and is used to receive the low-concentration brine generated by the atomizing heating evaporation chamber (11). The low-concentration brine collection tank (13) is also connected to the atomizing evaporation system to input the low-concentration brine into the atomizing evaporation system for secondary evaporation. The high-concentration brine collection tank (16) is used to collect the high-concentration brine generated after secondary evaporation. The atomizing heating evaporation chamber (11) is provided with a constriction (9). A waterproof and breathable membrane (10) is provided on one side of the constriction (9), and the other side is connected to the heat exchange and condensation system. The steam and atomized droplets are separated by the waterproof and breathable membrane (10) and then fed into the heat exchange and condensation system.

2. The solar-powered seawater desalination co-production system according to claim 1, characterized in that, The electrostatic atomization unit includes a high-voltage electrostatic generator (7), an annular electrode (6), and a nozzle (8); the annular electrode (6) is connected to the high-voltage electrostatic generator (7) to form a high-voltage electric field around the annular electrode (6); the nozzle (8) is located at the center of the annular electrode (6); the inlet end of the nozzle (8) is connected to the water storage heating tank (5), and the outlet end of the nozzle (8) faces into the atomization heating evaporation chamber (11).

3. The solar-powered seawater desalination co-production system according to claim 1, characterized in that, The photovoltaic energy storage system includes a solar panel (1) and an energy storage battery (4). The solar panel (1) converts solar energy into electrical energy and is connected to the energy storage battery (4) through wires. The converted electrical energy can be stored and the energy storage battery (4) can supply power to the electrical equipment in the system.

4. The solar-powered seawater desalination co-production system according to claim 1, characterized in that, The photovoltaic energy storage system is equipped with an orientation adjustment system to adjust the orientation of the solar panel (1).

5. A solar-powered seawater desalination co-production system according to claim 1, characterized in that, The condenser (25) is equipped with filters at both the seawater inlet and outlet.

6. The solar-powered seawater desalination co-production system according to claim 1, characterized in that, The outer walls of the water storage heating box (5) and the atomizing evaporation chamber (11) are both covered with an insulating layer.

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