A CO2 thermosensitive crystallization photothermal regeneration power generation system and method

Abstract

The present invention discloses a CO2 thermosensitive crystallization photothermal regeneration power generation system and method, which belongs to the field of photothermal power generation, including: utilizing the crystallization property of guanidine salt and carbonate after combination, so that photothermal drive CO2 desorption in carbonate-based guanidine salt solid crystals and cyclic absorption and regeneration in an alkaline absorbent, thereby forming a proton concentration difference potential at the anode and cathode of the system and discharging it to the outside, thereby realizing the conversion of photothermal energy into electrical energy. The present invention can also be adapted to heat sources of different grades to achieve efficient power generation. In addition, the system can also be applied to CO2 of different concentrations to achieve the integration of CO2 capture and thermal power generation.

Description

Technical Field

[0001] The present invention relates to the field of photothermal power generation, and more specifically, to a power generation system and method for photothermal regeneration of CO2 thermosensitive crystals. Background Art

[0002] Solar energy represents a vast, yet largely untapped, renewable energy source. In terms of available quantity, it is the most promising source of renewable energy. The average solar radiation received by Earth is approximately 162,000 TW, which is four orders of magnitude greater than the current global energy demand. Yet, only a small fraction of this energy is used to generate electricity. There are many different ways to convert solar energy into electricity. Currently, the two most common methods are photovoltaic (PV) and photothermal (CPT). PV uses the photovoltaic effect of semiconductor materials to convert solar radiation directly into electrical energy. Photothermal power generation, on the other hand, involves first collecting solar radiation with a solar collector and converting it into heat, which is then used directly to generate electricity.

[0003] There are two main types of solar thermal power generation technologies at present. One is the conversion of light energy into heat energy into mechanical energy into electrical energy (concentrated solar power generation technology, CSP) based on the principle of thermal power generation, and the other is solar semiconductor temperature difference power generation based on the solid Seebeck effect.

[0004] Concentrated solar power (CSP) technology is currently the most promising form of commercialization. Based on the concentration method, CSP can be further divided into two major systems: electric focusing and line focusing. Point-focusing systems primarily include tower and dish CSP, while line focusing systems primarily include trough and linear Fresnel CSP. Meanwhile, many new CSP-like systems are being developed. These systems also achieve CSP power generation through the conversion of light, heat, mechanical energy, and electricity, but with greater diversity in the light-to-heat and heat-to-mechanical energy conversion methods. Representative systems include: solar chimneys, which use air heated under a glass or other transparent material canopy to drive a turbine generator; solar ponds, which use solar energy to rapidly raise the temperature of a saltwater pool bottom, driving a low-boiling-point working fluid to generate electricity; and solar thermoacoustic systems, which use the thermoacoustic effect to cause gas (helium) to vibrate under a temperature gradient, driving a linear alternating current generator.

[0005] Heat generated by solar radiation can also be coupled to a thermoelectric generator (TEG) to generate electricity. TEGs primarily rely on the Seebeck effect in solid materials to convert thermal energy into electricity. In solar thermal power generation systems, devices that replace traditional mechanical heat engines with TEGs are called solar thermal generators (STEGs). A solar thermal generator (STEG) is a system designed to convert solar energy into electricity through a thermoelectric generator (TEG). From an energy perspective, in a STEG, solar energy is first converted into heat and then directly into electricity. The simplest STEG requires only three components: a solar collector, a thermoelectric generator (TEG), and a heat sink. A STEG is formed by placing a TEG between a solar absorber and a heat sink. The solar absorber absorbs solar radiation, causing its temperature to rise, which is then connected to one side of the TEG, while the heat sink remains at a constant temperature. This creates a temperature gradient in the TEG, which in turn generates a voltage gradient due to the Seebeck effect. If the TEG is connected to a load, a thermoelectric current is generated, which drives the load, ultimately achieving solar thermal power generation. Current research on STEG systems is still primarily focused on:

[0006] 1. Increase the temperature difference between the hot and cold ends T h -T c (Improved solar collectors and radiators);

[0007] 2. Improve the average thermoelectric quality factor (ZT) of thermoelectric materials (improve thermoelectric generators). However, due to the low energy density of solar radiation, which leads to a small temperature difference between the two ends of the TEG system, the low Seebeck coefficient of the TEG system itself, and the difficulty in regulating the coupling between thermal conductivity and electrical conductivity, the application of STEG systems is still not ideal.

[0008] Thermoelectrochemical cycle batteries based on entropy change of liquid-based systems are expected to show great advantages in the field of solar thermal power generation. Summary of the Invention

[0009] The present invention aims to overcome the shortcomings of existing technologies by providing a CO2 thermosensitive crystallization photothermal regeneration power generation system and method. This system achieves the conversion of photothermal energy into electrical energy and can be adapted to various heat sources to achieve efficient power generation. Furthermore, the system can be applied to CO2 at varying concentrations, achieving integrated CO2 capture and thermal power generation.

[0010] The object of the present invention is achieved through the following solutions:

[0011] A CO2 thermosensitive crystallization photothermal regeneration power generation system comprises: a load, a battery system, a CO2 desorption tank, a CO2 buffer tank and a CO2 absorption tank, wherein the battery system comprises a battery anode gas chamber, a battery anode, a battery anode region, a cation exchange membrane, a battery cathode region, a battery cathode, a battery cathode gas chamber and a battery system; the load is connected to the battery anode and the battery cathode of the battery system, and is used to receive and detect the electric energy output by the battery; the battery anode gas chamber is connected to the flow channel of the battery cathode gas chamber, and is used to realize the hydrogen circulation system of the battery; during the reaction process, a hydrogen evolution reaction occurs on the battery cathode to decompose water to produce H2, and the gas is transported to the anode region through a one-way pipeline, and an electrochemical hydrogen oxidation reaction occurs on the battery anode, and H2 loses electrons to generate H + The battery anode and cathode are separated by a cation exchange membrane. Electrochemical hydrogen oxidation occurs at the battery anode, and H2 loses electrons to generate H + , which reduces the alkalinity of the anode area; under the action of the electric field, the cations in the anode area of ​​the battery reach the cathode area of ​​the battery through the cation exchange membrane to ensure charge balance; the anode liquid after the reaction is CO3 2- / HCO3 - It enters the CO2 absorption tank to absorb the CO2 desorbed by photothermal desorption and converts it into HCO3 - Realize recycling and regeneration of HCO3 - The solution circulates to the cathode area as cathode reaction raw material. The reaction equation is as follows:

[0012] Anode reaction: H2→2H + +2e -

[0013] Anode reaction: 2H + +2CO3 2- →2HCO3 -

[0014] CO2 absorption tank reaction: CO3 2- +CO2+H2O→2HCO3 -

[0015] The cathode of the battery is a hydrogen evolution electrode, which undergoes an electrochemical reduction reaction to decompose water to produce H2 and OH - , thereby increasing the alkalinity of the cathode liquid and being used to absorb the circulating CO2 desorbed by photothermal desorption to generate bicarbonate solution. The reaction equation is as follows:

[0016] Cathode reaction: 2H2O+2e - →H2+2OH -

[0017] Cathode zone reaction: 2OH - +2CO2→2HCO3 -

[0018] In the cathode zone, salts recycled from the CO2 photothermal desorption tank are crystallized with the cathode liquid after the reaction, and the salts include guanidine salt G;

[0019] Guanidine salt G from HCO3 - Grab a proton H + and combined with an HCO3 - G-H2CO3 crystals are formed and precipitated, and the alkaline absorbent CO3 is regenerated through this process. 2- The solution is transported to the anode area for recycling, and the remaining guanidine salt after desorption of CO2 is recycled back to the cathode area for use; the guanidine salt G and HCO3 - The crystallization reaction is as follows:

[0020] Guanidine-carbonic acid crystallization reaction: G+2HCO3 - →G-H2CO3↓+CO3 2-

[0021] The G-H2CO3 crystals precipitated from the cathode liquid are transported to the CO2 desorption tank, where they are heated and mixed by photothermal energy to release CO2. The released CO2 is then transported to the CO2 buffer tank for short-term storage. Subsequently, the CO2 is divided into two streams and respectively introduced into the CO2 absorption tank for regeneration of the cathode raw liquid and into the cathode area for acidification of the cathode liquid to reduce the pH value. The reaction formula is as follows:

[0022] CO2 desorption tank reaction: G-H2CO3→G+H2O+CO2↑

[0023] CO2 is desorbed and released under light and heat, and the guanidine salt G is recycled.

[0024] Furthermore, the battery anode includes a platinum electrode and a platinum-plated nickel mesh.

[0025] Furthermore, the CO2 absorption tank also serves as an anode liquid buffer tank.

[0026] Furthermore, the battery cathode includes a platinum electrode and a platinum-plated nickel mesh.

[0027] A CO2 thermosensitive crystallization photothermal regeneration power generation system, in which the carbonate solution in the CO2 thermosensitive crystallization photothermal regeneration power generation system as described in any of the above items is used as a CO2 absorbent to adapt to different types of cations, wherein the carbonate solution can be replaced by any one of KOH, NaOH, ammonia water, monoethanolamine, ethylenediamine, triethanolamine, and piperazine.

[0028] A CO2 thermosensitive crystal photothermal regeneration power generation system, as described in any of the above CO2 thermosensitive crystal photothermal regeneration power generation systems, uses electrode reactions as hydrogen evolution reaction HER and hydrogen oxidation reaction HOR, and the hydrogen evolution reaction HER and hydrogen oxidation reaction HOR can be replaced by oxygen evolution reaction OER and oxygen reduction reaction ORR.

[0029] A CO2 thermosensitive crystal photothermal regeneration power generation system, as described in any of the above CO2 thermosensitive crystal photothermal regeneration power generation systems, the electrode reaction used can be replaced by a proton H + Any electrochemical reaction that transfers.

[0030] A CO2 thermosensitive crystal photothermal regeneration power generation method converts photothermal energy into stable electrical energy output through hydrogen circulation reaction, guanidine salt-CO2 crystal thermosensitive regeneration cycle and fluid pumping cycle, specifically comprising the following sub-steps:

[0031] By utilizing the crystallization properties of guanidine salts combined with carbonates, photothermal-driven CO2 desorption in solid crystals is carried out and cyclically absorbed and regenerated in an alkaline absorbent, thereby forming a proton concentration difference potential at the anode and cathode of the system and discharging it externally, thereby realizing the conversion of photothermal energy into electrical energy.

[0032] Furthermore, the crystallization property of guanidine salt combined with carbonate is utilized to desorb CO2 in the solid crystal driven by light and heat and circulate the absorption and regeneration in the alkaline absorbent, thereby forming a proton concentration difference potential at the anode and cathode of the system and discharging it externally, thereby realizing the conversion of light and heat energy into electrical energy. Specifically, the process includes the following sub-steps:

[0033] First, a CO2 absorbent is added to the anode region to increase the pH value of the solution, and a cathode solute is added to the cathode region and CO2 is introduced to maintain the pH value. The anode and cathode of the system are separated by a cation exchange membrane. At this time, there is a proton concentration difference ΔpH between the anode and cathode of the system, which generates a potential difference. In addition, by circulating hydrogen as a mass-electrode coupling agent to construct a redox couple and a proton carrier, the anode undergoes an H2 oxidation reaction HOR, which loses electrons and releases protons H + , acidifying the solution and neutralizing the alkalinity of the anode area; the cathode undergoes hydrogen evolution reaction (HER) to obtain electrons and extract H from the solution + , alkalize the solution, and the generated H2 is then passed into the anode for recycling. During the discharge process, the cation exchange membrane separates the cathode and anode and allows cations in the anode area to pass through the membrane to the cathode area to maintain the charge balance of the system. The driving force of this process comes from the ΔpH of the cathode and anode, and the termination of discharge is marked by ΔpH of 0.

[0034] After the discharge is completed, the anode region is filled with protons H + The continuous generation of CO3 2- / HCO3 -The solution is fed with CO2 desorbed from the cathode to convert it into HCO3 - The solution is circulated to the cathode for standby use; during the cathode discharge process, the desorbed CO2 is introduced, and the cathode solution is HCO3 when the discharge ends. - , adding a salt to the solution, wherein the salt includes a guanidine salt G;

[0035] Guanidine salt G makes part of HCO3 - Transformed into G-H2CO3 crystal precipitate, the filtered solution CO3 - The crystalline part is returned to the anode for standby use, while the crystallized part uses photothermal to drive CO2 desorption. The desorbed CO2 is returned to the cathode solution and the anode solution after the reaction for use, and the guanidine salt G is recovered for reuse. The regenerated anode and cathode solutions repeatedly construct the acid-base proton concentration difference ΔpH and then output electrical energy again.

[0036] The above cycle realizes the conversion of photothermal energy into electrical energy.

[0037] A CO2 thermosensitive crystallization photothermal regeneration power generation method, comprising:

[0038] Step 1: Use photothermal energy to drive the desorption of gas in the desorbent. The desorbed gas is cyclically absorbed at the anode and cathode to form a proton concentration difference, and the circulating H2 is used as a proton carrier as an electrode redox reactant. The redox reaction is constructed at the two electrodes of the battery respectively, and the electrochemical system of gas crystal salt thermal regeneration is used to realize the conversion of photothermal energy into electrical energy output.

[0039] In the second step, the spatial delocalization of the photothermal utilization and power generation modules is achieved through the desorption of the gas medium on the salt and the absorption in the battery anode liquid; at the same time, the heat source only acts on the gas desorption, so that the mode of thermoelectric conversion is transformed from utilizing the Seebeck effect based on the system temperature difference to a cyclic system utilizing the entropy change of the liquid-based system.

[0040] The beneficial effects of the present invention include:

[0041] (1) In the embodiment of the present invention, not only CO2 is used as a circulating medium, but also a desorption aid guanidine salt is innovatively used to combine with carbonate to produce crystals, which greatly reduces the heat energy required to drive CO2 desorption, adapts to low-energy-density photothermal energy, and realizes efficient photothermal conversion. This system avoids the inefficient secondary conversion of the traditional photothermal power generation "thermal energy-mechanical energy-electrical energy" model, and at the same time avoids the problem of strong coupling of material conductivity, thermal conductivity, and Seebeck coefficient in thermovoltaic power generation technology based on thermoelectric materials, which is difficult to independently control. In the technical solution of the present invention, the thermal conductivity, electrical conductivity and Seebeck coefficient of the system are decoupled from each other, so the comprehensive improvement of the performance of the thermoelectric system can be achieved by independently adjusting the solvent system, electrolyte, etc., so it has greater potential in photothermal power generation power and energy efficiency. In addition, the system can also achieve a new mode of photothermal energy synergistically capturing CO2 and outputting electrical energy by matching CO2 with different inlet concentrations.

[0042] (2) In the embodiment of the present invention, the carbonate-based guanidine salt with low water solubility can be easily precipitated and crystallized from the aqueous solution, so that the CO2 in the solid carbonate-based guanidine salt with small specific heat capacity is desorbed by photothermal drive. The desorbed CO2 is cyclically absorbed at the anode and cathode to form a proton concentration difference and the circulating H2 is used as a proton carrier as an electrode redox reactant, thereby constructing a redox reaction at the two electrodes of the battery, thereby realizing the conversion of thermal energy into electrical energy output.

[0043] First, the power generation module uses circulating H2 as the redox reactant. That is, the electrochemical hydrogen evolution reaction (HER) occurs at the cathode of the module, alkalizing the solution (2H2O+2e - →H2+2OH - ) is used for CO2 absorption; the module anode undergoes electrochemical hydrogen oxidation reaction (HOR), releasing protons to acidify the solution and neutralize the alkalinity of the anolyte (H2→2H + +2e - The battery uses the proton concentration difference (△pH) between the cathode and anode as the driving force, and the external connecting wires form an electronic circuit to achieve external discharge.

[0044] After the discharge is completed, the anode liquid enters the CO2 absorption tank to absorb saturated CO2 (CO3 2- +CO2+H2O→2HCO3 - ) and then pumped to the cathode area. After the cathode liquid and guanidine salt G crystallize, guanidine salt G from HCO3 - Grab a proton H + and combined with an HCO3 - G-H2CO3 crystals are formed and precipitated, and CO3 is regenerated through this process 2-The solution is transported to the anode area of ​​the power generation module for recycling. The precipitated G-H2CO3 crystals are transported to the CO2 desorption tank, where they are heated and mixed by photothermal energy to release CO2. The released CO2 can be transported to the CO2 buffer tank for short-term storage, and then divided into two streams, which are respectively passed into the CO2 absorption tank (i.e., the anode liquid buffer tank) for regeneration of the cathode raw liquid and into the cathode area for acidification of the cathode liquid to lower the pH value. The remaining guanidine salt after desorbing CO2 is recycled back to the cathode liquid for use.

[0045] The above process fully realizes the conversion of solar thermal energy into electrical energy, and can be adapted to different heat sources to achieve efficient power generation. In addition, the system can also be applied to CO2 of varying concentrations, realizing the integration of CO2 capture and thermal power generation. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0047] Figure 1 This is a schematic diagram of the power generation system for the CO2 thermosensitive crystallization photothermal regeneration of the present invention;

[0048] Figure 2 This is a schematic diagram of the structure of the power generation system for the CO2 thermosensitive crystallization photothermal regeneration of the present invention;

[0049] Figure 3 This is the power generation curve of the system using NaHCO3 hydrogen cycle reaction;

[0050] Figure 4 This is a long-term stable power generation curve diagram of the system using NaHCO3 hydrogen cycle reaction;

[0051] Figure 5 is the CO2 absorption concentration curve of the solution;

[0052] Figure 6 is the G-H2CO3 desorption flow curve;

[0053] Figure 7 This is the power generation curve of the system using NaHCO3 hydrogen cycle reaction;

[0054] Figure 8 This is the power generation curve of the system using NaHCO3 as reactant;

[0055] In the figure, 1-battery anode gas chamber; 2-battery anode; 3-battery anode area; 4-cation exchange membrane; 5-battery cathode area; 6-battery cathode; 7-battery cathode gas chamber; 8-battery system; 9-load; 10-CO2 desorption tank; 11-CO2 buffer tank; 12-CO2 absorption tank. DETAILED DESCRIPTION

[0056] All features disclosed in all embodiments in this specification, or steps in all methods or processes implicitly disclosed, except for mutually exclusive features and / or steps, can be combined and / or expanded or replaced in any manner.

[0057] The embodiments of the present invention, more specifically, propose an electrochemical CO2 thermosensitive crystallization photothermal regeneration power generation system and method based on a guanidine salt-CO2 crystallization thermosensitive cycle. In the inventive concept, a carbonate-based guanidine salt with low water solubility is easily precipitated and crystallized from an aqueous solution, and photothermal drive can be used to desorb CO2 from a solid carbonate-based guanidine salt with a small specific heat capacity (wherein the guanidine salt is circulated as a desorbent), and the desorbed CO2 is cyclically absorbed at the anode and cathode to form a proton concentration difference and the circulating H2 is used as a proton carrier as an electrode redox reactant, respectively constructing a redox reaction at the two poles of the battery, and utilizing the electrochemical system of the CO2 crystallization guanidine salt thermosensitive regeneration to realize the conversion of photothermal energy into electrical energy output. Through the desorption of the CO2 medium on the guanidine salt G and its absorption in the battery anode liquid, the spatial delocalization of the photothermal utilization and power generation module is achieved, avoiding the problem of multi-factor coupling that is difficult to control in the thermoelectric conversion system. At the same time, the heat source only acts on CO2 desorption, so that the thermoelectric conversion mode is transformed from the Seebeck effect based on the system temperature difference to a circulation system that utilizes the entropy change of the liquid-based system, so that the system technology method can also have a good thermoelectric conversion effect under medium and low temperature application conditions.

[0058] In one embodiment, a method for power generation by photothermal regeneration of CO2 thermosensitive crystals is provided, which utilizes the special properties of crystallization after the combination of guanidine salt and carbonate to drive the desorption of CO2 in solid crystals by photothermal means and circulate the absorption and regeneration in an alkaline absorbent, thereby forming a proton concentration difference potential at the anode and cathode of the system and discharging it externally, thereby realizing the conversion of photothermal energy into electrical energy.

[0059] First, a CO2 absorbent (such as sodium carbonate) is added to the anode area of ​​the system to increase the pH value of the solution. A cathode solute (such as sodium bicarbonate) is added to the cathode area and CO2 is continuously introduced to maintain the pH value. The anode and cathode of the system are separated by a cation exchange membrane. At this time, a potential difference is generated due to the proton concentration difference (ΔpH) between the anode and cathode of the system. In addition, in this system, circulating hydrogen is used as a mass-electrode coupling agent to construct a redox couple and a proton carrier. The anode undergoes an H2 oxidation reaction (HOR), losing electrons and releasing protons (H +), acidifying the solution and neutralizing the alkalinity of the anode area; the cathode undergoes hydrogen evolution reaction (HER) to obtain electrons and extract H from the solution + , alkalize the solution, and the generated H2 can be passed into the anode for recycling. During the discharge process, the cation exchange membrane separates the cathode and cathode and allows the cations in the anode area to pass through the membrane to the cathode area to maintain the charge balance of the system. The driving force of this process comes from the ΔpH of the cathode and cathode, so the sign of discharge termination is ΔpH 0. After the discharge is completed, the anode area is filled with protons (H + ) is continuously generated, eventually forming CO3 2- / HCO3 - The solution is passed into the cathode desorbed CO2 to convert it into HCO3 - The solution is circulated to the cathode for use. Since the CO2 desorbed thereafter is continuously introduced during the cathode discharge process, the cathode solution is HCO3 at the end of the discharge. - Adding an appropriate amount of guanidine salt (G) to the solution can make part of the HCO3 - Transformed into G-H2CO3 crystal precipitate, the filtered solution (CO3 - ) is returned to the anode for future use, while the crystallized portion can be desorbed using low-grade solar heat. The desorbed CO2 is returned to the cathode solution and the anode solution after the reaction, while the guanidine salt G is recovered for reuse. The regenerated anode and cathode solutions repeatedly establish the acid-base proton concentration difference (ΔpH) and can output electricity again.

[0060] The above cycle realizes the conversion of photothermal energy into electrical energy.

[0061] In another embodiment, the present invention provides a power generation system based on CO2 thermosensitive crystallization and photothermal regeneration, the overall system structure of which mainly includes: a power generation module, a guanidine salt-CO2 crystallization and thermosensitive regeneration module, and a fluid circulation module. Among them, the power generation module uses a carbonate solution at the anode and a bicarbonate solution at the cathode (other solvents, CO2 alkaline absorbents and supporting electrolytes can also be used). Circulating H2 is used as the redox reactant. By using the proton concentration difference (△pH) between the cathode and anode as the driving force, external connecting wires form an electronic circuit to achieve external discharge.

[0062] During the discharge process, the module anode undergoes an electrochemical hydrogen oxidation reaction (HOR), releasing protons to acidify the solution and neutralize the alkalinity of the anolyte (H2→2H + +2e - ), in this process part of CO3 2- Bound proton H + Formation of HCO3 - (CO3 2- +H + →HCO3 -); Electrochemical hydrogen evolution reaction (HER) occurs at the cathode of the module, alkalizing the solution (2H2O+2e - →H2↑+2OH - ) for CO2 absorption (OH - +CO2→HCO3 - ). When the discharge is terminated, the proton concentration difference (ΔpH) between the two poles is reduced to 0. During the discharge process of the module, the pH of the cathode liquid continues to increase as the discharge reaction proceeds, and is used to absorb CO2 and maintain a nearly constant low pH environment after absorption. The pH of the anode liquid continues to decrease as the discharge reaction proceeds. When the pH of the cathode and anode of the module is balanced, the theoretical voltage is 0, and the discharge stops. In the system of this embodiment, a cation exchange membrane is used to separate the cathode and anode regions of the battery, which can not only keep the cations migrating from the anode region to the cathode region during the discharge process to maintain the charge balance of the system, but also separate the cathode and anode solutions, ensure a directional pH gradient, and avoid discharge losses caused by the mixing of the anode and cathode solutions.

[0063] After discharge, the anolyte is transported to the CO2 absorption tank to absorb saturated CO2 and then regenerated and circulated to the cathode area as the cathode area raw material. The catholyte combines with the guanidine salt G to form a precipitate G-H2CO3, which is separated from the solution by sedimentation. The solution is regenerated and circulated to the anode area as the anode area raw material. The crystals are transported to the CO2 desorption tank for photothermal desorption of CO2, and the guanidine salt is regenerated and used. The CO2 is then passed into the CO2 absorption tank and the cathode area for recycling. Through the above cycle, the ΔpH of the battery cathode and anode is reconstructed and restored to the level before discharge, completing the cycle.

[0064] The system of this embodiment achieves spatial delocalization between the discharge system and the heat regeneration system, connecting them only through a fluid transport mechanism. This avoids the constraints of traditional thermoelectric systems where both the cold and hot ends of the electrodes must be integrated into the same power generation system space. The special crystallization reaction of the desorbent guanidine salt and carbonate allows the heat source to act only on the G-H2CO3 crystals, desorbing CO2 from them. This reduces heat energy loss and enables efficient photothermal conversion. It can also be used with a variety of different heat sources, all of which can achieve good power generation and circulation effects. Furthermore, the system of this embodiment can absorb CO2 at different concentrations and coordinate CO2 capture and output electrical energy. Figure 4 This is a long-term stable power generation curve of the system using NaHCO3 hydrogen circulation reaction.

[0065] In another embodiment, the present invention provides a power generation system based on CO2 thermosensitive crystallization photothermal regeneration, which is described below with reference to the accompanying drawings. This embodiment also provides a power generation system and method for CO2 thermosensitive crystallization photothermal regeneration, such as Figure 1 The load 9 is connected to the battery anode 2 and the battery cathode 6 of the battery system 8 and is used to receive and detect the electric energy output by the battery.

[0066] The battery anode gas chamber 1 is connected to the battery cathode gas chamber 7 through a flow channel to realize the battery's hydrogen circulation system. During the reaction process, a hydrogen evolution reaction occurs on the battery cathode 6 to decompose water to produce H2. The gas is transported to the anode area through a one-way pipeline. An electrochemical hydrogen oxidation reaction occurs on the battery anode 2, and H2 loses electrons to generate H + .

[0067] The battery anode region 3 and the battery cathode region 5 are separated by a cation exchange membrane 4. Electrochemical hydrogen oxidation reaction occurs on the battery anode 2 (such as a platinum electrode, platinum-plated nickel mesh, etc.), and H2 loses electrons to generate H + , which reduces the alkalinity of the anode area. Under the action of the electric field, the cations (such as Na + etc.) through the cation exchange membrane 4 to reach the cathode area 5 of the battery to ensure charge balance. The anode liquid after the reaction is CO3 2- / HCO3 - It enters the CO2 absorption tank (also the anode liquid buffer tank) to absorb the CO2 desorbed by photothermal desorption and convert it into HCO3 - Realize recycling and regeneration of HCO3 - The solution circulates to the cathode area as the cathode reaction raw material. The reaction equation is as follows:

[0068] Anode reaction: H2→2H + +2e -

[0069] Anode reaction: 2H + +2CO3 2- →2HCO3 -

[0070] CO2 absorption tank (anolyte buffer tank) reaction: CO3 2- +CO2+H2O→2HCO3 -

[0071] The battery cathode 6 is a hydrogen evolution electrode (such as a platinum electrode, platinum-plated nickel mesh, etc.), which undergoes an electrochemical reduction reaction to decompose water to produce H2 and OH. - , thereby increasing the alkalinity of the cathode liquid and being used to absorb the circulating CO2 desorbed by photothermal desorption to generate bicarbonate solution. The reaction equation is as follows:

[0072] Cathode reaction: 2H2O+2e - →H2+2OH -

[0073] Cathode zone reaction: 2OH - +2CO2→2HCO3 -

[0074] In the cathode area, guanidine salt G is recycled from the CO2 photothermal desorption tank and crystallizes with the cathode liquid after the reaction. Guanidine salt G is converted from HCO3 - Grab a proton H + and combined with an HCO3 - G-H2CO3 crystals are formed and precipitated, and the alkaline absorbent CO3 is regenerated through this process. 2- The solution is transported to the anode area of ​​the power generation module for recycling, and the remaining guanidine salt after desorbing CO2 is recycled back to the cathode area for use. - The crystallization reaction is as follows:

[0075] Guanidine-carbonic acid crystallization reaction: G+2HCO3 - →G-H2CO3↓+CO3 2-

[0076] The G-H2CO3 crystals precipitated from the cathode liquid are transported to the CO2 desorption tank 10, where they are heated and mixed by photothermal energy to release CO2. The released CO2 can be transported to the CO2 buffer tank 11 for short-term storage, and then divided into two streams, which are respectively fed into the CO2 absorption tank 12 (i.e., the anode liquid buffer tank) for regeneration of the cathode raw liquid and fed into the cathode area for acidification of the cathode liquid to reduce the pH value. The reaction formula is as follows:

[0077] CO2 desorption tank reaction: G-H2CO3→G+H2O+CO2↑

[0078] CO2 is desorbed and released under low energy density photothermal conditions, and the guanidine salt G is recycled.

[0079] The system of this embodiment can realize the stable output of converting photothermal energy into electrical energy through hydrogen circulation reaction, guanidine salt-CO2 crystallization thermal regeneration cycle and fluid pumping cycle.

[0080] In other embodiments, including but not limited to the following transformations:

[0081] The electrode reactions used in the present invention are hydrogen evolution reaction (HER) and hydrogen oxidation reaction (HOR), which can also be replaced by oxygen evolution reaction (OER) and oxygen reduction reaction (ORR), or other electrochemical reactions accompanied by protons (H + ) transfer reactions, such as MnOOH, quinone, phenazine, and alloxazine.

[0082] The CO2 absorbent used in the present invention is a carbonate solution, which can be adapted to different types of cations, including but not limited to: KOH, NaOH, ammonia water, monoethanolamine, ethylenediamine, triethanolamine, piperazine, etc.

[0083] The present invention can also use other - 、CO32- The desorption aid that produces precipitated crystals is used as a CO2 desorption carrier for thermal regeneration cycle, including but not limited to guanidine salts.

[0084] The system assembly method adopted by the present invention is not only applicable to regular shapes, but can also be replaced with special shapes in the future to adapt to different environments. The power generation module can be a two-chamber structure or a multi-chamber structure.

[0085] This invention is primarily targeted at low-grade solar thermal power generation, but can also be used for high-grade thermal power generation (>150°C), adapting to a variety of heat sources. The system can utilize pure CO2 gas as well as impure CO2 sources, such as factory flue gas and atmospheric CO2, to achieve integrated CO2 capture and thermal power generation.

[0086] Different from the previous CO2 thermal regeneration or NH3 thermal regeneration cycle batteries, the present invention uses guanidine salts and carbonates to produce low specific heat capacity crystals, which greatly reduces the required heat source temperature (solid-base desorption) and avoids the heat loss caused by heating additional large specific heat capacity liquids, making it applicable to low energy density photothermal systems.

[0087] Although the cyclic H2 reaction used in the present invention is also used in liquid flow battery systems or acid-base neutralization energy generation systems in the field of energy storage, or in electrolysis systems. However, the driving force and background significance of such systems are completely different from those used in the present invention. For example: Liquid flow batteries, as energy storage batteries, are mainly used to solve the volatility of renewable electricity (such as wind power, photovoltaics, etc.) and store electricity. Battery discharge can only be achieved after charging, and energy loss will occur during the charge and discharge cycle. This type of battery cannot use thermal energy as a driving force (especially low-grade waste heat) to achieve battery discharge, and its technical purpose and field are completely different from the present invention.

[0088] Acid-base neutralization batteries, such as acid-base concentration batteries and CO2 mineralization batteries, utilize the pH difference between the two electrodes to create a potential difference. However, the principle behind this pH difference is completely different from the present invention. These batteries consume large amounts of acidic and alkaline substances. Their purpose is to process and recycle industrial waste acid (or acidic gases such as CO2) and waste alkali, completely failing to utilize heat as a driving force for waste heat power generation. Furthermore, the consumable acid and alkali can lead to the loss of reaction raw materials, making the process irreversible.

[0089] Electrochemical electrolysis systems, on the other hand, are a purely electrical energy-consuming process, fundamentally different from battery-generated power systems that export energy. These systems are primarily focused on chemical production, consuming electricity to produce economically valuable chemical products. They are unable to efficiently recover low-grade thermal energy and achieve net energy output.

[0090] The advantages of the present invention are further described as follows:

[0091] 1. The system constructs H2 as a mass-to-electrochemical coupling agent, which achieves electron gain and loss through its own oxidation reaction at the anode and reduction reaction at the cathode, thereby outputting electrical energy. During the entire process, H2 can be completely circulated without additional replenishment, avoiding the use of consumable electrodes in traditional batteries. In addition, the redox reaction carrier of the system can also be replaced by other mass-to-electrochemical coupling agents. For example, the available organic PCET reactants include but are not limited to phenazine, alloxazine, quinone and its derivatives. The organic PCET reactant at the battery anode undergoes an electrochemical oxidation reaction, releasing H + The acidified solution reduces the alkalinity of the anolyte; the organic PCET reactants at the cathode of the battery undergo electrochemical reduction reaction, receiving H + Alkalinizing the solution increases the alkalinity of the cathode liquid.

[0092] 2. The driving force of the power generation module of this system comes from the proton concentration difference (ΔpH) between the cathode and anode, which is constructed by CO2 absorption and thermal desorption. The cathode and anode electrolytes of this system mainly include three parts: solvent, CO2 alkaline absorbent and supporting electrolyte. Commonly used solvents are mainly water, and organic solvents can also be used, including but not limited to: alcohol solvents, ether solvents and ester solvents. CO2 alkaline absorbent can provide an alkaline environment for the solution. Commonly used CO2 alkaline absorbents include but are not limited to: (NH4)2CO3, KOH, NaOH, ammonia water, monoethanolamine, ethylenediamine, triethanolamine, piperazine, etc. The supporting electrolyte can provide high ionic conductivity for the battery system, and conventional salt supporting electrolytes or ionic liquids can be used.

[0093] 3. This system typically uses carbon-based materials as electrodes. Common carbon-based material matrices include, but are not limited to, graphite felt, carbon paper, carbon cloth, carbon rods, and carbon sheets. Electrode materials can also be modified using metal electrode substrates or metal catalysts. Common metal electrode substrates include, but are not limited to, nickel foam, platinum sheets, and nickel-plated platinum mesh. Common catalytic supports include, but are not limited to, Pt / C and Pd / C. Furthermore, noble metals can be directly used as electrode materials within this system to minimize charge transfer overpotential and effectively catalyze rapid electron transfer, thereby increasing the maximum power density of the battery.

[0094] 4. The power generation module and heat regeneration module of this system are completely spatially delocalized, and each part is connected by a fluid transport mechanism. This avoids the constraint that the cold and hot ends of the electrodes in the traditional thermoelectric system must be integrated into the same power generation system space. After the battery is discharged, the desorption aid guanidine salt G is added to the cathode liquid to precipitate some HCO3 -. The solution phase is transported to the anode area as raw material. The solid phase G-H2CO3 crystals are used for photothermal desorption. Since the specific heat capacity of the solid is smaller, the utilization rate of thermal energy is significantly improved. The solid guanidine salt G after desorption is returned for recycling. Part of the desorbed CO2 is used for absorption and regeneration of the anode liquid after the reaction and transported to the cathode area as raw material. Thereby, a new △pH driving force is constructed to restore the system to the state before discharge, completing the cyclic sustainable discharge of the system. Another part of the CO2 is transported to the cathode area to maintain the cathode pH environment.

[0095] 5. This system combines the special crystallization reaction of guanidine salt and carbonate as desorption aids so that the heat source only acts on G-H2CO3 crystals to desorb CO2, avoiding the large amount of heat energy wasted due to the large specific heat capacity of the solution. Reducing heat energy loss can achieve efficient photothermal conversion. At the same time, due to the small specific heat capacity of solid G-H2CO3 crystals, it is easy to heat and desorb CO2. Therefore, the system can match a variety of different heat sources, all of which can achieve good power generation and circulation effects. In addition, the system can also use other heat sources that can react with CO2, HCO3 - 、CO3 2- The desorption aid that produces precipitation crystals is used as a CO2 desorption carrier for thermal regeneration cycle, including but not limited to guanidine salt, whose structure is as follows:

[0096]

[0097] 6. At the same time, this system can absorb CO2 of different concentrations and capture CO2 to output electrical energy.

[0098] 7. The entire system can be designed as a simple integrated device according to needs, or it can be designed into a large-scale integrated device through system series and parallel connection, and can match a variety of heat source scenarios in addition to medium and high temperature geothermal energy.

[0099] Example 1

[0100] In another embodiment, the raw materials and sources used in the following embodiments are as follows: analytically pure sodium carbonate and sodium bicarbonate are directly used as power generation raw materials, and guanidine salt PyBIG is used as a CO2 desorption aid. The cation exchange membrane in the following embodiments can be Nafion115 membrane (DuPont). The system structure of this embodiment is as follows Figure 2 As shown, the process is as Figure 1 shown.

[0101] This embodiment provides a CO2 thermosensitive crystallization photothermal regeneration power generation system, which includes an electrolytic cell and a battery anode area 3 and a battery cathode area 5 on both sides of the electrolytic cell, wherein the battery anode area 3 and the battery cathode area 5 are separated by a cation exchange membrane 4, an alkaline absorbent Na2CO3 solution is added to the battery anode area 3, and a NaHCO3 solution is added to the battery cathode area 5. During the power generation process, CO2 is continuously introduced into the cathode, and a load 9 is connected between the battery anode 2 and the battery cathode 6. The system also includes a CO2 desorption tank 10, a CO2 buffer tank 11, and a CO2 absorption tank (i.e., an anode liquid buffer tank) 12. The various parts are connected by a pumping system, and the thermal-electrical spatial delocalization and recycling of the entire system are achieved through the crystallization reaction of guanidine salt-G and CO2, G-H2CO3 photothermal desorption, and CO2 absorption regeneration. In this embodiment, the effective area in the electrolytic cell is 4cm 2 The electrolytic cell has a catalyst in the reduction tower that is nickel-plated platinum mesh.

[0102] The specific operation steps are as follows: 50mL of 1mol / L Na2CO3 solution is added to the anode region as the anolyte, and 50mL of 1mol / L NaHCO3 solution is added to the cathode region as the catholyte. CO2 is continuously introduced into the anode to maintain pH. The proton concentration difference (ΔpH) between the anode and cathode solutions is the driving force for the system's discharge. A pump circulates at a flow rate of 20mL / min between the electrolyzer and the storage tank, and H2 is introduced to the cell anode 2 through the cell anode gas chamber 1 at a flow rate of 20mL / min. A load 9 is connected to the cell anode 2 and the cell cathode 6 of the thermoelectrochemical cell system 8 to receive and detect the electrical energy output by the cell.

[0103] Both the anode and cathode are carbon-based electrodes (such as graphite felt, carbon paper, carbon cloth, platinum electrode, platinum-plated nickel mesh, etc.). During the reaction, hydrogen evolution reaction occurs on the battery cathode 6 to decompose water to produce H2 and OH-, and the increased alkalinity is used to absorb CO2 to generate HCO3. - The H2 generated at the cathode is transported to the battery anode gas chamber 1 through a one-way pipe, where an electrochemical hydrogen oxidation reaction occurs on the battery anode 2, and H2 loses electrons to generate H + Acidify the anolyte. The difference in proton concentration (ΔpH) between the anode and cathode regions is the driving force for battery discharge. When discharge ends, the pH values ​​at both electrodes are equal. The battery's anode gas chamber 1 and cathode gas chamber 7 are connected by flow channels, completing the battery's hydrogen circulation system.

[0104] The battery anode region 3 and the battery cathode region 5 are separated by a cation exchange membrane 4. Electrochemical hydrogen oxidation reaction occurs on the battery anode 2 (such as a platinum electrode, platinum-plated nickel mesh, etc.), and H2 loses electrons to generate H + , which reduces the alkalinity of the battery anode area 2. Under the action of the electric field, the cations in the battery anode area 3 (such as Na +etc.) through the cation exchange membrane 4 to reach the battery cathode region 5. The battery reaction equation is as follows:

[0105] Anode reaction: H2→2H + +2e -

[0106] Anode reaction: 2H + +2CO3 2- →2HCO3 -

[0107] Cathode reaction: 2H2O+2e - →H2+2OH -

[0108] Cathode zone reaction: 2OH - +2CO2→2HCO3 -

[0109] After the discharge is terminated, the cathode liquid reacts with the guanidine salt G to form a guanidine salt-CO2 crystallization reaction. The supernatant is returned to the anode area for regeneration. The crystal precipitate enters the CO2 desorption tank 10, where CO2 is desorbed from the G-H2CO3 under the drive of light and heat energy. The desorbed CO2 enters the CO2 buffer tank for temporary storage, and the guanidine salt G returns to the cathode area for recycling. Part of the CO2 in the CO2 buffer tank flows into the CO2 absorption tank (i.e., the anode liquid buffer tank) and neutralizes the CO3 2- The alkalinity of the ions allows them to be transported to the cathode area for regeneration, while the other part is continuously fed into the cathode area to maintain the pH value of the cathode area. The reactions are as follows:

[0110] Guanidine-CO2 crystallization reaction: G+2HCO3 - →G-H2CO3↓+CO3 2-

[0111] G-H2CO3 decomposition reaction: G-H2CO3→CO2↑+G+H2O

[0112] The system can convert thermal energy into stable electrical energy output through hydrogen circulation reaction, CO2 crystallization thermal regeneration cycle and fluid pumping cycle.

[0113] The results show that: using the system of the above embodiment, the load output current program is to increase by 0.005A per second until the voltage drops to 0V and stops. Initially, the load output function is not turned on, and the load displays the open circuit voltage. It will increase from 0V until the open circuit voltage increases to 0.85V and then stop increasing. When the output button is turned on, the current will continue to increase. As the voltage continues to decrease, the output stops when the voltage drops to 0V. After processing the data, it can be obtained that the maximum power density of this process is 102.55W / m 2 (like Figure 3 ).

[0114] Example 2

[0115] Based on the above technical solution, this example is a CO2 absorption and G-H2CO3 desorption CO2 test to prove the cyclic effect of CO2 in the whole system and that guanidine salt G can be used as a good carrier for CO2 photothermal desorption. 50mL of Na2CO3 solution with a concentration of 0.5mol / L was prepared and saturated by CO2 absorption to obtain its CO2 absorption flow curve. The G-H2CO3 crystals precipitated by the reaction were heated by light to obtain the CO2 desorption concentration curve. The absorption and desorption curve is as follows: Figure 5 、 Figure 6 shown.

[0116] Comparative Example 1

[0117] The operation process of this comparative example is basically the same as that of Example 1, with the only difference being that in this comparative example, 50 mL of 1 mol / L Na2CO3 anolyte is added to the anode region, 50 mL of 1 mol / L NaHCO3 is added to the cathode region as the cathode solution, and CO2 is continuously introduced at the cathode to maintain a relatively stable pH value. A pump is used to circulate the solution between the electrolytic cell device, the storage tank, and the reduction tower at a flow rate of 20 mL / min, and H2 is introduced into the anode region through the battery cathode gas chamber at a flow rate of 20 mL / min, and a load is placed between the anode electrode and the cathode electrode. After the reaction is completed, the CO2 thermal desorption-absorption cycle regeneration process of the bipolar solution is not carried out, and the power generation is tested. The voltage during the discharge process is always 0 V (such as Figure 7 ), it is impossible to generate electricity, which means that it cannot continue to discharge without heating after the reaction.

[0118] Comparative Example 2

[0119] The operation process of this comparative example is basically the same as that of Example 1, with the only difference being that in this comparative example, 50 mL of 1 mol / L Na2CO3 anolyte is added to the anode region, 50 mL of 1 mol / L NaHCO3 is added to the cathode region as the cathode liquid, and CO2 is continuously introduced into the cathode to maintain a relatively stable pH value. A pump is used to circulate the solution between the electrolytic cell device, the storage tank, and the reduction tower at a flow rate of 20 mL / min, without introducing H2 into the anode region, and a load is placed between the anode electrode and the cathode electrode. The power generation is tested, and there is an open circuit voltage but no current (such as Figure 8 ), unable to generate electricity, indicating the importance of H2 adaptation to the battery system.

[0120] The above examples are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. It should be noted that those skilled in the art may make various improvements and modifications based on the technical solution and inventive concept of the present invention without departing from the principles of the present invention, and such improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A CO2 thermosensitive crystallization photothermal regeneration power generation system, characterized in that: include: A load (9), a battery system (8), a CO2 desorption tank (10), a CO2 buffer tank (11) and a CO2 absorption tank (12), wherein the battery system (8) comprises a battery anode gas chamber (1), a battery anode (2), a battery anode region (3), a cation exchange membrane (4), a battery cathode region (5), a battery cathode (6), a battery cathode gas chamber (7) and a battery system (8); The load (9) is connected to the battery anode (2) and the battery cathode (6) of the battery system (8) for receiving and detecting the electric energy output by the battery; the battery anode gas chamber (1) is connected to the battery cathode gas chamber (7) flow channel for realizing the hydrogen circulation system of the battery; During the reaction, a hydrogen evolution reaction occurs on the battery cathode (6) to decompose water and produce H2. The gas is transported to the anode area through a one-way pipe, and an electrochemical hydrogen oxidation reaction occurs on the battery anode (2). H2 loses electrons to generate H + ; The battery anode region (3) and the battery cathode region (5) are separated by a cation exchange membrane (4). Electrochemical hydrogen oxidation reaction occurs on the battery anode (2), and H2 loses electrons to generate H + , so that the alkalinity of the anode area is reduced; under the action of the electric field, the cations in the battery anode area (3) pass through the cation exchange membrane (4) to reach the battery cathode area (5), ensuring charge balance; The anolyte after the reaction is CO3 2- / HCO3 - , it enters the CO2 absorption tank (12) to absorb the CO2 desorbed by photothermal desorption and converts it into HCO3 - Realize recycling and regeneration of HCO3 - The solution circulates to the cathode area as cathode reaction raw material. The reaction equation is as follows: Anode reaction: H2→2H + +2e - Anode reaction: 2H + +2CO3 2- →2HCO3 - CO2 absorption tank reaction: CO3 2- +CO2+H2O→2HCO3 - The battery cathode (6) is a hydrogen evolution electrode, which undergoes electrochemical reduction reaction to decompose water to produce H2 and OH - , thereby increasing the alkalinity of the cathode liquid and being used to absorb the circulating CO2 desorbed by photothermal desorption to generate bicarbonate solution. The reaction equation is as follows: Cathode reaction: 2H2O+2e - →H2+2OH - Cathode zone reaction: 2OH - +2CO2→2HCO3 - In the cathode zone, salts recycled from the CO2 photothermal desorption tank are crystallized with the cathode liquid after the reaction, and the salts include guanidine salt G; Guanidine salt G from HCO3 - Grab a proton H + and combined with an HCO3 - G-H2CO3 crystals are formed and precipitated, and the alkaline absorbent CO3 is regenerated through this process. 2- The solution is transported to the anode area for recycling, and the remaining guanidine salt after desorption of CO2 is recycled back to the cathode area for use; the guanidine salt G and HCO3 - The crystallization reaction is as follows: Guanidine-carbonic acid crystallization reaction: G+2HCO3 - →G-H2CO3↓+CO3 2- The G-H2CO3 crystals precipitated from the cathode liquid are transported to the CO2 desorption tank (10), where they are heated and mixed by photothermal energy to release CO2. The released CO2 is transported to the CO2 buffer tank (11) for short-term storage, and then divided into two streams and respectively introduced into the CO2 absorption tank (12) for regeneration of the cathode raw liquid and introduced into the cathode area for acidification of the cathode liquid to reduce the pH value. The reaction formula is as follows: CO2 desorption tank reaction: G-H2CO3→G+H2O+CO2↑ CO2 is desorbed and released under light and heat, and the guanidine salt G is recycled.

2. The CO2 thermosensitive crystallization photothermal regeneration power generation system according to claim 1 is characterized in that: The battery anode (2) comprises a platinum electrode and a platinum-plated nickel mesh.

3. The CO2 thermosensitive crystallization photothermal regeneration power generation system according to claim 1 is characterized in that: The CO2 absorption tank (12) also serves as an anode liquid buffer tank.

4. The CO2 thermosensitive crystallization photothermal regeneration power generation system according to claim 1 is characterized in that: The battery cathode (6) comprises a platinum electrode and a platinum-plated nickel mesh.

5. A CO2 thermosensitive crystallization photothermal regeneration power generation system, characterized in that: The carbonate solution in the CO2 thermosensitive crystallization photothermal regeneration power generation system described in any one of claims 1 to 4 is used as a CO2 absorbent to adapt to different types of cations, wherein the carbonate solution can be replaced by any one of KOH, NaOH, ammonia water, monoethanolamine, ethylenediamine, triethanolamine, and piperazine.

6. A CO2 thermosensitive crystallization photothermal regeneration power generation system, characterized in that: The electrode reactions used in the CO2 thermosensitive crystallization photothermal regeneration power generation system according to any one of claims 1 to 4 are hydrogen evolution reaction HER and hydrogen oxidation reaction HOR, and the hydrogen evolution reaction HER and hydrogen oxidation reaction HOR can be replaced by oxygen evolution reaction OER and oxygen reduction reaction ORR.

7. A CO2 thermosensitive crystallization photothermal regeneration power generation system, characterized in that: The electrode reaction used in the CO2 thermosensitive crystal photothermal regeneration power generation system according to any one of claims 1 to 4 can be replaced by a proton H + Any electrochemical reaction that transfers.

8. A method for power generation by photothermal regeneration of CO2 thermosensitive crystals, characterized in that: The CO2 thermosensitive crystal photothermal regeneration power generation system according to claim 1 converts photothermal energy into stable electrical energy output through hydrogen circulation reaction, guanidine salt-CO2 crystal photothermal regeneration cycle and fluid pumping cycle, and specifically includes the following sub-steps: By utilizing the crystallization properties of guanidine salts after combining with carbonates, photothermal energy is used to drive the desorption of CO2 from the carbonate-based guanidine salt solid crystals and circulate the absorption and regeneration in the alkaline absorbent, thereby forming a proton concentration difference potential at the anode and cathode of the system and discharging it to the outside, thereby realizing the conversion of photothermal energy into electrical energy.

9. The method for power generation by photothermal regeneration of CO2 thermosensitive crystals according to claim 8, characterized in that: The method utilizes the crystallization property of guanidine salt combined with carbonate to desorb CO2 in the solid crystal driven by light and heat and regenerate it in an alkaline absorbent, thereby forming a proton concentration difference potential at the anode and cathode of the system and discharging it externally, thereby realizing the conversion of light and heat energy into electrical energy. The method specifically includes the following sub-steps: First, a CO2 absorbent is added to the anode region to increase the pH value of the solution, and a cathode solute is added to the cathode region and CO2 is introduced to maintain the pH value. The anode and cathode of the system are separated by a cation exchange membrane. At this time, there is a proton concentration difference ΔpH between the anode and cathode of the system, which generates a potential difference. In addition, by circulating hydrogen as a mass-electrode coupling agent to construct a redox couple and a proton carrier, the anode undergoes an H2 oxidation reaction HOR, which loses electrons and releases protons H + , acidifying the solution and neutralizing the alkalinity of the anode area; The hydrogen evolution reaction (HER) occurs at the cathode, which obtains electrons and extracts H from the solution. + , alkalize the solution, and the generated H2 is then passed into the anode for recycling. During the discharge process, the cation exchange membrane separates the cathode and anode and allows cations in the anode area to pass through the membrane to the cathode area to maintain the charge balance of the system. The driving force of this process comes from the ΔpH of the cathode and anode, and the termination of discharge is marked by ΔpH of 0. After the discharge is completed, the anode region is filled with protons H + The continuous generation of CO3 2- / HCO3 - The solution is fed with CO2 desorbed from the cathode to convert it into HCO3 - The solution is circulated to the cathode for use; During the cathode discharge process, the desorbed CO2 is introduced, and the cathode solution is HCO3 when the discharge ends. - , adding a salt to the solution, wherein the salt includes a guanidine salt G; Guanidine salt G makes part of HCO3 - Transformed into G-H2CO3 crystal precipitate, the filtered solution CO3 - The crystalline part is returned to the anode for standby use, while the crystallized part uses photothermal to drive CO2 desorption. The desorbed CO2 is returned to the cathode solution and the anode solution after the reaction for use, and the guanidine salt G is recovered for reuse. The regenerated anode and cathode solutions repeatedly construct the acid-base proton concentration difference ΔpH and then output electrical energy again. The above cycle realizes the conversion of photothermal energy into electrical energy.

10. A method for power generation by photothermal regeneration of CO2 thermosensitive crystals, characterized in that: The power generation system based on the CO2 thermosensitive crystallization photothermal regeneration according to claim 1 comprises: Step 1: Use photothermal energy to drive the desorption of gas in the desorbent. The desorbed gas is cyclically absorbed at the anode and cathode to form a proton concentration difference, and the circulating H2 is used as a proton carrier as an electrode redox reactant. The redox reaction is constructed at the two electrodes of the battery respectively, and the electrochemical system of gas crystal salt thermal regeneration is used to realize the conversion of photothermal energy into electrical energy output. In the second step, the spatial delocalization of the photothermal utilization and power generation modules is achieved through the desorption of the gas medium on the salt and the absorption in the battery anode liquid; at the same time, the heat source only acts on the gas desorption, so that the mode of thermoelectric conversion is transformed from utilizing the Seebeck effect based on the system temperature difference to a cyclic system utilizing the entropy change of the liquid-based system.

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