A waste heat power generation system

Abstract

The present invention relates to the field of power generation technology, and in particular to a waste heat power generation system. The waste heat power generation system includes an integrated heat exchange device, a power generation system and a detection device. The integrated heat exchange device includes a high-pressure evaporator, a low-pressure evaporator and a regenerator, which can vaporize at least one liquid working fluid under the action of waste heat; the power generation system uses the gaseous working fluid to generate electricity; the detection device is arranged on the waste heat inlet opened on the high-pressure evaporator and is electrically connected to the controller, and the detection device includes a temperature sensor and a flow sensor; when the temperature detected by the temperature sensor is higher than the set threshold within a set time period, and the flow detected by the flow sensor is higher than the set threshold within a set time period, the controller controls the waste heat power generation system to switch to a single working fluid power generation mode; otherwise, the controller controls the waste heat power generation system to switch to a dual working fluid power generation mode. With this design, the power generation mode is switched according to the temperature and flow of the waste heat to ensure maximum energy utilization.

Description

Technical Field

[0001] The present invention relates to the technical field of power generation, and in particular to a waste heat power generation system. Background Art

[0002] Recycling waste heat generated during industrial production to generate electricity can effectively alleviate energy shortages and avoid energy waste. Existing waste heat power generation systems use the same power generation method for different heat sources. However, when the temperature and flow rate of waste heat vary widely, the heat from the waste heat cannot be fully utilized. Summary of the Invention

[0003] In order to overcome the problems existing in the related art, the present invention provides a waste heat power generation system to improve the energy utilization rate.

[0004] Some embodiments of the present invention provide a waste heat power generation system, comprising:

[0005] An integrated heat exchange device, comprising a high-pressure evaporator, a low-pressure evaporator, and a regenerator, wherein the high-pressure evaporator is provided with a waste heat inlet, and the integrated heat exchange device is capable of vaporizing at least one liquid working medium under the action of waste heat resources;

[0006] a power generation system connected to the integrated heat exchange device, the power generation system being used to generate electricity using the gaseous working medium;

[0007] a detection device, disposed on the waste heat inlet, the detection device being electrically connected to a controller, the controller being configured to receive a detection result sent by the detection device, the detection device comprising a temperature sensor and a flow sensor;

[0008] When the temperature detected by the temperature sensor is higher than a set threshold within a set time period, and the flow rate detected by the flow sensor is higher than a set threshold within a set time period, the controller controls the integrated heat exchange device and the power generation system to switch to a single-fluid power generation mode; otherwise, the controller controls the integrated heat exchange device and the power generation system to switch to a dual-fluid power generation mode.

[0009] In some embodiments of the present invention, a first pipe and a first space are provided in the high-pressure evaporator, the first pipe contains a first working medium, the first space is not connected to the first pipe, and the waste heat inlet is connected to the first space;

[0010] The low-pressure evaporator is provided with a second pipe and a second space. In the single-working fluid power generation mode, the second pipe contains the first working fluid, and in the dual-working fluid power generation mode, the second pipe contains the second working fluid. The second space is not connected to the second pipe. The first space is connected to the second space, and the first space and the second space are used to accommodate waste heat resources. The boiling point of the first working fluid is higher than that of the second working fluid.

[0011] The regenerator includes a third pipe and a third space, the third pipe and the third space are not connected, the third pipe is connected to the second pipe, and a first valve is provided between the third pipe and the second pipe;

[0012] The power generation system includes a gas-liquid separation device, wherein the feed port of the gas-liquid separation device is connected to the first pipeline, the liquid outlet of the gas-liquid separation device is connected to the second pipeline via a fourth pipeline, the fourth pipeline is provided with a first throttle valve, and the liquid outlet is also connected to the third space via a fifth pipeline, the fifth pipeline is provided with a second valve;

[0013] In the single-fluid power generation mode, the controller controls the first throttle valve to open, the first valve to close, and the second valve to close; in the dual-fluid power generation mode, the controller controls the first valve to open, the second valve to open, and the first throttle valve to close.

[0014] In some embodiments of the present invention, the second pipeline is connected to the working medium storage device via a supplementary pipeline, and a supplementary valve is provided on the supplementary pipeline;

[0015] When the single working fluid power generation mode is switched to the dual working fluid power generation mode, the supplementary valve is opened, and the second working fluid enters the second pipeline from the working fluid storage device; when the dual working fluid power generation mode is switched to the single working fluid power generation mode, the supplementary valve is opened, and the second working fluid is discharged from the second pipeline to the working fluid storage device.

[0016] In some embodiments of the present invention, the power generation system includes a first circuit and a second circuit, wherein:

[0017] The first circuit includes a high-pressure magnetic levitation expander, a condensing device, and a first pump body connected in sequence, the high-pressure magnetic levitation expander is connected to the gas outlet of the gas-liquid separation device, and the first pump body is connected to the first pipeline;

[0018] The second circuit includes a low-pressure magnetic levitation expander, the condensing device, and a second pump body connected in sequence. The low-pressure magnetic levitation expander is communicated with the second pipeline, and the second pump body is connected to the second pipeline.

[0019] In some embodiments of the present invention, the condensing device includes a high-pressure condenser and a low-pressure condenser, and the high-pressure condenser is provided with a first working fluid pipeline and a second working fluid pipeline.

[0020] The first working fluid pipeline is in communication with the high-pressure magnetic levitation expander;

[0021] The low-pressure magnetic levitation expander and the second working medium pipeline are connected via a sixth pipeline, and a third valve is provided on the sixth pipeline;

[0022] The low-pressure magnetic levitation expander and the third working medium pipeline of the low-pressure condenser are connected through a seventh pipeline, and a fourth valve is provided on the seventh pipeline.

[0023] In some embodiments of the present invention, the waste heat power generation system further includes a cooling system, the cooling system including a cooling water generating device, a fifth valve is provided between the first cooling water pipe of the high-pressure condenser and the second cooling water pipe of the low-pressure condenser, and when the fifth valve is opened, the cooling water generating device is connected in series with the first cooling water pipe and the second cooling water pipe;

[0024] The first cooling water pipeline and the cooling water generating device are also connected through an eighth pipeline, and a sixth valve is provided on the eighth pipeline.

[0025] In some embodiments of the present invention, the third valve, the fourth valve, the fifth valve, and the sixth valve are all electrically connected to the controller.

[0026] When in the single working fluid power generation mode, the controller controls the third valve to be open, the fourth valve to be closed, the fifth valve to be closed, and the sixth valve to be open;

[0027] The gaseous first working fluid in the high-pressure magnetic levitation expander is condensed into a liquid state in the first working fluid pipeline of the high-pressure condenser and is transported to the first pipeline by the first pump body; the gaseous first working fluid in the low-pressure magnetic levitation expander is condensed into a liquid state in the second working fluid pipeline of the high-pressure condenser and is transported to the second pipeline by the second pump body; the cooling water generated by the cooling water generating device passes through the first cooling water pipeline and the eighth pipeline in sequence and then flows back to the cooling water generating device.

[0028] In some embodiments of the present invention, when in the dual-fluid power generation mode, the controller controls the third valve to be closed, the fourth valve to be opened, the fifth valve to be opened, and the sixth valve to be closed;

[0029] The first working fluid in the gaseous state in the high-pressure magnetic levitation expander is condensed into a liquid state in the high-pressure condenser and is transported to the first pipeline by the first pump body; the second working fluid in the gaseous state in the low-pressure magnetic levitation expander is condensed into a liquid state in the low-pressure condenser and is transported to the second pipeline by the second pump body; the cooling water generated by the cooling water generating device passes through the first cooling water pipeline and the second cooling water pipeline in sequence and then flows back to the cooling water generating device.

[0030] In some embodiments of the present invention, the third space of the regenerator is connected to the first working medium pipeline through a condensing pipeline, and a second throttle valve is provided on the condensing pipeline, and the second throttle valve is electrically connected to the controller;

[0031] When in the single working fluid power generation mode, the controller controls the second throttle valve to close; when in the dual working fluid power generation mode, the controller controls the second throttle valve to open, and the first working fluid in the third space flows to the high-pressure condenser for condensation.

[0032] In some embodiments of the present invention, a waste heat outlet is further provided on the low-pressure evaporator, and the waste heat outlet is communicated with the second space.

[0033] The technical solutions provided by the embodiments of the present invention may have the following beneficial effects:

[0034] The present invention provides a waste heat power generation system, which reduces the space occupied by the waste heat power generation system by arranging an integrated heat exchange device; by arranging a detection device on the waste heat inlet of the high-pressure evaporator, when the temperature and flow of the heat source detected by the temperature sensor and the flow sensor are in a high and stable state, the waste heat power generation system switches to a single working fluid power generation mode, which can ensure higher power generation efficiency and energy utilization efficiency; otherwise, the waste heat power generation system switches to a dual working fluid power generation mode, which can ensure higher net output power, utilize the heat of waste heat resources in a step-by-step manner, and improve the utilization rate of the heat source, thereby ensuring maximum power generation efficiency.

[0035] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0037] Figure 1 is a structural schematic diagram of a waste heat power generation system according to an exemplary embodiment;

[0038] Figure 2is a schematic structural diagram of an integrated heat exchange device according to an exemplary embodiment;

[0039] Figure 3 is a schematic diagram showing the flow direction of the working fluid and cooling water when the waste heat power generation system is in a single working fluid power generation mode according to an exemplary embodiment;

[0040] Figure 4 It is a schematic diagram showing the flow direction of the working fluid and cooling water when the waste heat power generation system is in a dual-working fluid power generation mode according to an exemplary embodiment.

[0041] Reference numerals:

[0042] 100, integrated heat exchange device; 110, high-pressure evaporator; 1110, first pipeline; 1120, first space; 1130, waste heat inlet; 120, low-pressure evaporator; 1210, second pipeline; 1220, second space; 1230, waste heat outlet; 130, regenerator; 1310, third pipeline; 1320, third space;

[0043] 200, gas-liquid separation device; 210, feed inlet; 220, liquid outlet; 230, gas outlet;

[0044] 310, high-pressure magnetic levitation expander; 320, first pump body; 330, low-pressure magnetic levitation expander; 340, second pump body; 350, third pump body; 360, ninth valve;

[0045] 410, condensing device; 4110, high-pressure condenser; 4120, low-pressure condenser; 420, cooling water generating device;

[0046] 510, fourth pipeline; 520, fifth pipeline; 530, sixth pipeline; 540, seventh pipeline; 550, eighth pipeline; 560, condensation pipeline; 570, ninth pipeline; 580, tenth pipeline;

[0047] 610, first throttle valve; 620, second valve; 630, third valve; 640, fourth valve; 650, fifth valve; 660, sixth valve; 670, second throttle valve; 680, seventh valve; 690, eighth valve. DETAILED DESCRIPTION

[0048] Exemplary embodiments are described in detail herein, with examples illustrated in the accompanying drawings. When the following description refers to the drawings, identical numerals in different figures represent identical or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments are not intended to represent all embodiments consistent with the present invention.

[0049] Recycling waste heat generated during industrial production to generate electricity can effectively alleviate energy shortages and avoid energy waste. This is particularly true for low-grade waste heat, such as liquid waste heat below 100°C, flue gas waste heat at 200°C, or solid sensible heat at 400°C. Due to their low energy density and high recovery costs, the utilization rate of these types of energy in the industrial sector is less than 50%. When the same production line can generate different types of heat sources, or when the same waste heat power generation system is used for different production lines, the heat source parameters such as temperature and flow rate will vary greatly. If the same power generation method is used for all production lines, the heat of the waste heat resources cannot be fully utilized.

[0050] In order to solve the above technical problems, the present invention provides a waste heat power generation system, which reduces the space occupied by the waste heat power generation system by arranging an integrated heat exchange device; by arranging a detection device at the waste heat inlet of the high-pressure evaporator, when the temperature and flow of the heat source detected by the temperature sensor and the flow sensor are in a high and stable state, the waste heat power generation system switches to a single working fluid power generation mode, which can ensure higher power generation efficiency and energy utilization efficiency; otherwise, the waste heat power generation system switches to a dual working fluid power generation mode, which can ensure higher net output power, utilize the heat of waste heat resources in a step-by-step manner, and improve the utilization rate of the heat source, thereby ensuring maximum power generation efficiency.

[0051] A waste heat power generation system according to the present invention will be described in detail below with reference to the accompanying drawings.

[0052] It should be noted that Figure 1 This is the overall structural diagram of the waste heat power generation system in the present invention. Figure 3 as well as Figure 4 The arrows in the figure respectively indicate the flow path and flow direction of the working fluid in the single working fluid power generation mode and the dual working fluid power generation mode, wherein the pipe without an arrow indicates that the working fluid does not pass through the pipe in this mode; in addition, the flow of the working fluid, cooling water or waste heat resources in the waste heat power generation system of the present invention is realized under the action of the pump body, and the entire pump body is not shown in the figure.

[0053] The embodiment of the present invention provides a waste heat power generation system, such as Figure 1As shown, the waste heat power generation system includes an integrated heat exchange device 100, a power generation system and a detection device, wherein the integrated heat exchange device 100 includes a high-pressure evaporator 110, a low-pressure evaporator 120 and a regenerator 130. The high-pressure evaporator 110 is provided with a waste heat inlet 1130, and waste heat resources enter the high-pressure evaporator 110 from the waste heat inlet 1130. The waste heat resources can be gas or liquid. Under the action of the waste heat resources, the high-pressure evaporator 110 and the low-pressure evaporator 120 vaporize at least one liquid working medium, such as butane, pentane, R134a and R245fa, with a boiling point below 50°C, so as to be converted into gas for the power generation system to generate electricity; the power generation system is connected to the integrated heat exchange device 100 and can use the gaseous working medium to generate electricity.

[0054] The detection device is arranged on the waste heat inlet 1130 opened on the high-pressure evaporator 110. The detection device is electrically connected to the controller. The detection device includes a temperature sensor and a flow sensor. When the temperature detected by the temperature sensor is higher than the first set threshold within a set time period, and the flow detected by the flow sensor is higher than the second set threshold within a set time period, it indicates that the waste heat resource is relatively stable. The controller controls the integrated heat exchange device 100 and the power generation system to switch to the single-fluid power generation mode. The set time period, the first set threshold and the second set threshold can be set by those skilled in the art according to actual conditions. For example: if the waste heat resource temperature detected by the temperature sensor is greater than 70°C within 10 minutes, and the waste heat resource flow detected by the flow sensor is greater than 1 cubic meter / second within 10 minutes, it switches to the single-fluid power generation mode; otherwise, it indicates that the waste heat resource is unstable, and the controller controls the switch to the dual-fluid power generation mode. Situations indicating that waste heat resources are unstable include, for example, the temperature of the waste heat resources varying widely within a set time period, sometimes being higher than a first set threshold and sometimes being lower than the first set threshold. Another example is the temperature of the waste heat resources being higher than the first set threshold within a set time period, but the flow rate being always lower than a second set threshold. Alternatively, the temperature of the waste heat resources being lower than the first set threshold and the flow rate being lower than the second set threshold, etc., which are not limited here.

[0055] Experiments have shown that when the heat source temperature is 120°C, the power generation efficiency of the waste heat power generation system in the single-working fluid power generation mode is more than 20% higher than that in the dual-working fluid power generation mode. The dual-working fluid power generation mode exhibits a higher net output power, that is, a higher utilization rate of waste heat resources. In this embodiment, by providing an integrated heat exchange device 100, the space occupied by the waste heat power generation system is reduced; by providing a detection device on the waste heat inlet 1130 of the high-pressure evaporator 110, when the temperature and flow of the heat source detected by the temperature sensor and the flow sensor are at a high and stable state, the waste heat power generation system switches to the single-working fluid power generation mode, which can ensure higher power generation efficiency and energy efficiency; otherwise, the waste heat power generation system switches to the dual-working fluid power generation mode, ensuring higher net output power, step-by-step utilization of the heat of the waste heat resource, and improving the utilization rate of the heat source; the power generation mode is adjusted in time according to the changes in the temperature and flow of the waste heat resource to ensure maximum power generation efficiency.

[0056] In one embodiment, if Figure 1 and Figure 2 As shown, in the high-pressure evaporator 110, the low-pressure evaporator 120, and the regenerator 130, each device includes a pipe and a space that are not connected to each other. The communication between the two devices includes pipe-to-pipe communication, space-to-space communication, or pipe-to-space communication. A first pipe 1110 and a first space 1120 are provided within the high-pressure evaporator 110. The first pipe 1110 contains a first working fluid. The first space 1120 is not connected to the first pipe 1110. A waste heat inlet 1130 is connected to the first space 1120. Waste heat resources enter the first space 1120 through the waste heat inlet 1130, exchange heat with the first working fluid in the first pipe 1110, and the first working fluid is vaporized into a gaseous state.

[0057] The low-pressure evaporator 120 is provided with a second pipe 1210 and a second space 1220. In the single-working fluid power generation mode, the second pipe 1210 includes the first working fluid. In the dual-working fluid power generation mode, the second pipe 1210 includes the second working fluid. The second space 1220 is not connected to the second pipe 1210; the second pipe 1210 is connected to the ninth pipe 570, and the ninth pipe 570 is provided with a seventh valve 680; the first space 1120 is connected to the second space 1220, and the waste heat resource is completed in the first space 1120. After the amount exchange, it enters the second space 1220 of the low-pressure evaporator 120 for reuse; the boiling point of the first working fluid is higher than the boiling point of the second working fluid, and the waste heat resource first completes heat exchange with the first working fluid with a higher boiling point, and the remaining heat is then exchanged with the second working fluid with a lower boiling point, ensuring the step-by-step utilization of heat in the dual-working fluid power generation mode. In addition, the boiling point of the first working fluid must be lower than the temperature that the waste heat resource in the second space 1220 can provide, ensuring that the first working fluid can be vaporized in the second pipeline 1210 in the single-working fluid power generation mode.

[0058] The regenerator 130 includes a third pipe 1310 and a third space 1320. The third pipe 1310 and the third space 1320 are not connected. The third pipe 1310 is connected to the second pipe 1210. A first valve is provided between the third pipe 1310 and the second pipe 1210. The third pipe 1310 is connected to the power generation system through the tenth pipe 580. The tenth pipe 580 is provided with an eighth valve 690.

[0059] The power generation system includes a gas-liquid separation device 200, which is, for example, a gravity sedimentation type gas-liquid separation device, a baffle separation type gas-liquid separation device, a centrifugal separation type gas-liquid separation device, etc. The gas-liquid separation device 200 includes a liquid outlet 220, a feed port 210 and a gas outlet 230, wherein the feed port 210 is arranged in the middle section of the gas-liquid separation device 200, the feed port 210 is connected to the first pipeline 1110, and the first working medium in a gas-liquid mixed state enters the gas-liquid separation device 200 from the feed port 210 for separation; the liquid outlet 220 is arranged at the bottom of the gas-liquid separation device 200, and the gas outlet 230 is arranged at the top of the gas-liquid separation device 200, the liquid outlet 220 is connected to the second pipeline 1210 through the fourth pipeline 510, and the fourth pipeline 510 is provided with a first throttle valve 610, and the liquid outlet 220 is also connected to the third space 1320 through the fifth pipeline 520, and the fifth pipeline 520 is provided with a second valve 620.

[0060] The specific mode switching process is as follows: In the single working fluid power generation mode, refer to Figure 1 and Figure 3The controller controls the first throttle valve 610 to open, the first valve to close, the second valve 620 to close, the seventh valve 680 to open, and the eighth valve 690 to close. The gas-liquid mixed first working medium in the high-pressure evaporator 110 enters the gas-liquid separation device 200 through the feed inlet 210. The separated gaseous first working medium enters the power generation system from the gas outlet 230 to generate electricity. At the same time, because the first throttle valve 610 is open and the second valve 620 is closed, the separated liquid first working medium enters the fourth pipeline 510 from the liquid outlet 220. After throttling and cooling by the first throttle valve 610, it enters the second pipeline 1210 of the low-pressure evaporator 120, exchanges heat with the waste heat resource again, and becomes gaseous. It then enters the power generation system through the ninth pipeline 570 to generate electricity.

[0061] In the dual-medium power generation mode, refer to Figure 1 and Figure 4 The controller controls the first valve to open, the second valve 620 to open, the first throttle valve 610 to close, the seventh valve 680 to close, and the eighth valve 690 to open. The gas-liquid mixture of the first working medium in the high-pressure evaporator 110 enters the gas-liquid separation device 200 through the feed port 210. The separated gaseous first working medium enters the power generation system from the gas outlet 230 to generate electricity. At the same time, the first valve opens, and the second working medium in the second pipe 1210 of the low-pressure evaporator 120 enters the third pipe 1310 of the regenerator 130. Since the first throttle valve 610 is closed and the second valve 620 is opened, the separated liquid first working medium enters the third space 1320 of the regenerator 130 through the fifth pipe 520, heating the second working medium in the third pipe 1310. The gaseous second working medium enters the power generation system through the tenth pipe 580 to generate electricity.

[0062] In this embodiment, switching between two power generation modes is achieved by opening and closing the valve and different connections between the pipeline and the space, and the control method is simple; the liquid first working fluid separated in the gas-liquid separation device 200 is reused in different ways, thereby improving the energy utilization efficiency; by setting the first throttle valve 610, the liquid first working fluid undergoes adiabatic expansion when passing through the first throttle valve 610, resulting in a decrease in molecular kinetic energy and conversion into potential energy, thereby lowering the temperature. When the cooled first working fluid enters the second pipeline 1210 and exchanges heat with the waste heat resource, the degree of gasification can be improved, thereby improving the power generation efficiency.

[0063] In one embodiment, continue to refer to Figure 1The second pipeline 1210 is connected to the working fluid storage device (not shown in the figure) through a supplementary pipeline (not shown in the figure). A supplementary valve (not shown in the figure) and a pump body are provided on the supplementary pipeline. When the single working fluid power generation mode is switched to the dual working fluid power generation mode, the first working fluid in the second pipeline 1210 is emptied, and the supplementary valve is opened. The second working fluid enters the second pipeline 1210 from the working fluid storage device under the action of the pump body; when the dual working fluid power generation mode is switched to the single working fluid power generation mode, the supplementary valve is opened, and the second working fluid is discharged from the second pipeline 1210 to the working fluid storage device. After emptying, the system is started to generate electricity, and the first working fluid enters the second pipeline 1210.

[0064] Such a design provides conditions for switching between a single working fluid and a dual working fluid, and also avoids the first working fluid and the second working fluid from mixing in the second pipe 1210, thereby affecting the power generation effect.

[0065] In one embodiment, reference Figure 1 The power generation system includes a first circuit and a second circuit, wherein the first circuit includes a high-pressure magnetic levitation expander 310, a condensing device 410 and a first pump body 320 connected in sequence, the high-pressure magnetic levitation expander 310 is connected to the gas outlet 230 of the gas-liquid separation device 200, and the first pump body 320 is connected to the first pipeline 1110; the second circuit includes a low-pressure magnetic levitation expander 330, a condensing device 410 and a second pump body 340 connected in sequence, the low-pressure magnetic levitation expander 330 is connected to the second pipeline 1210, and the second pump body 340 is connected to the second pipeline 1210. A third pump body 350 and a ninth valve 360 ​​are also provided on the second circuit. The third pump body 350 and the second pump body 340 work together to ensure the delivery power of the working medium.

[0066] The working process of the magnetic levitation expander includes: high-temperature and high-pressure working fluid enters the expander, expands (pressure decreases) in the expander, drives the rotor (such as turbine blades or screw rotors) to rotate, and converts thermal energy into mechanical energy. The rotor of the expander is connected to the generator through a coupling, driving the rotor of the generator to rotate and cut the magnetic lines of force. The generator is a magnetic levitation generator, and the rotor is suspended under the action of magnetic bearings, which can reduce friction loss and improve power generation efficiency.

[0067] By setting up the first circuit and the second circuit, which are connected to the high-pressure evaporator 110 and the low-pressure evaporator 120 respectively, the high-pressure power generation cycle and the low-pressure power generation cycle are completed, the recycling of the first working fluid and the second working fluid is realized, and the raw material cost is saved.

[0068] In one embodiment, if Figure 1As shown, the condensing device 410 includes a high-pressure condenser 4110 and a low-pressure condenser 4120. A first working fluid pipeline and a second working fluid pipeline are provided in the high-pressure condenser 4110. The first working fluid pipeline and the second working fluid pipeline are not connected to each other. The first working fluid pipeline is connected to the high-pressure magnetic levitation expander 310 and the first pump body 320, and is used to accommodate the first working fluid delivered by the high-pressure magnetic levitation expander 310; the low-pressure magnetic levitation expander 330 and the second working fluid pipeline are connected via a sixth pipeline 530, on which a third valve 630 is provided. The second working fluid pipeline is also connected to the second pump body 340, and is used to accommodate the first working fluid delivered by the low-pressure magnetic levitation expander 330; the low-pressure magnetic levitation expander 330 and the third working fluid pipeline of the low-pressure condenser 4120 are connected via a seventh pipeline 540, on which a fourth valve 640 is provided. The third working fluid pipeline is connected to the second pump body 340, and is used to accommodate the second working fluid.

[0069] It is understandable that the high-pressure condenser 4110 does not mean that its voltage is higher than the voltage of the low-pressure condenser 4120, but is only used to distinguish the devices on the two lines.

[0070] By configuring the condensing device 410 to include a high-pressure condenser 4110 and a low-pressure condenser 4120 and connecting them through different pipelines, a good condensing effect is ensured in different power generation modes.

[0071] In one embodiment, if Figure 1 As shown, the waste heat power generation system also includes a cooling system, which includes a cooling water generating device 420. The cooling water generating device 420 is connected in series with the first cooling water pipe of the high-pressure condenser 4110 and the second cooling water pipe of the low-pressure condenser 4120. The series connection means that when the fifth valve 650 is open, the cooling water generated by the cooling water generating device 420 will first pass through the first cooling water pipe of the high-pressure condenser 4110, then pass through the second cooling water pipe of the low-pressure condenser 4120, and finally return to the cooling water generating device 420. The first cooling water pipe and the second cooling water pipe are both used to hold cooling water for heat exchange with the first working fluid pipe, the second working fluid pipe, and the third working fluid pipe in the high-pressure condenser 4110 or the low-pressure condenser 4120 to achieve condensation of the first working fluid and the second working fluid. A fifth valve 650 is provided between the first cooling water pipe and the second cooling water pipe. The first cooling water pipe and the cooling water generating device 420 are connected via an eighth pipe 550, and the eighth pipe 550 is provided with a sixth valve 660.

[0072] Since the boiling point of the first working fluid is higher than that of the second working fluid, that is, the temperature of the gaseous first working fluid is higher than the temperature of the gaseous second working fluid, the cooling water is utilized in stages by connecting the first cooling water pipe of the high-pressure condenser 4110 and the second cooling water pipe of the low-pressure condenser 4120 in series. The cooling water first condenses the first working fluid with a higher temperature in the first cooling water pipe, exchanges heat with the first working fluid, and the temperature rises. Then, the cooling water condenses the second working fluid with a lower temperature in the second cooling water pipe, exchanges heat with the second working fluid. This reduces the use of cooling water without affecting the condensation effect, and ensures the condensation effect even when the supply of cooling water is insufficient.

[0073] In one embodiment, if Figure 1 and Figure 3 As shown, the third valve 630, the fourth valve 640, the fifth valve 650 and the sixth valve 660 are all electrically connected to the controller. When the waste heat power generation system is in the single working fluid power generation mode, the controller controls the third valve 630 to open, the fourth valve 640 to close, the fifth valve 650 to close, and the sixth valve 660 to open; the gaseous first working fluid in the high-pressure magnetic levitation expander 310 is condensed into liquid in the first working fluid pipeline of the high-pressure condenser 4110 and is transported to the first pipeline 1110 of the high-pressure evaporator 110 by the first pump body 320; due to the third valve 630 The fourth valve 640 is opened and closed, and the gaseous first working fluid in the low-pressure magnetic levitation expander 330 enters the second working fluid pipeline of the high-pressure condenser 4110 through the sixth pipeline 530, is condensed into liquid, and is transported to the second pipeline 1210 by the second pump body 340; since the fifth valve 650 is closed and the sixth valve 660 is opened, the cooling water generated by the cooling water generating device 420 passes through the first cooling water pipeline and the eighth pipeline 550 in turn and then flows back to the cooling water generating device 420, that is, the condensation of the first working fluid in the two circuits is completed through the high-pressure condenser 4110.

[0074] In another embodiment, Figure 1 and Figure 4As shown, when the waste heat power generation system is in the dual-working medium power generation mode, the controller controls the third valve 630 to be closed, the fourth valve 640 to be opened, the fifth valve 650 to be opened, and the sixth valve 660 to be closed; the gaseous first working medium in the high-pressure magnetic levitation expander 310 is condensed into liquid in the first working medium pipeline of the high-pressure condenser 4110, and is transported by the first pump body 320 to the first pipeline 1110 of the high-pressure evaporator 110; since the third valve 630 is closed and the fourth valve 640 is opened, the gaseous second working medium in the low-pressure magnetic levitation expander 330 passes through the seventh pipeline The cooling water flows through the channel 540 into the third working fluid pipeline, is condensed into liquid in the low-pressure condenser 4120, and is transported by the second pump body 340 to the second pipeline 1210 of the low-pressure evaporator 120; since the fifth valve 650 is opened and the sixth valve 660 is closed, the cooling water generated by the cooling water generating device 420 passes through the first cooling water pipeline and the second cooling water pipeline in sequence and then flows back to the cooling water generating device 420, thereby realizing the cooling water circulation; that is, the condensation of the first working fluid is completed by the high-pressure condenser 4110, and the condensation of the second working fluid is completed by the low-pressure condenser 4120.

[0075] With such a design, in the single-working-fluid power generation mode, since only the first working fluid participates in the circulation of the waste heat power generation system, the first working fluid in the two circuits is condensed only through the high-pressure condenser 4110; while in the dual-working-fluid power generation mode, the high-pressure condenser 4110 and the low-pressure condenser 4120 are used to condense the first working fluid with a higher temperature and the second working fluid with a lower temperature, respectively, thereby ensuring the condensation effect, reducing the amount of cooling water used, and thereby reducing the energy consumption of the cooling water generating device 420 and saving energy.

[0076] In one embodiment, if Figures 1 to 4 As shown, the third space 1320 of the regenerator 130 is connected to the first working fluid pipeline through the condensation pipe 560, and a second throttle valve 670 is provided on the condensation pipe 560, and the second throttle valve 670 is electrically connected to the controller; when in the single working fluid power generation mode, the controller controls the second throttle valve 670 to close; when in the dual working fluid power generation mode, the controller controls the second throttle valve 670 to open, and the first working fluid in the third space 1320 flows through the condensation pipe 560 to the high-pressure condenser 4110 for condensation, and returns to the first pipeline 1110 under the action of the first pump body 320.

[0077] In this embodiment, by setting up a condensing pipe 560 and a second throttle valve 670, when switching to the dual-fluid power generation mode, the first working fluid in the third space 1320 used to heat the second working fluid in the third pipe 1310 flows through the condensing pipe 560 to the high-pressure condenser 4110 for condensation after the cooling effect of the second throttle valve 670, thereby avoiding the waste of the first working fluid and saving energy.

[0078] In one embodiment, if Figure 1 and Figure 2 As shown, the low-pressure evaporator 120 is further provided with a waste heat outlet 1230 , which is in communication with the second space 1220 . Thus, the waste heat resources that complete heat exchange in the second space 1220 are discharged from the waste heat outlet 1230 .

[0079] In one embodiment, if Figure 1 and Figure 2 As shown, a waste heat detection device is provided on the waste heat outlet 1230, which can detect the temperature and flow of the used waste heat resources again and compare them with the data detected at the waste heat inlet 1130, so as to determine the utilization efficiency of the heat of the waste heat resources, so that technical personnel can adjust the working fluid, setting parameters, etc. of the waste heat power generation system according to the data.

[0080] The overall power generation process of a waste heat power generation system in the above embodiment is as follows:

[0081] When the temperature detected by the temperature sensor is higher than a first threshold value within a set time period, and the flow rate detected by the flow sensor is higher than a second threshold value within a set time period, indicating that the waste heat resource is relatively stable, the controller controls the integrated heat exchange device 100 and the power generation system to switch to a single working fluid power generation mode. Specifically, the controller controls the first throttle valve 610 to open, the first valve to close, the second valve 620 to close, the seventh valve 680 to open, and the eighth valve 690 to close. The gas-liquid mixed first working medium in the high-pressure evaporator 110 enters the gas-liquid separation device 200 through the feed port 210, and the separated gaseous first working medium enters the high-pressure magnetic levitation expander 310 from the gas outlet 230 to generate electricity; at the same time, since the first throttle valve 610 is opened and the second valve 620 is closed, the separated liquid first working medium enters the fourth pipeline 510 from the liquid outlet 220, and after the throttling and cooling effect of the throttle valve, enters the second pipeline 1210 of the low-pressure evaporator 120, exchanges heat with the waste heat resource again to become gaseous, and enters the low-pressure magnetic levitation expander 330 through the ninth pipeline 570 to generate electricity; in addition, the controller controls the third valve 630 to open, the fourth valve 640 to close, and the fifth valve 650 to close. , the sixth valve 660 is opened; the gaseous first working medium in the high-pressure magnetic levitation expander 310 is condensed into liquid in the first working medium pipeline of the high-pressure condenser 4110, and is transported to the first pipeline 1110 of the high-pressure evaporator 110 by the first pump body 320; since the third valve 630 is opened and the fourth valve 640 is closed, the gaseous first working medium in the low-pressure magnetic levitation expander 330 enters the second working medium pipeline of the high-pressure condenser 4110 through the sixth pipeline 530, is condensed into liquid, and is transported to the second pipeline 1210 by the second pump body 340; since the fifth valve 650 is closed and the sixth valve 660 is opened, the cooling water generated by the cooling water generating device 420 passes through the first cooling water pipeline and the eighth pipeline 550 in sequence and then flows back to the cooling water generating device 420.

[0082] When the parameters detected by the temperature sensor and the flow sensor are not as described above, it indicates that the waste heat resource is unstable. After the first working fluid in the second pipeline 1210 is emptied, the replenishing valve is opened, and the second working fluid enters the second pipeline 1210 from the working fluid storage device under the action of the pump body, switching to the dual-working fluid power generation mode. The controller controls the first valve to open, the second valve 620 to open, the first throttle valve 610 to close, the seventh valve 680 to close, and the eighth valve 690 to open. The gas-liquid mixed first working medium in the high-pressure evaporator 110 enters the gas-liquid separation device 200 through the feed port 210, and the separated gaseous first working medium enters the high-pressure magnetic levitation expander 310 from the gas outlet 230 to generate electricity; at the same time, the first valve is opened, and the second working medium in the second pipe 1210 of the low-pressure evaporator 120 enters the third pipe 1310 of the regenerator 130. Since the first throttle valve 610 is closed and the second valve 620 is opened, the separated liquid first working medium enters the third space 1320 of the regenerator 130 through the fifth pipe 520, heating the second working medium in the third pipe 1310, and the gaseous second working medium enters the low-pressure magnetic levitation expander 330 through the tenth pipe 580 to generate electricity; in addition, the controller controls the third valve 630 to close, the fourth valve 640 to open, and the fifth valve 650 to open. Valve 650 is opened and the sixth valve 660 is closed; the gaseous first working fluid in the high-pressure magnetic levitation expander 310 is condensed into liquid in the first working fluid pipeline of the high-pressure condenser 4110, and is transported to the first pipeline 1110 of the high-pressure evaporator 110 by the first pump body 320; since the third valve 630 is closed and the fourth valve 640 is opened, the gaseous second working fluid in the low-pressure magnetic levitation expander 330 enters the third working fluid pipeline through the seventh pipeline 540, is condensed into liquid in the low-pressure condenser 4120, and is transported to the second pipeline 1210 of the low-pressure evaporator 120 by the second pump body 340; since the fifth valve 650 is opened and the sixth valve 660 is closed, the cooling water generated by the cooling water generating device 420 passes through the first cooling water pipeline and the second cooling water pipeline in sequence and then flows back to the cooling water generating device 420, realizing cooling water circulation.

[0083] When switching from the dual-working fluid power generation mode to the single-working fluid power generation mode again, the replenishing valve is opened, and the second working fluid is discharged from the second pipeline 1210 to the working fluid storage device. After being emptied, the system is started to generate electricity, and the first working fluid enters the second pipeline 1210 to perform a power generation cycle.

[0084] In the present invention, by arranging switching of the circuits inside the integrated heat exchange device 100, between the integrated heat exchange device 100 and the gas-liquid separation device 200, and the condensing device 410, energy consumption is reduced from multiple angles and energy utilization efficiency is improved.

[0085] It should be noted that the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of technical features indicated. Therefore, features defined as "first" or "second" may explicitly or implicitly include at least one of such features.

[0086] In the present invention, unless otherwise specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection; direct connection, or indirect connection through an intermediate medium; internal communication between two components, or interaction between two components, unless otherwise specified. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0087] In the description of this specification, the reference terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and features of different embodiments or examples without contradiction.

[0088] Other embodiments of the present invention will readily occur to those skilled in the art after considering the specification and practicing the invention disclosed herein. The present invention is intended to cover any variations, uses, or adaptations of the present invention that follow the general principles of the invention and include common knowledge or customary techniques in the art not disclosed herein.

Claims

1. A waste heat power generation system, characterized in that: The waste heat power generation system includes: An integrated heat exchange device (100) comprises a high-pressure evaporator (110), a low-pressure evaporator (120), and a regenerator (130); a waste heat inlet (1130) is provided on the high-pressure evaporator (110); and the integrated heat exchange device (100) is capable of gasifying at least one liquid working medium under the action of waste heat resources; A power generation system connected to the integrated heat exchange device (100), the power generation system being used to generate electricity using the gaseous working medium; A detection device is provided on the waste heat inlet (1130), the detection device is electrically connected to a controller, the controller is used to receive the detection result sent by the detection device, and the detection device includes a temperature sensor and a flow sensor; When the temperature detected by the temperature sensor is higher than a first set threshold value within a set time period, and the flow rate detected by the flow sensor is higher than a second set threshold value within the set time period, the controller controls the integrated heat exchange device (100) and the power generation system to switch to a single-working-fluid power generation mode; otherwise, the controller controls the integrated heat exchange device (100) and the power generation system to switch to a dual-working-fluid power generation mode; A first pipe (1110) and a first space (1120) are provided in the high-pressure evaporator (110); the first pipe (1110) contains a first working medium; the first space (1120) is not connected to the first pipe (1110); and the waste heat inlet (1130) is connected to the first space (1120); A second pipe (1210) and a second space (1220) are provided in the low-pressure evaporator (120); in the single-working-fluid power generation mode, the second pipe (1210) contains the first working fluid; in the dual-working-fluid power generation mode, the second pipe (1210) contains the second working fluid; the second space (1220) is not connected to the second pipe (1210); the first space (1120) is connected to the second space (1220); the first space (1120) and the second space (1220) are used to accommodate waste heat resources; the boiling point of the first working fluid is higher than the boiling point of the second working fluid; The regenerator (130) comprises a third pipe (1310) and a third space (1320); the third pipe (1310) and the third space (1320) are not connected; the third pipe (1310) is connected to the second pipe (1210); and a first valve is provided between the third pipe (1310) and the second pipe (1210); The power generation system comprises a gas-liquid separation device (200), a feed port (210) of the gas-liquid separation device (200) being in communication with the first pipeline (1110), a liquid outlet (220) of the gas-liquid separation device (200) being in communication with the second pipeline (1210) via a fourth pipeline (510), a first throttle valve (610) being provided on the fourth pipeline (510), and the liquid outlet (220) being in communication with the third space (1320) via a fifth pipeline (520), a second valve (620) being provided on the fifth pipeline (520); In the single-working-fluid power generation mode, the controller controls the first throttle valve (610) to open, the first valve to close, and the second valve (620) to close; in the dual-working-fluid power generation mode, the controller controls the first valve to open, the second valve (620) to open, and the first throttle valve (610) to close.

2. The waste heat power generation system according to claim 1, characterized in that: The second pipeline (1210) is connected to the working medium storage device via a supplementary pipeline, and a supplementary valve is provided on the supplementary pipeline; When the single working fluid power generation mode is switched to the dual working fluid power generation mode, the supplementary valve is opened, and the second working fluid enters the second pipeline (1210) from the working fluid storage device; when the dual working fluid power generation mode is switched to the single working fluid power generation mode, the supplementary valve is opened, and the second working fluid is discharged from the second pipeline (1210) to the working fluid storage device.

3. The waste heat power generation system according to claim 1, characterized in that: The power generation system includes a first circuit and a second circuit, wherein: The first circuit comprises a high-pressure magnetic levitation expander (310), a condensing device (410), and a first pump body (320) connected in sequence, the high-pressure magnetic levitation expander (310) being in communication with the gas outlet (230) of the gas-liquid separation device (200), and the first pump body (320) being connected to the first pipeline (1110); The second circuit comprises a low-pressure magnetic levitation expander (330), the condensing device (410), and a second pump body (340) connected in sequence; the low-pressure magnetic levitation expander (330) is in communication with the second pipeline (1210); and the second pump body (340) is connected to the second pipeline (1210).

4. The waste heat power generation system according to claim 3, characterized in that: The condensing device (410) comprises a high-pressure condenser (4110) and a low-pressure condenser (4120), wherein a first working fluid pipeline and a second working fluid pipeline are provided in the high-pressure condenser (4110). The first working fluid pipeline is in communication with the high-pressure magnetic levitation expander (310); The low-pressure magnetic levitation expander (330) and the second working medium pipeline are connected via a sixth pipeline (530), and a third valve (630) is provided on the sixth pipeline (530); The low-pressure magnetic levitation expander (330) and the third working medium pipeline of the low-pressure condenser (4120) are connected via a seventh pipeline (540), and a fourth valve (640) is provided on the seventh pipeline (540).

5. The waste heat power generation system according to claim 4, characterized in that: The waste heat power generation system further includes a cooling system, the cooling system including a cooling water generating device (420), a fifth valve (650) being provided between the first cooling water pipe of the high-pressure condenser (4110) and the second cooling water pipe of the low-pressure condenser (4120), and when the fifth valve (650) is opened, the cooling water generating device (420) is connected in series with the first cooling water pipe and the second cooling water pipe; The first cooling water pipeline and the cooling water generating device (420) are also connected via an eighth pipeline (550), and a sixth valve (660) is provided on the eighth pipeline (550).

6. The waste heat power generation system according to claim 5, characterized in that: The third valve (630), the fourth valve (640), the fifth valve (650) and the sixth valve (660) are all electrically connected to the controller. When in the single working fluid power generation mode, the controller controls the third valve (630) to open, the fourth valve (640) to close, the fifth valve (650) to close, and the sixth valve (660) to open; The first working fluid in the gaseous state in the high-pressure magnetic levitation expander (310) is condensed into a liquid state in the first working fluid pipeline of the high-pressure condenser (4110), and is transported to the first pipeline (1110) by the first pump body (320); the first working fluid in the gaseous state in the low-pressure magnetic levitation expander (330) is condensed into a liquid state in the second working fluid pipeline of the high-pressure condenser (4110), and is transported to the second pipeline (1210) by the second pump body (340); the cooling water generated by the cooling water generating device (420) passes through the first cooling water pipeline and the eighth pipeline (550) in sequence, and then flows back to the cooling water generating device (420).

7. The waste heat power generation system according to claim 5, characterized in that: When in the dual-medium power generation mode, the controller controls the third valve (630) to be closed, the fourth valve (640) to be opened, the fifth valve (650) to be opened, and the sixth valve (660) to be closed; The first working fluid in the high-pressure magnetic levitation expander (310) in a gaseous state is condensed into a liquid state in the high-pressure condenser (4110) and transported to the first pipeline (1110) by the first pump body (320); the second working fluid in the low-pressure magnetic levitation expander (330) in a gaseous state is condensed into a liquid state in the low-pressure condenser (4120) and transported to the second pipeline (1210) by the second pump body (340); the cooling water generated by the cooling water generating device (420) passes through the first cooling water pipeline and the second cooling water pipeline in sequence and then flows back to the cooling water generating device (420).

8. The waste heat power generation system according to claim 4, characterized in that: The third space (1320) of the regenerator (130) is in communication with the first working medium pipeline via a condensation pipeline (560); a second throttle valve (670) is provided on the condensation pipeline (560); and the second throttle valve (670) is electrically connected to the controller; When in the single working fluid power generation mode, the controller controls the second throttle valve (670) to close; when in the dual working fluid power generation mode, the controller controls the second throttle valve (670) to open, and the first working fluid in the third space (1320) flows to the high-pressure condenser (4110) for condensation.

9. The waste heat power generation system according to any one of claims 1 to 8, characterized in that: The low-pressure evaporator (120) is also provided with a waste heat outlet (1230), and the waste heat outlet (1230) is in communication with the second space (1220).

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