Low-grade heat energy recovery and storage device and working method thereof

Abstract

The invention relates to the field of low-grade heat energy recovery, and discloses a low-grade heat energy recovery and energy storage device and a working method thereof. A low-grade heat energy recovery and storage device comprises a heat collector, an evaporation chamber, a turbine, a generator, a spraying device and a vacuum pump. After the heat collector absorbs a low-grade heat source, heat is transferred to water in the heat collector, the water is boiled into water vapor, the water vapor drives the turbine to drive the generator to generate electricity, and the water vapor after acting enters the spraying device. The device can effectively overcome the defects in the heat energy recovery technology, the heat energy utilization efficiency is improved, the maintenance cost is reduced, the heat source application range is widened, and a new technical approach is provided for comprehensive utilization of a low-grade energy heat source.

Description

Technical Field

[0001] The present application belongs to the field of low-grade thermal energy recovery, and in particular relates to a low-grade thermal energy recovery and storage device and a working method thereof. Background Art

[0002] Low-grade thermal energy such as geothermal energy (the temperature of rock and soil in underground mines generally increases with depth, shallow mines are about the surface temperature, deep mines can be as high as 60-80°C or above), industrial waste heat (low-grade waste heat generated during industrial production, such as waste heat from the steel, chemical, electric power and other industries), building waste heat, data center waste heat, wastewater thermal energy, environmental thermal energy (heat energy stored in air, water and soil), etc. The utilization of low-grade waste heat is a means of cascading energy utilization and achieving overall energy efficiency improvement.

[0003] With technological advancement, making full use of low-carbon energy such as low-grade industrial waste heat to supply low-grade thermal demand has become a necessary path for energy conservation and carbon reduction, and will also become an important breakthrough for my country to achieve carbon peak and carbon neutrality goals.

[0004] However, the existing low-grade heat recovery technology has at least the following shortcomings:

[0005] (1) Low utilization rate of low-grade thermal energy: Traditional thermal energy utilization devices have low utilization rate of low-grade thermal energy, resulting in a large amount of low-grade thermal energy being wasted;

[0006] (2) Complex system integration: Existing heat recovery and storage systems often require multiple independent devices, which are complex to integrate and have high maintenance costs.

[0007] (3) Low system reliability: Traditional heat recovery and storage systems have low reliability and are prone to failure, which affects the stable operation of the system.

[0008] (4) High cost: The existing heat recovery and storage systems are relatively expensive, which limits their large-scale application.

[0009] Therefore, there is an urgent need to provide a low-grade thermal energy recovery and storage device that can overcome the above-mentioned defects.

[0010] The information in this background technology section is only intended to enhance the understanding of the overall background of the application and should not be construed as an admission or any form of suggestion that the information constitutes the prior art already known to a person of ordinary skill in the art. Summary of the invention

[0011] In order to solve the above problems, the present application provides a low-grade thermal energy recovery and storage device and a working method thereof, which can effectively overcome the shortcomings of thermal energy recovery technology, improve thermal energy utilization efficiency, reduce maintenance costs, broaden the scope of application of heat sources, and provide a new technical approach for the comprehensive utilization of low-grade energy sources.

[0012] In some embodiments of the present application, a low-grade thermal energy recovery and storage device is provided, comprising:

[0013] The heat collector includes a heat collecting tube array, which absorbs low-grade heat sources and transfers heat to water in the heat collecting tube array. The heat collector is in a vacuum environment, and the water absorbs heat and boils to generate water vapor.

[0014] An evaporation chamber is located on the upper part of the heat collector and is sealed and connected to the heat collector;

[0015] A turbine, wherein the turbine is connected to the evaporation chamber through a steam pipe, and the steam pipe is provided with a first one-way valve, which allows the water vapor flowing out of the evaporation chamber to flow to the turbine in one direction;

[0016] The generator is connected to the turbine. The steam passing through the turbine drives the blades in the turbine to produce rotational motion, converting the kinetic energy of the steam into rotational mechanical energy. The rotational mechanical energy generated by the turbine is used to drive the generator to generate electricity.

[0017] A spray device is connected to the upper end of the evaporation chamber. The spray device is also connected to the turbine through a condensate return pipe. The water vapor flowing out of the turbine is condensed into water through the condensate return pipe, and the condensed water is returned to the spray device.

[0018] The vacuum pump is connected to the evaporation chamber through a vacuum pipe, and is used to form a vacuum environment in the space formed by the collector and the evaporator. A second one-way valve is provided on the vacuum pipe to prevent external air from flowing back into the collector and the steam chamber.

[0019] In some embodiments of the present application, the internal structure of the collector is a plurality of branches radiating outward from the center of the collector; each branch contains two cylindrical heat collecting tubes with different diameters, forming a heat collecting tube array, and the cylindrical heat collecting tubes radiate outward from the center of the circle, and the diameter of the cylinder increases from small to large, so that the condensed water can be distributed to each heat collecting tube along the gaps created by the radius difference of the wall.

[0020] In some embodiments of the present application, the two cylindrical heat collecting tubes on each branch have different diameters, and an inclined groove is opened near the center of the circle. The groove is located higher near the center of the circle, allowing water to flow into the cylinder outside the circumference.

[0021] In some embodiments of the present application, the cylindrical heat collecting tubes in the heat collecting tube array are inserted into the low-temperature heat source. If it is a liquid, it is in direct contact; if it is a solid heat source, a heat conductive medium is added at the contact position between the heat collecting tube array and the solid to reduce the thermal resistance during the heat transfer process.

[0022] In some embodiments of the present application, the collector and the steam chamber are both installed with fixing / hanging earrings for fixing and hanging the collector tube and the steam chamber.

[0023] In some embodiments of the present application, a sealing gasket with matching size is placed between the collector and the steam chamber for sealing.

[0024] In some embodiments of the present application, a nozzle interface is provided on the upper part of the steam chamber, which is connected to the spray device; an exhaust interface is provided on the side of the steam chamber, which is connected to the steam pipe; the side of the steam chamber is also connected to the vacuum pipe; the space in the steam chamber and the space in the collector form a closed space for forming water vapor with a preset pressure.

[0025] In some embodiments of the present application, the outer periphery of the steam pipe between the steam chamber and the first one-way valve is also wrapped with thermal insulation cotton to prevent water vapor from condensing when encountering a low-temperature pipe wall, which would turn the gas in the steam pipe into liquid and reduce the amount of steam in the gas.

[0026] In some embodiments of the present application, a spray device is connected to the steam chamber for providing spray water; the spray device includes a water tank, an opening provided in the bottom wall of the water tank at the bottom of the water tank, an iron core sealing the opening, a reset spring provided on the outer periphery of the upper part of the iron core, a nozzle located at the lower part of the iron core, and an electromagnetic coil provided on the outer periphery of the lower part of the iron core; when the relay is energized, the internal electromagnetic coil will generate a magnetic field force, and the magnetic field force will overcome the elastic force of the reset spring to drive the iron core to move upward, thereby generating a gap between the nozzle and the iron core, so that the water in the water tank flows into the steam chamber; when the relay is not energized, the iron core is pressed tightly by the reset spring, so that the conical structure at the lower part of the iron core is tightly combined with the nozzle, and water cannot flow into the steam chamber.

[0027] In some embodiments of the present application, when the relay is energized, the water in the water tank passes through the bottom wall of the water tank in sequence, the gap between the iron core and the bottom wall of the water tank, the gap between the iron core and the electromagnetic coil, the circumferential annular water groove opened at the conical position of the iron core head, and the nozzle, ultimately realizing the water supply.

[0028] In some embodiments of the present application, a water source is stored inside the spray device; the water source comes from two parts: one part is the condensate in the condensate return pipe that flows back to the spray device; the other part is an external water source.

[0029] In some embodiments of the present application, the spray device is covered by a semi-sealed cover, connected to the external environment, and can filter tiny particles in the external environment; the external water source can be replenished by opening the semi-sealed cover.

[0030] In some embodiments of the present application, the low-grade thermal energy recovery and storage device also includes a battery for storing electrical energy of the generator.

[0031] In some embodiments of the present application, the low-grade thermal energy recovery and storage device also includes a power control and driver, which is electrically connected to the battery, and the battery can provide electrical energy to the power control and driver.

[0032] In some embodiments of the present application, the surplus electric energy of the generator is also used to be integrated into the power grid.

[0033] In some embodiments of the present application, the low-grade thermal energy recovery and storage device also includes a relay, which is connected to the spray device and is used to control the opening and closing of the spray device; the relay is electrically connected to the generator to provide the electrical energy required by the relay.

[0034] In some embodiments of the present application, a working method of a low-grade heat energy recovery and storage device is also provided, specifically, firstly, after the heat collector absorbs the low-grade heat source through the heat collecting tube array, the heat is transferred to the water inside the heat collecting tube array to become water vapor, and the vacuum degree in the heat collecting tube is controlled by a vacuum pump;

[0035] The water vapor runs in the steam pipe and flows to the turbine in one direction through the first check valve to prevent the water vapor from circulating;

[0036] The steam drives the blades in the turbine to produce rotational motion. The rotational mechanical energy generated by the turbine is used to drive the generator to generate electricity; the generated electrical energy is stored in the battery, or provided to the power supply control and drive.

[0037] The power control and driver provide power to the vacuum pump and relay respectively, thus generating corresponding actions;

[0038] After the water vapor flows into the turbine, the water vapor after doing work is condensed into water through the condensate return pipe, and the condensed water flows back to the spray device.

[0039] In some embodiments of the present application, the relay drives the iron core in the spray device to move after being energized, thereby turning on the spray device to spray water. When the relay is de-energized, the return spring in the spray wheel device restores the iron core to its initial state through the pre-tightening spring force, thereby stopping the water spray.

[0040] In some embodiments of the present application, the vacuum pump and the spray device do not work at the same time. Specifically, when the vacuum pump is working, it starts to suck the vacuum in the collector and the steam chamber. At this time, the spray device does not work to prevent the vacuum pump from pumping out water and failing to effectively form a certain vacuum degree. When the spray device is working, that is, spraying water, the vacuum pump does not work to prevent the water sprayed into the collector and the steam chamber from being pumped away.

[0041] In some embodiments of the present application, redundant design and fault self-diagnosis function are adopted to improve the reliability of the system.

[0042] Compared with the prior art, this application has at least the following advantages:

[0043] 1. This application overcomes the defect of low utilization efficiency of low-temperature heat sources in heat recovery technology: this application adopts a vacuum environment to lower the boiling point of water, thereby improving the heat energy absorption capacity of the low-temperature heat source. This application adopts a spray collector to increase the contact area between the heat source water and the collector tube, thereby improving the heat exchange efficiency.

[0044] 2. This application adopts a modular design, dividing the system into a collector module, a turbine power generation module, a battery module and a control module, etc., which is easy to install, maintain and expand, and improves the integration and flexibility of the system.

[0045] 3. This application uses a spraying method to transport heat source water to the collector, which avoids the deposition of impurities in the heat source water on the collector tube and reduces the requirements for the quality of the heat source water. This application reduces the consumption of water resources and solves the problem of high water resource consumption in traditional thermal energy management technology.

[0046] 4. This application uses low-grade heat sources and does not require the consumption of fossil fuels. It is a sustainable energy solution with multiple uses. The electricity generated can be used for power generation, energy storage or grid connection. It is energy-saving and environmentally friendly, reducing energy waste and environmental pollution.

[0047] 5. This application can utilize low-grade heat sources of solid, liquid or gas, such as geothermal rock, industrial wastewater, industrial waste gas, etc., broadening the scope of heat energy sources.

[0048] 6. This application reduces the boiling point of water by evacuating the collector, allowing water to boil and evaporate at a lower temperature, thereby absorbing a large amount of low-grade heat; using water vapor to drive the turbine to generate electricity, converting thermal energy into electrical energy and storing it in the battery. Spraying device recycling: Condensed water flows back to the spraying device and is supplemented with external water sources to form a recycled water source, reducing the consumption of water resources. Vacuum and spray control: By controlling the working sequence of the vacuum pump and the spraying device, the vacuum pump is prevented from drawing away the sprayed water, ensuring the stable operation of the system.

[0049] 7. This application prevents the vacuum pump from sucking away the sprayed water by controlling the working sequence of the vacuum pump and the spray device, thereby ensuring stable operation of the system and solving the problem of system instability in traditional thermal energy management technology.

[0050] 8. Multi-energy complementarity: This application can be used in conjunction with other renewable energy systems, such as photovoltaic systems, wind power generation systems, etc., to form a multi-energy complementary integrated system, which improves the comprehensive utilization efficiency and reliability of the system. Intelligent control: This application adopts an intelligent control system to monitor and control each module of the system in real time, optimize system operating parameters, and improve the overall performance and stability of the system. Reduce system costs. This application adopts redundant design and fault self-diagnosis function to improve the reliability of the system and ensure stable operation of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] The drawings in the specification, which constitute a part of the present application, are used to provide further understanding of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute improper limitations on the present application.

[0052] Figure 1 This is a schematic diagram of the structure of a low-grade thermal energy recovery and storage device in some embodiments of the present application;

[0053] Figure 2 It is a schematic diagram of the three-dimensional structure of the heat collection chamber in some embodiments of the present application;

[0054] Figure 3 A top view of a heat collection chamber in some embodiments of the present application;

[0055] Figure 4 AA cross-sectional view of the heat collection chamber in some embodiments of the present application;

[0056] Figure 5 Schematic diagram of the three-dimensional structure of the steam chamber in some embodiments of the present application;

[0057] Figure 6 A front view of a steam chamber in some embodiments of the present application;

[0058] Figure 7 It is a left view of the steam chamber in the BB direction in some embodiments of the present application;

[0059] Figure 8 It is a schematic diagram of the structure of the spray device in some embodiments of the present application;

[0060] Fig. 9 This is a timing diagram of the operation of the vacuum pump and the spray device in some embodiments of the present application.

[0061] Among them, 1: collector; 2: steam chamber; 3: insulation cotton; 4: first one-way valve; 5: steam pipe; 6: turbine; 7: generator; 8: battery; 9: power control and driver; 10: wire; 11: vacuum pump; 12: second one-way valve; 13: spray device; 14: semi-sealed cover; 15: condensate return pipe; 16: relay; 17: collector tube array; 18: water source distribution chamber; 19: fixing and lifting earrings; 20: nozzle interface; 21: exhaust interface; 22: vacuum pump interface; 23: water tank; 24: bottom wall of water tank; 25: seal; 26: reset spring; 27: iron core; 28: water tank; 29: nozzle; 30: electromagnetic coil; 31: steam chamber wall. DETAILED DESCRIPTION

[0062] Below, the specific embodiments of the present application are described in detail in conjunction with the accompanying drawings, but they are not intended to limit the present application. In order to enable those skilled in the art to better understand the technical solution of the present disclosure, the present disclosure is described in detail below in conjunction with the accompanying drawings and specific implementation methods. Below, the embodiments of the present disclosure are further described in detail in conjunction with the accompanying drawings and specific embodiments, but they are not intended to limit the present disclosure.

[0063] All terms (including technical terms or scientific terms) used in the present disclosure have the same meanings as those understood by ordinary technicians in the field to which the present disclosure belongs, unless otherwise specifically defined. It should also be understood that terms defined in general dictionaries, such as general dictionaries, should be interpreted as having meanings consistent with their meanings in the context of the relevant technology, and should not be interpreted in an idealized or extremely formal sense, unless explicitly defined herein.

[0064] Technologies, methods, and equipment known to ordinary technicians in the relevant art may not be discussed in detail, but where appropriate, the technologies, methods, and equipment should be considered as part of the specification.

[0065] The following is combined with Figure 1-9 The technical solution of this application is described in detail.

[0066] [Low-grade thermal energy recovery and storage device]

[0067] In some embodiments of the present application, Figure 1 As shown, the low-grade heat energy recovery and storage device comprises a collector 1, a steam chamber 2, a first one-way valve 4, a steam pipe 5, a second one-way valve 12, and a spray device 13 to form a closed space; Figure 1 The solid arrows represent the flow direction of water vapor, and the dotted arrows represent the flow direction of current.

[0068] In some embodiments of the present application, the collector 1 is Figure 2After the heat collecting tube array 17 in the heat collecting tube array 17 absorbs the low-grade heat source, the heat is transferred to the water inside the heat collecting tube array 17; since the inside of the heat collector 1 is a vacuum environment, the water can boil at a relatively low temperature to generate water vapor.

[0069] In some embodiments of the present application, water vapor runs in the steam pipe 5 and drives the turbine 6 through the first one-way valve 4 (the flow direction of the water vapor in the one-way valve is one-way flow from the space formed by the collector 1 and the steam chamber 2 to the turbine 6, preventing the water vapor from looping).

[0070] In some embodiments of the present application, the outside of the steam pipe 5 is wrapped with thermal insulation cotton to prevent water vapor from condensing when encountering a low-temperature pipe wall. This phenomenon will turn the gas in the steam pipe 5 into liquid and reduce the amount of steam in the gas.

[0071] In some embodiments of the present application, the water vapor drives the blades in the turbine 6 to generate a rotational motion, thereby converting the kinetic energy of the water vapor into rotational mechanical energy. Figure 1 It can be seen that the water vapor flows along the radial direction of the turbine 6, and the power generated is in the axial direction perpendicular to the radial direction. The rotational mechanical energy generated by the turbine 6 is used to drive the generator 7 to generate electricity, and the generated electric energy is stored in the battery 8, or provides electric energy to the power control and driver 9.

[0072] In some embodiments of the present application, the electric energy is transmitted through the wire 10. The power control and driver 9 respectively provides electric energy to the vacuum pump 11 and the relay 16, thereby generating corresponding actions.

[0073] In some embodiments of the present application, after the water vapor flows into the turbine 6, the water vapor after doing work is condensed into water through the condensate return pipe 15 (the wall surface of the condensate return pipe 15 is not wrapped with thermal insulation cotton, so it is easier to generate condensed water), and the condensed water is returned to the spray device 13;

[0074] In some embodiments of the present application, the spray device 13 is as follows: Figure 8 As shown: the vacuum pump 11 is connected to the second one-way valve 12 (the flow direction of the second one-way valve 12 is from the space formed by the collector 1 and the steam chamber 2 to the vacuum pump 11), and the one-way connection prevents external air from flowing back into the collector 1 and the steam chamber 2.

[0075] In some embodiments of the present application, the working principle of the relay 16 is as follows: Figure 8 As shown, the main function is that when the relay 16 is energized, it will drive the iron core 27 in the spray device 13 to move, thereby turning on the spray device 13 to spray water; when the relay 16 is de-energized, the reset spring 26 in the spray device 13 restores the iron core 27 to its initial state through the pre-tightening spring force, thereby stopping the water spray.

[0076] In some embodiments of the present application, a water source is stored inside the spray device 13. The water source comes from two parts: condensate in the condensate return pipe 15 flows back to the spray device 13; and an external water source.

[0077] In some embodiments of the present application, the spray device 13 is covered by a semi-sealed cover 14 , connected to the external environment, and can filter tiny particles in the external environment; the external water source can be replenished by opening the semi-sealed cover 14 .

[0078] In some embodiments of the present application, the electric energy generated by the generator 7 is provided to the battery 8 for storage on the one hand, and on the other hand, provides electric energy to the vacuum pump 11 and the relay 16. If there is excess electric energy that cannot be stored by the battery 88, the excess electric energy can be connected in parallel with the power grid to provide electric energy to the outside.

[0079] [Collector 1 and heat collection principle]

[0080] The collector 1 is used to absorb low-temperature heat sources such as solid, liquid or gas, such as geothermal rock in mines and geothermal soil in residential areas; liquid such as industrial waste water; and gas such as industrial waste gas, water vapor, etc.

[0081] The collector 1 is placed at the above-mentioned low-temperature heat source, and the phase change principle is used to evaporate and absorb heat; because the boiling point of water under 1 atmosphere is 100°C, this limits the boiling phase change ability of water at low heat sources. However, after a certain degree of vacuum is drawn in the collector 1, the internal space of the collector 1 is negative pressure, which can reduce the boiling point of water, thereby absorbing a large amount of heat through phase change. The negative pressure in the collector 1 is provided by the vacuum pump 11. The heat source transfers heat to the heat collecting tube array 17 in the collector 1, so that the water in the collector 1 boils and evaporates, generating driving force.

[0082] like Figure 1-4 As shown, a certain space is formed between the collector 1 and the steam chamber 2, and then a closed space is formed by the first one-way valve 4, the second one-way valve 12 and the spray device 13; the internal structure of the collector 1 is a plurality of branches (for example, it can be set to 8) radiating outward from the center of the cylinder to form a water source distribution chamber 18.

[0083] Each branch contains two cylindrical heat collecting tubes with different diameters. The diameter of the cylinder increases from small to large in the radial direction from the center of the circle. This is mainly because the condensed water needs to be distributed to each heat collecting tube along the gaps created by the radius difference of the wall. Figure 4 As shown, the two cylindrical collector tubes on each branch have different diameters, and an inclined "groove" is opened near the center of the circle. The groove is located higher near the center of the circle, which is conducive to the flow of water into the large cylinder outside the circumference.

[0084] The heat collecting tubes in the heat collecting tube array 17 are thin-walled tubes. When the heat collecting tubes are inserted into the low-temperature heat source, if it is a liquid, they are in direct contact. If it is a solid heat source, a heat conducting medium is added at the contact position between the heat collecting tube array 17 and the solid to reduce the thermal resistance during the heat transfer process.

[0085] Both the collector 1 and the steam chamber 2 are equipped with fixing / lifting earrings for fixing and lifting these two components.

[0086] For sealing, a sealing gasket with matching size is placed between the collector 1 and the steam chamber 2. [Steam Chamber 2 and Steam Power Driving Principle]

[0087] like Figure 5-7 As shown, the nozzle interface 20 on the top of the steam chamber 2 is connected to the spray device 13; the exhaust interface 21 on the side of the steam chamber 2 is connected to the steam pipe 5; the other side is connected to the vacuum pipe through the vacuum pump interface 22; the space in the steam chamber 2 and the space in the collector 1 form a closed space for forming water vapor with a certain pressure.

[0088] [Spraying device 13 and spraying principle]

[0089] The spray device 13 is connected to the steam chamber 2 and is used to provide spray water. Figure 8 As shown, the spray device 13 includes: a water tank 23, a spray head 29, an electromagnetic coil 30, an iron core 27, a return spring 26, etc.

[0090] The water tank 23 includes a water tank bottom wall 24 , which is provided with an opening, and the iron core blocks the opening; the water tank bottom wall 24 and the spray device wall are sealed by a seal 25 ; the spray head is located at the lower part of the steam chamber wall 31 .

[0091] When the wire 10 in the relay 16 is energized, the internal electromagnetic coil 30 generates a magnetic field force. The electromagnetic coil 30 is a waterproof electromagnetic coil. The magnetic field force overcomes the elastic force of the reset spring 26 to drive the iron core 27 to move upward, thereby generating a gap between the nozzle and the iron core 27, so that the water in the water tank 23 flows smoothly into the steam chamber 2. When the relay 16 is not energized, the iron core 27 is pressed by the reset spring 26, so that the conical structure at the bottom of the iron core 27 is tightly combined with the nozzle, and the water cannot flow into the steam chamber 2. When the relay 16 is energized, the water in the water tank 23 passes through the wall of the water tank 23 (there is a gap between the iron core 27 and the wall of the water tank 23), the gap between the iron core 27 and the "waterproof battery coil", the circumferential annular water tank 28 opened at the cone position of the head of the iron core 27, and the nozzle, and finally realizes the supply of water.

[0092] [Vacuum and spray control principle]

[0093] The vacuum pump 11 and the spray device 13 cannot work at the same time; when the vacuum pump 11 works, it starts to draw vacuum from the collector 1 and the steam chamber 2. At this time, the spray device 13 cannot work to prevent the vacuum pump 11 from drawing out water and failing to effectively form a certain vacuum degree. When the spray device 13 works, that is, sprays water, the vacuum pump 11 cannot work to prevent the water sprayed into the collector 1 and the steam chamber 2 from being drawn out.

[0094] The spray device 13 sprays water while evaporating to form water vapor, thereby driving the turbine 6 to form a one-way air or water vapor flow path under the joint action of the first one-way valve 4 and the second one-way valve 12. Fig. 9 As shown in the figure, the vacuum pump 11 and the spray device 13 work timing diagram, where uTrue and uSpray are the voltages passing through the vacuum pump 11 and the relay 16 respectively. It can be seen from the figure that 0-t 1 ,t 1 -t 2、 t 2 -t 3、 t 3 -t 4 Both cannot be powered on at the same time.

[0095] In some embodiments of the present application, a low-grade thermal energy recovery and storage device includes a collector module, a turbine 6 power generation module, a battery module and a control module, and the modules are connected by pipelines or wires 10.

[0096] In some embodiments of the present application, the aforementioned collector 1 and steam chamber 2 are integrated into a collector module; the turbine 6 and the generator 7 are integrated into a turbine power generation module; the battery module includes the aforementioned battery 8; the control module includes a power control and driver 9; and the remaining components can be arranged in the same manner as described above.

[0097] [Collector module]

[0098] In addition to vacuum tube collectors, flat plate collectors, parabolic trough collectors or concentrated photovoltaic cogeneration systems can also be used as collectors.

[0099] In addition to glass vacuum tubes, the collector can also be made of metal vacuum tubes, ceramic vacuum tubes or plastic vacuum tubes.

[0100] The collector structure can adopt a single-tube, double-tube or multi-tube collector structure.

[0101] Vacuum degree: The vacuum degree can be adjusted according to the heat source temperature and system requirements.

[0102] [Turbine power generation module]

[0103] Turbine type: In addition to axial flow turbines, radial flow turbines or screw turbines can also be used.

[0104] Turbine material: In addition to stainless steel, high temperature and corrosion resistant materials such as titanium alloy or ceramics can also be used.

[0105] Generator type: In addition to permanent magnet synchronous generators, induction generators or DC generators can also be used.

[0106] [Battery module]

[0107] Battery type: In addition to lead-acid batteries, lithium-ion batteries, flow batteries or flywheel energy storage systems can also be used.

[0108] Battery capacity: The battery capacity can be adjusted according to system requirements and storage time.

[0109] Battery Management System: Different battery management systems can be used to optimize the battery's charge and discharge performance and life.

[0110] [Control module]

[0111] Control Algorithms: Different control algorithms can be used to optimize the operating efficiency and stability of the system.

[0112] Sensor type: Different sensors can be used to monitor system parameters such as temperature, pressure, flow, etc.

[0113] Human-machine interface: Different display screens and control panels can be used to achieve human-machine interaction.

[0114] The low-grade heat energy recovery and storage device of the present application creates a vacuum environment in the collector and the steam chamber, reduces the boiling point of water, and improves the heat energy absorption capacity and heat energy conversion efficiency.

[0115] The steam chamber of the present application is separated from the collector: the steam chamber is separated from the collector, thereby avoiding the influence of bubbles generated in the collector on the steam chamber, and improving the steam quality and the power generation efficiency of the generator.

[0116] The present application adopts an automated control system to control the spray device and the vacuum pump, which simplifies the maintenance process and improves the stability and reliability of the system.

[0117] The present application can be applied to a wide range of low-grade thermal energy absorption. By regulating the vacuum degree formed by the vacuum pump, the boiling point temperature of water can be adjusted, so that energy can be effectively recovered within a larger low-grade temperature range. The device can realize the absorption and recovery of low-grade solid energy (geothermal), liquid energy (wastewater) and air energy (waste gas).

[0118] The part of the present application that needs to consume electric energy is the relay, which consumes very little energy. The vacuum pump 11 works intermittently and only requires relatively low power to generate a large negative pressure. Both consume less electric energy. According to the law of conservation of energy, the temperature absorbed from the heat source will eventually generate excess energy. The vacuum environment reduces the boiling point of water, increases the heat absorption capacity, and thus improves the heat energy conversion efficiency.

[0119] The device of the present application can be adjusted according to actual needs, from a small distributed system to a large centralized system.

[0120] The device of the present application can be integrated in different ways with other renewable energy systems, power grids or heat networks.

[0121] The above are only specific implementations of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A low-grade thermal energy recovery and storage device, characterized in that: include: The heat collector includes a heat collecting tube array, which absorbs low-grade heat sources and transfers heat to water in the heat collecting tube array. The heat collector is in a vacuum environment, and the water absorbs heat and boils to generate water vapor. An evaporation chamber is located on the upper part of the heat collector and is sealed and connected to the heat collector; A turbine, wherein the turbine is connected to the evaporation chamber through a steam pipe, and the steam pipe is provided with a first one-way valve, which allows the water vapor flowing out of the evaporation chamber to flow to the turbine in one direction; The generator is connected to the turbine. The steam passing through the turbine drives the blades in the turbine to produce rotational motion, converting the kinetic energy of the steam into rotational mechanical energy. The rotational mechanical energy generated by the turbine is used to drive the generator to generate electricity. A spray device is connected to the upper end of the evaporation chamber. The spray device is also connected to the turbine through a condensate return pipe. The water vapor flowing out of the turbine is condensed into water through the condensate return pipe, and the condensed water is returned to the spray device. The vacuum pump is connected to the evaporation chamber through a vacuum pipe, and is used to form a vacuum environment in the space formed by the collector and the evaporator. A second one-way valve is provided on the vacuum pipe to prevent external air from flowing back into the collector and the steam chamber.

2. A low-grade thermal energy recovery and storage device according to claim 1, characterized in that: The internal structure of the collector is that multiple branches radiate outward from the center of the collector; each branch contains two cylindrical heat collection tubes with different diameters, forming a heat collection tube array. The cylindrical heat collection tube radiates outward from the center of the circle, and the diameter of the cylinder increases from small to large, so that the condensed water can be distributed to each heat collection tube along the gaps created by the radius difference of the wall.

3. A low-grade thermal energy recovery and storage device according to claim 2, characterized in that: The two cylindrical heat collecting tubes on each branch have different diameters, and an inclined groove is opened near the center of the circle. The groove is located higher near the center of the circle, so that water flows into the cylinder outside the circumference.

4. A low-grade thermal energy recovery and storage device according to claim 1, characterized in that: A nozzle interface is provided on the upper part of the steam chamber, which is connected to the spray device; an exhaust interface is provided on the side of the steam chamber, which is connected to the steam pipe; the side of the steam chamber is also connected to the vacuum pipe; the space in the steam chamber and the space in the collector form a closed space for forming water vapor with a preset pressure; preferably, the collector and the steam chamber are both equipped with fixing / hanging earrings for fixing and hanging the collector pipe and the steam chamber; preferably, for the sake of sealing, a sealing gasket of matching size is placed between the collector and the steam chamber; preferably, the outer periphery of the steam pipe between the steam chamber and the first one-way valve is also wrapped with thermal insulation cotton.

5. A low-grade thermal energy recovery and storage device according to claim 1, characterized in that: The low-grade heat energy recovery and storage device further comprises a relay connected to the spray device for controlling the opening and closing of the spray device; the relay is electrically connected to the generator; The spray device includes a water tank, an opening on the bottom wall of the water tank at the bottom of the water tank, an iron core that blocks the opening, a reset spring arranged on the outer periphery of the upper part of the iron core, a nozzle located at the lower part of the iron core, and an electromagnetic coil arranged on the outer periphery of the lower part of the iron core; when the relay is energized, the internal electromagnetic coil will generate a magnetic field force, and the magnetic field force overcomes the elastic force of the reset spring to drive the iron core to move upward, thereby generating a gap between the nozzle and the iron core, so that the water in the water tank flows into the steam chamber; when the relay is not energized, the iron core is pressed tightly by the reset spring, so that the conical structure at the lower part of the iron core is tightly combined with the nozzle, and water cannot flow into the steam chamber.

6. A low-grade thermal energy recovery and storage device according to claim 1, characterized in that: When the relay is energized, the water in the water tank passes through the bottom wall of the water tank, the gap between the iron core and the bottom wall of the water tank, the gap between the iron core and the electromagnetic coil, the circular annular water groove opened at the cone position of the iron core head, and the nozzle, finally realizing the water supply.

7. A low-grade thermal energy recovery and storage device according to claim 1, characterized in that: A water source is stored inside the spray device; the water source comes from two parts: one part is the condensate in the condensate return pipe that flows back to the spray device; the other part is an external water source; preferably, the spray device is covered by a semi-sealed cover, connected to the external environment, and can filter tiny particles in the external environment; the external water source can be replenished by opening the semi-sealed cover.

8. A low-grade thermal energy recovery and storage device according to claim 1, characterized in that: The low-grade thermal energy recovery and storage device also includes a battery for storing the electrical energy of the generator; And / or the low-grade thermal energy recovery and storage device further comprises a power control and driver, which is electrically connected to the storage battery, and the storage battery can provide electric energy to the power control and driver; And / or the excess electrical energy of the generator can also be used to be connected to the power grid.

9. A working method of a low-grade thermal energy recovery and storage device, characterized in that: A low-grade thermal energy recovery and storage device according to any one of claims 1 to 8 is used, specifically: First, the collector absorbs low-grade heat source through the heat collecting tube array, transfers the heat to the water inside the heat collecting tube array, turns it into water vapor, and controls the vacuum degree inside the heat collecting tube through a vacuum pump; The water vapor runs in the steam pipe and flows to the turbine in one direction through the first check valve to prevent the water vapor from circulating; The steam drives the blades in the turbine to produce rotational motion. The rotational mechanical energy generated by the turbine is used to drive the generator to generate electricity; the generated electrical energy is stored in the battery, or provided to the power control and drive; The power control and driver provide power to the vacuum pump and relay respectively, thus generating corresponding actions; After the water vapor flows into the turbine, the water vapor after doing work is condensed into water through the condensate return pipe, and the condensed water flows back to the spray device.

10. A working method of a low-grade thermal energy recovery and storage device according to claim 9, characterized in that: The vacuum pump and the spray device do not work at the same time. Specifically, when the vacuum pump is working, it starts to draw the vacuum in the collector and the steam chamber. At this time, the spray device does not work to prevent the vacuum pump from pumping out water and failing to effectively form a certain vacuum degree. When the spray device is working, that is, spraying water, the vacuum pump does not work to prevent the water sprayed into the collector and the steam chamber from being pumped away.

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