Power generation system using potential difference caused by different solvents

Abstract

To achieve both of stable power supply, and decrease in carbon dioxide exhaust amount.SOLUTION: An electric potential difference formed by the difference in composition of solvent of electrolyte between a negative electrode 3 and a positive electrode 4 is used to generate an electric power. The solvent of the electrolyte of the negative electrode 3 and that of the positive electrode 4 are managed, whereby an exhaust of carbon dioxide is eliminated to keep power generation.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a power generation system using a potential difference caused by a difference in solvent composition between electrodes. Mu Regarding. [Background technology]

[0002] Reducing carbon dioxide emissions is an issue that must be addressed on a global scale, and in the field of power generation, there is a growing demand to move away from dependence on fossil fuels. For example, technology has been proposed that combines renewable energy power generation facilities with power generation facilities that use thermal energy such as geothermal energy (see, for example, Patent Document 1).

[0003] Carbon dioxide emissions are being reduced by using renewable energy power generation facilities, etc. In the field of power generation, the issue of achieving both a stable supply of electricity and a reduction in carbon dioxide emissions is currently being raised, and there is a current demand for the development of technology that can provide a stable supply of electricity without relying on fossil fuels. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2020-167798 Summary of the Invention [Problem to be solved by the invention]

[0005] The present invention has been made in view of the above circumstances, and provides a power generation system that utilizes the difference in solvent composition between electrodes, which can achieve both a stable supply of power and a reduction in carbon dioxide emissions. M The purpose is to provide. [Means for solving the problem]

[0006] To achieve the above object, the present invention provides a power generation system using a potential difference caused by different solvents, according to claim 1, comprising: a first tank containing an electrolytic solution of a first solvent, having one electrode, and causing an electrode reaction of an active material; and a second tank containing an electrolytic solution of a second solvent different from the electrolytic solution contained in the first tank, having the other electrode, and causing an electrode reaction of an active material; The electrode reaction caused by the active material in the first tank and the electrode reaction caused by the active material in the second tank are reverse reactions caused by the same redox pair. It is characterized by:

[0007] In the present invention according to claim 1, by selecting the first solvent as the electrolyte in the first tank and the second solvent as the electrolyte in the second tank according to the active material that undergoes an electrode reaction, it is possible to increase the potential difference formed between the electrodes compared to when the first solvent and the second solvent have the same composition. Furthermore, the first tank and the second tank can be separated by a solid electrolyte, a gel electrolyte, a porous body, or the like, in order to prevent mixing of the electrolyte in the first tank and the electrolyte in the second tank while ensuring ionic conductivity. The electrode reaction in the first tank and the electrode reaction in the second tank are reverse reactions of the same redox couple. For example, the hexacyanoferrate (II) ion ([Fe(CN) 6 ] 4- ), hexacyanoferrate(III) ion ([Fe(CN) 6 ] 3- ) can be used as the active material.

[0008] The first solvent and the second solvent may each be a solvent consisting of a single substance, or may each be a mixed solvent consisting of a plurality of substances. 。

[0011] Also, Claim 2 The power generation system of the present invention using the potential difference caused by different solvents is Claim 1 In the power generation system using the potential difference caused by different solvents described in the above, the first solvent and the second solvent contain at least one of the same substances.

[0012] Claim 2In the present invention, a case may be considered in which a mixed solvent of solvent A and solvent B is used as the first solvent, and solvent A is used as the second solvent. Also, a case may be considered in which both the first solvent and the second solvent are mixed solvents of solvent A and solvent B, and the mixing ratio of solvent A to solvent B differs between the first solvent and the second solvent. For example, water can be used as solvent A, and acetone can be used as solvent B.

[0013] Also, Claim 3 The power generation system of the present invention using the potential difference caused by different solvents is Claim 1 or Claim 2 In the power generation system using the potential difference caused by different solvents described in the above, the first solvent and the second solvent contain at least one of water, ethanol, methanol, acetonitrile, dimethyl sulfoxide, acetone, pyridine, dimethylacetamide, dimethylformamide, hexamethylphosphoramide, propylene carbonate, tetrahydrofuran, and N-methyl-2-pyrrolidone.

[0014] Claim 3 In the present invention related to the above, the first solvent and the second solvent can be specified and appropriately selected depending on the type of active material that undergoes an electrode reaction in the electrochemical device.

[0015] Also, Claim 4 The power generation system of the present invention using the potential difference caused by different solvents is Claim 1 or Claim 2 In the power generation system using the potential difference caused by different solvents described above, a salt having a melting point of 200°C or less at 1 atm is used in at least one of the first solvent and the second solvent.

[0016] Claim 4 In the present invention, salts having a melting point of 200° C. or less at 1 atm can be used as materials constituting the first solvent and the second solvent depending on the type of active material that undergoes an electrode reaction.

[0017] Also, Claim 5 The power generation system of the present invention using the potential difference caused by different solvents is Claims 1 to 4The power generation system using the potential difference caused by different solvents described in any one of the above is characterized by comprising a supply / discharge means for supplying an electrolyte solution from the outside into the first tank and the second tank, and discharging the electrolyte solution after (a part or all) of the active material has undergone an electrode reaction to the outside of the first tank and the second tank.

[0018] Claim 5 In the present invention, unused electrolyte is continuously supplied from the outside, thereby maintaining the difference in the composition of the solvents in the first tank and the second tank, thereby maintaining the potential difference of the power generation system and enabling continuous power generation.

[0019] Also, Claim 6 The power generation system of the present invention using the potential difference caused by different solvents is Claim 5 In the power generation system using the potential difference caused by different solvents described in 1), the first solvent and the second solvent are a mixture of solvent A and solvent B, and the first solvent contains a larger amount of solvent B than the second solvent, and the supply / discharge means supplies an electrolyte solution of the first solvent consisting of solvent A and solvent B from the outside to the first tank, discharges the electrolyte solution after an electrode reaction of the active material from the first tank, separates and recovers some or all of the solvent B from the discharged electrolyte solution, supplies the electrolyte solution after some or all of the solvent B has been separated to the second tank, discharges the electrolyte solution after an electrode reaction of the active material opposite to the electrode reaction in the first tank to the outside, re-mixes the separated and recovered solvent B with the discharged electrolyte solution, and supplies the electrolyte solution after the solvent B has been re-mixed to the first tank.

[0020] Claim 6In the present invention, the supply / discharge means is an electrolyte regeneration means that allows the electrolyte used in a reaction at one electrode to be reused in a reaction at the other electrode. Specifically, the electrolyte used in the electrode reaction in the first tank is used in the electrode reaction in the second tank after some or all of the solvent B has been separated. Also, the electrolyte used in the electrode reaction in the second tank is used again in the electrode reaction in the first tank after remixing with solvent B. Separation of solvent B can be achieved, for example, by externally inputting the thermal energy required to heat the electrolyte to above the boiling point of solvent B and the thermal energy required to vaporize solvent B. Alternatively, separation of solvent B can be achieved by pressurizing the electrolyte and externally inputting mechanical energy to separate solvent B due to a pressure difference.

[0021] That is, Claim 6 In the power generation system using the potential difference between different solvents, the electrode reaction in the second tank is the reverse reaction of the electrode reaction in the first tank, so there is no consumption of chemical substances overall, and power generation is continuous as the electrolyte circulates in the closed flow path. In addition, by storing the electrolyte after separation and remixing of solvent B, energy can be stored, allowing the amount of power generation to be controlled according to demand.

[0022] This power generation system is possible by inputting the thermal energy and mechanical energy required to separate solvent B. Therefore, by using heat sources such as waste heat, geothermal energy, hot spring heat, and solar heat for the input of thermal energy, and renewable energy such as wind, water, wave, and tidal power for the input of mechanical energy, a stable supply of electricity can be achieved without emitting carbon dioxide.

[0023] Also, Claim 7 The power generation system of the present invention using the potential difference caused by different solvents is Claim 6The power generation system using the potential difference caused by different solvents described in 2. above is characterized in that it has a second electrolytic solution regeneration means as a means for separating and recovering the solvent B from the electrolytic solution discharged from the first tank and supplying the electrolytic solution from which the solvent B has been separated to the second tank, and a first electrolytic solution regeneration means as a means for remixing the solvent B separated and recovered from the electrolytic solution discharged from the first tank with the electrolytic solution discharged from the second tank and supplying the electrolytic solution from which the solvent B has been remixed to the first tank.

[0024] Claim 7 In the present invention related to (1), the second electrolyte regeneration means separates and recovers solvent B from the electrolyte discharged from the first tank, and the electrolyte from which solvent B has been separated is supplied to the second tank. Then, the first electrolyte regeneration means remixes solvent B separated and recovered from the electrolyte discharged from the first tank with the electrolyte discharged from the second tank, and the electrolyte from which solvent B has been remixed is supplied to the first tank.

[0025] Also, Claim 8 The power generation system of the present invention using the potential difference caused by different solvents is Claim 7 In the power generation system using the potential difference caused by different solvents described above, the separation of solvent B in the first electrolyte regeneration means and the second electrolyte regeneration means and the remixing of solvent B are performed by means using thermal energy.

[0026] Claim 8 In the present invention, solvent B can be separated and remixed using thermal energy.

[0027] Also, Claim 9 The power generation system of the present invention using the potential difference caused by different solvents is Claim 8In the power generation system using the potential difference caused by different solvents described in 2. above, the means using thermal energy comprises an evaporation means that heats the electrolytic solution discharged from the first tank to evaporate the solvent B and supplies the electrolytic solution from which the solvent B has been separated to the second tank, and a condensation means that condenses the solvent B evaporated by the evaporation means, remixes the solvent B with the electrolytic solution discharged from the second tank, and supplies the mixture to the first tank.

[0028] Claim 9 In the present invention, the evaporating means heats the electrolytic solution discharged from the first tank to evaporate and separate the solvent B, and the electrolytic solution from which the solvent B has been separated is supplied to the second tank. The condensing means condenses the evaporated solvent B, and the condensed solvent B is remixed with the electrolytic solution discharged from the second tank and supplied to the first tank.

[0029] Also, Claim 10 The power generation system of the present invention using the potential difference caused by different solvents is Claim Item 8 or claim 9 The power generation system using the potential difference caused by different solvents described in the above is characterized by comprising an internal pressure adjusting means for adjusting the internal pressure of the electrolyte flow path in the supply / discharge means.

[0030] Claim 10 In the present invention, the boiling point of the solvent can be adjusted by pressurizing or depressurizing the electrolyte using the internal pressure adjusting means, and a heat source over a wide temperature range can be used for the electrolyte regenerating means serving as the supply and discharge means.

[0031] Also, Claim 11 The power generation system of the present invention using the potential difference caused by different solvents is Claim 7 In the power generation system using the potential difference caused by different solvents described above, the separation of solvent B in the first electrolyte regeneration means and the second electrolyte regeneration means and the remixing of solvent B are performed by means using mechanical energy.

[0032] Claim 11In the present invention, the separation of solvent B and the remixing of solvent B can be carried out using mechanical energy.

[0033] Also, Claim 12 The power generation system of the present invention using the potential difference caused by different solvents is Claim 11 In the power generation system using the potential difference caused by different solvents described in 1), the means using mechanical energy comprises a separation supply means that pressurizes the electrolytic solution discharged from the first tank and passes it through a separation means to separate the solvent B, and supplies the electrolytic solution from which the solvent B has been separated to the second tank, and a mixing supply means that remixes the solvent B that has passed through the separation means with the electrolytic solution discharged from the second tank and supplies the resultant to the first tank.

[0034] Claim 12 In the present invention, the separation supply means pressurizes the electrolytic solution discharged from the first tank and causes it to pass through the separation means to separate the solvent B, and the electrolytic solution from which the solvent B has been separated (is depressurized) is supplied to the second tank. Then, the mixing supply means remixes the electrolytic solution discharged from the second tank with the solvent B that has passed through the separation means, and supplies the mixture to the first tank.

[0035] In the power generation system using the potential difference caused by the different solvents described above, Electricity is generated using the potential difference formed by the difference in the composition of the electrolyte solvent between the positive and negative electrodes. It is a method of generating electricity.

[0036] This means: Electricity is generated by the potential difference formed by the difference in the composition of the electrolyte solvent between the positive and negative electrodes, making it possible to achieve both a stable supply of electricity and a reduction in carbon dioxide emissions. [Effects of the Invention]

[0037] The present invention Different solvents Electric potential difference power generation system M is This will make it possible to achieve both a stable supply of electricity and a reduction in carbon dioxide emissions. [Brief explanation of the drawings]

[0038] [Figure 1] 1 is a conceptual diagram of a power generation system according to the present invention. [Figure 2] FIG. 1 is a conceptual diagram of the solvation structure of the electrolyte in the first tank. [Figure 3] FIG. 1 is a conceptual diagram of the solvation structure of the electrolyte in the second tank. [Figure 4] FIG. 2 is a conceptual diagram of the molecular structures of a solvent and an active material. [Figure 5] FIG. 1 is a conceptual diagram of a power generation system of the present invention showing a solvent and an active material. [Figure 6] 1 is a graph showing the relationship between electromotive force and solvent B. [Figure 7] 1 is an overall configuration diagram of a power generation system according to a first embodiment of the present invention. [Figure 8] FIG. 10 is an overall configuration diagram of a power generation system according to a second embodiment of the present invention. [Figure 9] 1 is a graph showing changes in voltage over time. [Figure 10] FIG. 10 is an overall configuration diagram of a power generation system according to a third embodiment of the present invention. [Figure 11] FIG. 10 is an overall configuration diagram of a power generation system according to a fourth embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0039] An embodiment of a power generation system using a potential difference according to the present invention will be described with reference to FIGS. 1 to 6. FIG.

[0040] FIG. 1 shows a conceptual diagram of the overall configuration of the power generation system of the present invention, FIG. 2 shows a conceptual diagram illustrating the solvation structure of the electrolyte in the first tank, FIG. 3 shows a conceptual diagram illustrating the solvation structure of the electrolyte in the second tank, and FIG. 4(a) shows a conceptual diagram illustrating the active material, hexacyanoferrate (II) ion [Fe(CN)6]. 4- or hexacyanoferrate(III) ion [Fe(CN)6] 3-4(b) shows the concept of the molecular structure of water (HO), which is an example of solvent A (first solvent, second solvent), and Fig. 4(c) shows the concept of the molecular structure of acetone [(CH)CO], which is an example of solvent B (first solvent). Fig. 5 shows a conceptual overall configuration of the power generation system of the present invention, showing the solvents and active materials, and Fig. 6 shows a graph showing the relationship between electromotive force and solvent B.

[0041] As shown in Figure 1, the first active material (active material) is hexacyanoferrate (II) ion [Fe(CN)6]. 4- The system is equipped with a first tank 1 that contains a first solvent, which is a mixture of solvent A (water (HO)) and solvent B (acetone [(CH)CO]). The system also contains a second active material, hexacyanoferrate (III) ions [Fe(CN)]. 3- and solvent A (water (HO)). The first tank 1 and the second tank 2 are separated by a partition member such as a solid electrolyte, a gel electrolyte, or a porous body.

[0042] The second solvent is composed of solvent A and solvent B, but since the amount of solvent B is small, hereinafter the second solvent will be described as consisting of solvent A. In other words, the first solvent contains a larger amount of solvent B than the second solvent, and is a mixture of solvent A and solvent B.

[0043] A negative electrode (negative electrode) 3 is provided as one electrode in the first tank 1, and a positive electrode (positive electrode) 4 is provided as the other electrode in the second tank 2. The negative electrode 3 and the positive electrode 4 are connected to a power circuit (external circuit) 5, and a current flows in the power circuit 5 due to a potential difference formed by the difference in composition between the first solvent (solvent A + solvent B) in the first tank 1 and the second solvent (solvent A) in the second tank 2.

[0044] The first and second active materials may be of the same or different redox couples. Which of the electrodes in the first tank 1 and the second tank 2 serves as the positive electrode (negative electrode) depends on the type of active material, the types of solvents A and B, etc.

[0045] Hexacyanoferrate(II) ion [Fe(CN)6] 4- or hexacyanoferrate(III) ion [Fe(CN)6] 3- The second electrolyte solution (electrolyte solution Y) is made of solvent A (water (HO)), i.e., the hexacyanoferrate (II) ion [Fe(CN)6] dissolved in the second solvent made of solvent A (water (HO)). 4- or hexacyanoferrate(III) ion [Fe(CN)6] 3- The solvation structure of is shown in Figure 3. Note that the solvation structure shown in Figure 3 is an image, and the relative positions, number, and orientation of the solvent molecules (water) are arbitrary.

[0046] In addition, hexacyanoferrate(II) ion [Fe(CN)6] 4- or hexacyanoferrate(III) ion [Fe(CN)6] 3- The molecular structure of is shown in Figure 4(a), the molecular structure of water (H2O) is shown in Figure 4(b), and the molecular structure of acetone [(CH3)2CO] is shown in Figure 4(c).

[0047] That is, the negatively charged hexacyanoferrate ion ([Fe(CN)6] 4- , [Fe(CN)6] 3- reacts strongly with water (H2O) molecules, which have strong electron-accepting properties, to form a stable solvate structure.

[0048] Hexacyanoferrate(II) ion [Fe(CN)6] 4- or hexacyanoferrate(III) ion [Fe(CN)6] 3- The first electrolyte solution (electrolyte solution X) is a mixture of solvent A (water (HO)) and solvent B (acetone [(CH)CO]), i.e., the hexacyanoferrate (II) ion [Fe(CN)] dissolved in the first solvent mixture of solvent A (water (HO)) and solvent B (acetone [(CH)CO]). 4- or hexacyanoferrate(III) ion [Fe(CN)6] 3-The solvation structure of is shown in Figure 2. Note that the solvation structure shown in Figure 2 is an image, and the relative positions, number, and orientation of the solvent molecules (water, acetone) are arbitrary.

[0049] In other words, the stable solvation structure of water (HO) molecules changes when different solvents are mixed. For example, when acetone [(CH3)2CO], which has a weaker electron-accepting property than water (HO), is mixed, the hexacyanoferrate(II) ion ([Fe(CN)6]), which has a larger charge, is mixed. 4- will be relatively more affected and become unstable.

[0050] As shown in Figures 1 and 5, hexacyanoferrate (II) ions [Fe(CN)6] are added to the first tank 1. 4- is oxidized to form hexacyanoferrate(III) ion [Fe(CN)6] 3- In the second tank 2, hexacyanoferrate (III) ions [Fe(CN)6] 3- is reduced to form hexacyanoferrate(II) ion [Fe(CN)6] 4- Negative electrons (e - ) moves from the negative electrode 3 to the positive electrode 4, causing a current to flow in the power circuit 5.

[0051] That is, power is generated using the potential difference formed between the negative electrode 3 and the positive electrode 4. Because the first solvent (a mixture of solvent A and solvent B) and the second solvent (solvent A), which have different compositions, are used, a large potential difference is formed due to the difference in the solvent compositions, and power can be generated in the power circuit 5.

[0052] As shown in Figure 6, it has been confirmed that in electrolyte solution X, which is a mixture of solvent A (water (HO)) and solvent B (acetone [(CH)CO]), increasing the amount of solvent B (acetone [(CH)CO]) increases the electromotive force. Therefore, by appropriately selecting the amount of solvent B (acetone [(CH)CO]), any (desired) electromotive force can be generated.

[0053] Therefore, the active material (hexacyanoferrate (II) ion [Fe(CN)6] 4- , hexacyanoferrate(III) ion [Fe(CN)6] 3- By managing the first and second solvents, it is possible to maintain power generation without emitting carbon dioxide. The above-described power generation system makes it possible to achieve both a stable supply of power and a reduction in carbon dioxide emissions.

[0054] The first solvent and the second solvent can be selected to contain at least one of water, ethanol, methanol, acetonitrile, dimethyl sulfoxide, acetone, pyridine, dimethylacetamide, dimethylformamide, hexamethylphosphoramide, propylene carbonate, tetrahydrofuran, and N-methyl-2-pyrrolidone.

[0055] Furthermore, as a substance constituting the first solvent and the second solvent, a salt having a melting point of 200° C. or less at 1 atm can be used as appropriate.

[0056] A first embodiment of the present invention will be described with reference to Fig. 7. Fig. 7 shows the overall configuration of a power generation system according to the first embodiment of the present invention. Note that the same components as those in the power generation system shown in Fig. 1 are denoted by the same reference numerals.

[0057] In the power generation system shown in FIG. 7, first tank 1 contains electrolyte X consisting of a solvent and pre-reacted active material, and second tank 2 contains electrolyte Y consisting of a solvent and pre-reacted active material.

[0058] Electrolyte solution X containing the active material before reaction is supplied to the first tank 1 from the first tank 11 via a pump 12, and the electrolyte solution X after reaction is stored in a first recovery tank 13. Meanwhile, electrolyte solution Y containing the active material before reaction is supplied to the second tank 2 from a second tank 15 via a pump 16, and the electrolyte solution Y after reaction is stored in a second recovery tank 17. Reference numeral 19 in the figure denotes a temperature detection means for detecting the temperature of the electrolyte inside the first tank 11 and the second tank 15.

[0059] In the power generation system of the above-described embodiment, the active material and the first solvent (electrolyte solution X), and the active material and the second solvent (electrolyte solution Y) that undergo electrode reactions at the negative electrode 3 and the positive electrode 4 are appropriately selected so as to increase the electromotive force (so as to obtain a desired potential difference). The electrode reactions at the negative electrode 3 and the positive electrode 4 do not necessarily have to be reverse reactions caused by the same redox pair.

[0060] A second embodiment of the present invention will be described with reference to Figures 8 and 9. Figure 8 shows the overall configuration of a power generation system according to the second embodiment of the present invention, and Figure 9 shows the change in voltage over time. Note that the same components as those in the power generation system shown in Figure 1 are denoted by the same reference numerals. In the power generation system shown in Figure 8, the solvent of the electrolyte contained in the first tank 1 and the second tank 2 is the same as in the power generation system shown in Figure 1, and the active material is also the same as in the power generation system shown in Figure 1.

[0061] As shown in Figure 8, the active material, hexacyanoferrate (II) ion [Fe(CN)6] 4- The device is equipped with a first tank 1 containing an electrolyte solution X, which is a mixture of solvent A (water (HO)) and solvent B (acetone [(CH)CO]), containing the active material hexacyanoferrate (III) ion [Fe(CN)]. 3- The second tank 2 contains an electrolytic solution Y made of a solvent A (water (H2O)) having the above formula.

[0062] The active material, hexacyanoferrate (II) ion [Fe(CN)6] 4- , hexacyanoferrate(III) ion [Fe(CN)6] 3- Since not all of the reactants can react, electrolyte X contains [Fe(CN)6] 3- The electrolyte Y contains some [Fe(CN)6] 4- In addition, in the process of separating solvent B in the supply and discharge means described below, it may not be possible to separate all of solvent B, so that the electrolyte solution Y may contain some solvent B.

[0063] A negative electrode (negative electrode) 3 is provided in the first tank 1, and a positive electrode (positive electrode) 4 is provided in the second tank 2. The negative electrode 3 and the positive electrode 4 are connected to a power circuit (external circuit) 5, and a current flows in the power circuit 5 due to a potential difference caused by the difference in composition between the first solvent (solvent A + solvent B) in the first tank 1 and the second solvent (solvent A) in the second tank 2.

[0064] After the active material of electrolyte solution X consisting of solvent A and solvent B has completed the electrode reaction, an evaporator 21 is provided as a separation means for extracting electrolyte solution X from first tank 1 and separating solvent B. Evaporator 21 is provided with a high-temperature heat exchanger 22 that heats electrolyte solution X consisting of solvent A and solvent B, and in evaporator 21, solvent B is evaporated from electrolyte solution X by heating in high-temperature heat exchanger 22, which exchanges heat with a high-temperature heat source, to separate solvent B (means using thermal energy). Electrolyte solution X from which solvent B has been separated in evaporator 21 is introduced into second tank 2 as electrolyte solution Y by pump 23 (supply / discharge means: second electrolyte regeneration means).

[0065] In the figure, reference numeral 24 denotes a heat exchanger (heat exchanger with a high-temperature heat source) that heats the electrolyte X on the inlet side of the evaporator 21, 25 denotes a temperature detection means that detects the temperature of the electrolyte X on the inlet side of the evaporator 21, 26 denotes a pressure detection means that detects the pressure of the electrolyte Y that is poured into the second tank 2, and 27 denotes a temperature detection means that detects the temperature of the electrolyte Y that is poured into the second tank 2.

[0066] A condenser 31 is provided that condenses the solvent B separated in the evaporator 21, and in the condenser 31, the solvent B separated in the evaporator 21 is condensed by heat exchange in a heat exchanger 32, which is a low-temperature heat source. Meanwhile, a mixer 33 is provided to which the post-reaction electrolytic solution Y is sent after being discharged from the second tank 2, and the solvent B condensed in the condenser 31 is sent to the mixer 33. In the mixer 33, the post-reaction electrolytic solution Y and the solvent B condensed in the condenser 31 are mixed (to produce electrolytic solution X), and the resulting mixture is introduced into the first tank 1 (supply / discharge means: first electrolytic solution regeneration means).

[0067] A flow path 34 that sends the solvent B separated in the evaporator 21 to the condenser 31 is provided with a temperature detection means 35, a pressure detection means 36, and a relief valve 37. The condenser 31 is also provided with a temperature detection means 38 that detects the temperature of the condensed solvent B. The post-reaction electrolyte Y extracted from the second tank 2 is heat exchanged in a heat exchanger 39 that is a low-temperature heat source, and sent to the mixer 33. The solvent B condensed in the condenser 31 is sent to the mixer 33 by a pump 41, mixed with the post-reaction electrolyte Y from the second tank 2, and sent to the first tank 1 by a pump 42 (supply / discharge means).

[0068] In the figure, reference numeral 45 denotes a pressure detection means for detecting the pressure of solvent B sent to mixer 33, and reference numeral 46 denotes a temperature detection means for detecting the temperature of solvent B. Also in the figure, reference numeral 47 denotes a temperature detection means for detecting the temperature of electrolytic solution Y after the reaction sent from second tank 2 to mixer 33. Also in the figure, reference numeral 48 denotes a pressure detection means for detecting the pressure of electrolytic solution X (solvent A + solvent B) sent from mixer 33 to first tank 1, and reference numeral 49 denotes a temperature detection means for detecting the temperature of electrolytic solution X (solvent A + solvent B).

[0069] In the power generation system having the above configuration, hexacyanoferrate (II) ions [Fe(CN)6] are added to the first tank 1. 4- is oxidized to form hexacyanoferrate(III) ion [Fe(CN)6] 3- In addition, in the second tank 2, hexacyanoferrate (III) ions [Fe(CN)6] 3- is reduced to form hexacyanoferrate(II) ion [Fe(CN)6] 4- Negative electrons (e - ) moves from the first tank 1 to the second tank 2, causing a current to flow in the power circuit 5.

[0070] In other words, the reactions at the positive and negative electrodes involve the same redox pair (hexacyanoferrate (II) ion [Fe(CN)6] 4- , hexacyanoferrate(III) ion [Fe(CN)6] 3- ) is the reverse reaction of the above, and the difference in the active material-solvent interaction caused by the difference in the solvent composition between the electrodes creates a potential difference, and an oxidation or reduction reaction occurs at each electrode.

[0071] Electrolyte solution X after the reaction, which is composed of solvent A and solvent B, is extracted from first tank 1, and solvent B is separated in evaporator 21. Electrolyte solution X from which solvent B has been separated in evaporator 21 is introduced as electrolyte solution Y into second tank 2 by pump 23 (supply / discharge means: second electrolyte solution regeneration means).

[0072] Electrolyte solution Y after the reaction is extracted from second tank 2 and sent to mixer 33. Solvent B evaporated in evaporator 21 and condensed in condenser 31 is sent to mixer 33, where electrolytic solution Y and solvent B are mixed to form electrolytic solution X. Electrolyte solution X from mixer 33 is sent to first tank 1 (supply / discharge means: first electrolyte regeneration means).

[0073] By utilizing thermal energy, solvent B is vaporized and separated from electrolyte solution X after the electrode reaction, and sent to second tank 2 as electrolyte solution Y. By mixing with electrolyte solution Y after the electrode reaction, it is sent again to first tank 1 as electrolyte solution X.

[0074] Therefore, no chemical substances are consumed overall, and by using a high-temperature heat exchanger 22 (high-temperature heat source) that can vaporize solvent B and a heat exchanger 32 (low-temperature heat source) that can condense it, it can be operated in the same way as a heat engine, making it possible to generate electricity continuously. By using a substance with a relatively low boiling point as solvent B, it becomes possible to use a heat source of about 100°C as the high-temperature heat source. An example of a substance with a relatively low boiling point is acetone.

[0075] This means that the effective use of heat sources below 100°C, such as industrial waste heat, geothermal heat, and hot spring heat, which have not been fully utilized, will be dramatically improved. Furthermore, because the equipment containing the first tank 1, second tank 2, negative electrode 3, and positive electrode 4 that generate electricity is separate from the equipment that recovers heat and regenerates and circulates the electrolyte, the design has a high degree of freedom and application to large-scale power generation systems is easily possible. Furthermore, by storing the electrolyte after separating and remixing solvent B, energy can be stored, and the amount of power generation can be controlled according to demand.

[0076] The above-described power generation system can maintain power generation without emitting carbon dioxide, making it possible to achieve both a stable supply of power and a reduction in carbon dioxide emissions.

[0077] In the above embodiment, the electrolyte is regenerated by the first electrolyte regeneration means and the second electrolyte regeneration means. An example of the change in voltage over time when the electrolyte is regenerated will be described with reference to FIG. 9. As shown in FIG. 9, as the reaction progresses, the voltage (V) decreases and reaches a voltage threshold V1 at time t1. When the voltage reaches threshold V1, the reacted electrolyte X is sent to the evaporator 21, and the reacted electrolyte Y is sent to the mixer 33.

[0078] Solvent B is separated in evaporator 21 and sent to mixer 33, electrolyte X (solvent A + solvent B) is regenerated, and electrolyte X containing the pre-reacted active material is supplied to first tank 1 (time t1 to time t2). Solvent A after solvent B has been separated in evaporator 21 is supplied to second tank 2 as electrolyte Y containing the pre-reacted active material (time t1 to time t2).

[0079] As a result, as shown in FIG. 9, the voltage recovers sufficiently at time t2, and the desired voltage (electromotive force equal to or greater than the threshold value V1) is maintained until time t3.

[0080] Although Figure 9 shows an example of the change over time when regeneration is performed after discharge due to the reaction, it is also possible to perform regeneration while performing discharge due to the reaction (in parallel with discharge).

[0081] A third embodiment of the present invention will be described with reference to Fig. 10. Fig. 10 shows the overall configuration of a power generation system using potential difference according to the third embodiment of the present invention. Note that the same components as those in the power generation system shown in Fig. 8 are denoted by the same reference numerals.

[0082] The power generation system shown in Figure 10 is configured such that a pressure adjustment section 52 (internal pressure adjustment means) that adjusts the pressure inside the flow path 34 (closed flow path of the supply and discharge means) is provided in addition to the power generation system of the second embodiment shown in Figure 8.

[0083] As shown in the figure, a three-way valve 51 is provided in the flow path 34 upstream of the relief valve 37, and a pressure adjusting unit 52 (internal pressure adjusting means) that adjusts the pressure inside the flow path 34 is connected to the three-way valve 51. The pressure adjusting unit 52 is, for example, a cylinder, a pump, or the like, and is a device that applies pressure or pressure reduction to the inside of the flow path 34 (solvent B).

[0084] The pressure adjustment unit 52 increases or decreases the pressure inside the flow path 34 (solvent B). This allows the boiling point of solvent B to be adjusted, and a heat source with a temperature corresponding to the adjusted boiling point of solvent B can be used as the heat source for the high-temperature heat exchanger 22. Furthermore, the boiling point of solvent B can be controlled in accordance with the temperature of the heat source for the high-temperature heat exchanger 22. This makes it possible to effectively use a wide range of heat sources.

[0085] A fourth embodiment of the present invention will be described with reference to Fig. 11. Fig. 11 shows the overall configuration of a power generation system according to the fourth embodiment of the present invention. The same components as those in the power generation system shown in Fig. 1 are denoted by the same reference numerals. In the power generation system shown in Fig. 11, the solvent of the electrolyte contained in the first tank 1 and the second tank 2 is the same as that in the power generation system shown in Fig. 1, and the active material is also the same as that in the power generation system shown in Fig. 1.

[0086] In the fourth embodiment, the separation of solvent B in the first electrolyte regeneration means and the second electrolyte regeneration means and the remixing of solvent B are performed by means using mechanical energy. The fourth embodiment has a separation supply means that pressurizes the electrolyte X discharged from the first tank 1 and causes it to pass through a separation means (permeable membrane) to separate solvent B, and supplies the electrolyte Y from which solvent B has been separated (under reduced pressure) to the second tank 2, and a mixing supply means that remixes the low-pressure solvent B that has passed through the separation means with the electrolyte Y discharged from the second tank 2 and supplies the remixed solution to the first tank 1.

[0087] As shown in FIG. 11, the device is provided with a first tank 1 containing an electrolytic solution X, which is a mixture of solvents A and B. It is also provided with a second tank 2 containing an electrolytic solution Y made from solvent A. The first tank 1 is provided with a negative electrode (negative electrode) 3, and the second tank 2 is provided with a positive electrode (positive electrode) 4. The negative electrode 3 and the positive electrode 4 are connected to a power circuit (external circuit) 5, and a current flows in the power circuit 5 due to a potential difference caused by the difference in composition between the first solvent (solvent A + solvent B) in the first tank 1 and the second solvent (solvent A) in the second tank 2.

[0088] After the active material of the electrolyte solution X consisting of solvent A and solvent B has completed the electrode reaction, a separation means is provided to extract the electrolyte solution X from the first tank 1 and separate the solvent B. The separation means is a means that uses mechanical energy, and includes a compression means 61 that pressurizes the electrolyte solution X extracted from the first tank 1. The compression means 61 is driven by renewable energy such as wind power, water power, wave power, or tidal power.

[0089] The compressed electrolytic solution X is sent to a high-pressure chamber 62a of a separation tank 62. The separation tank 62 is provided with a low-pressure chamber 62b via a permeable membrane 63 that allows only solvent B to pass through. By sending the compressed electrolytic solution X to the high-pressure chamber 62a, only solvent B passes through the permeable membrane 63, and the solvent B is sent to the low-pressure chamber 62b and separated (separation supply means).

[0090] The electrolyte in the high-pressure chamber 62a (electrolyte from which solvent B has been separated: electrolyte Y) is depressurized by the pressure reducing means 70 and is fed into the second tank 2 as electrolyte Y by the pump 23 (supply / discharge means: second electrolyte regeneration means).

[0091] In the figure, reference numeral 64 denotes a temperature detection means for detecting the temperature of the electrolyte X on the inflow side of the compression means 61, 65 denotes a pressure detection means for detecting the pressure of the electrolyte X on the inflow side of the compression means 61, 66 denotes a temperature detection means for detecting the temperature of the electrolyte X on the outflow side of the compression means 61, 67 denotes a pressure detection means for detecting the pressure of the electrolyte X on the outflow side of the compression means 61, and 68 denotes a relief valve.

[0092] The low-pressure chamber 62b is supplied with the electrolyte solution Y discharged from the second tank 2 via the pump 69, and is remixed with the solvent B that has permeated the permeable membrane 63 (mixing and supplying means). The solvent B is remixed to form the electrolyte solution X, which is sent to the first tank 1 by the pump 42 (supply and discharge means: first electrolyte regeneration means).

[0093] In the figure, reference numeral 71 denotes a temperature detecting means for detecting the temperature of the electrolyte Y on the outflow side of the pump 69 , and reference numeral 72 denotes a pressure detecting means for detecting the pressure of the electrolyte Y on the outflow side of the pump 69 .

[0094] In addition, in the figure, reference numeral 75 denotes a storage tank for storing the electrolytic solution X after the reaction, 76 denotes a storage tank for storing the electrolytic solution Y after the reaction, 77 denotes a storage tank for storing the electrolytic solution X after the regeneration, and 78 denotes a storage tank for storing the electrolytic solution Y after the regeneration.

[0095] By storing the reacted electrolyte in storage tanks 75 and 76, it is possible to adjust the supply of the reacted electrolyte to separation tank 62 in response to fluctuations in the output of compression means 61 driven by renewable energy. In addition, by storing the regenerated electrolyte in storage tanks 77 and 78, it is possible to adjust the output in response to fluctuations in power demand.

[0096] A post-reaction electrolyte solution X consisting of solvent A and solvent B is extracted from first tank 1, pressurized by compression means 61, and sent to separation tank 62, where solvent B is separated. Electrolyte solution X from which solvent B has been separated is depressurized by depressurization means 70 and introduced into second tank 2. A post-reaction electrolyte solution Y is extracted from second tank 2, sent to low-pressure chamber 62b of separation tank 62, and mixed with solvent B to form electrolyte solution X, which is then sent to first tank 1. Mechanical energy is used to separate solvent B from electrolyte solution X after the electrode reaction, and the electrolyte solution from which solvent B has been separated is sent to second tank 2 as electrolyte solution Y. Electrolyte solution Y after the electrode reaction is mixed with the separated solvent B, and the resulting electrolyte is sent again to first tank 1 as electrolyte solution X.

[0097] This means that there is no overall consumption of chemical substances, and it is possible to generate electricity continuously using mechanical renewable energy sources such as water, wind, wave, and tidal power, just as with thermal energy.

[0098] The above-described power generation system can maintain power generation without emitting carbon dioxide, making it possible to achieve both a stable supply of power and a reduction in carbon dioxide emissions. [Industrial Applicability]

[0099] The present invention is a power generation system that can stably supply electricity without emitting carbon dioxide. Mu's It can be used in the industrial field. [Explanation of symbols]

[0100] 1 Tank 1 2 2nd tank 3 negative electrode 4 positive electrode 5 Power circuit 11 First Tank 12, 16, 23, 41, 42, 69 Pumps 13 First Recovery Tank 15 Second Tank 17 Second Recovery Tank 19, 25, 27, 35, 38, 46, 47, 49, 64, 66, 71 Temperature detection means 21 Evaporator 22, 24 High temperature heat exchanger 32, 39 Heat exchanger 26, 36, 45, 48, 65, 67, 72 Pressure detection means 31 Condenser 33 Mixer 34 Flow path 37, 68 Relief valve 51 Three-way valve 52 Pressure adjustment section 61 Compression Method 62 Separation tank 63 Permeable membrane 70 Pressure reduction means 75, 76, 77, 78 Storage tanks

Claims

1. a first tank containing an electrolytic solution of a first solvent, having one electrode, and in which an active material undergoes an electrode reaction; a second tank containing an electrolytic solution of a second solvent different from the electrolytic solution contained in the first tank, the second tank having the other electrode, and in which the active material undergoes an electrode reaction; The electrode reaction caused by the active material in the first tank and the electrode reaction caused by the active material in the second tank are reverse reactions caused by the same redox pair. A power generation system using a potential difference caused by different solvents.

2. In the power generation system using the potential difference caused by the heterogeneous solvents according to claim 1, The first solvent and the second solvent contain at least one of the same substances. A power generation system using a potential difference caused by different solvents.

3. A power generation system using a potential difference caused by the different solvents according to claim 1 or claim 2, The first solvent and the second solvent include at least one of water, ethanol, methanol, acetonitrile, dimethyl sulfoxide, acetone, pyridine, dimethylacetamide, dimethylformamide, hexamethylphosphoramide, propylene carbonate, tetrahydrofuran, and N-methyl-2-pyrrolidone. A power generation system using a potential difference caused by different solvents.

4. A power generation system using a potential difference caused by the different solvents according to claim 1 or claim 2, At least one of the first solvent and the second solvent contains a salt having a melting point of 200° C. or less at 1 atm. A power generation system using a potential difference caused by different solvents.

5. A power generation system using a potential difference caused by a heterogeneous solvent according to any one of claims 1 to 4, A supply / discharge means is provided for supplying an electrolytic solution from the outside into the first tank and the second tank, and discharging the electrolytic solution after the active material has undergone an electrode reaction to the outside of the first tank and the second tank. A power generation system using a potential difference caused by different solvents.

6. In the power generation system using the potential difference caused by the heterogeneous solvents according to claim 5, the first solvent and the second solvent are a mixture of solvent A and solvent B; the first solvent comprises a greater amount of solvent B than the second solvent; The supply and discharge means is An electrolytic solution of the first solvent consisting of the solvent A and the solvent B is supplied from the outside to the first tank, the electrolytic solution after the active material has undergone an electrode reaction is discharged from the first tank, a part or all of the solvent B is separated and recovered from the discharged electrolytic solution, the electrolytic solution after the part or all of the solvent B has been separated is supplied to the second tank, the electrolytic solution after the active material has undergone an electrode reaction opposite to the electrode reaction in the first tank is discharged to the outside, the separated and recovered solvent B is remixed with the discharged electrolytic solution, and the electrolytic solution after the solvent B has been remixed is supplied to the first tank. A power generation system using a potential difference caused by different solvents.

7. A power generation system using a potential difference caused by a different solvent according to claim 6, a second electrolytic solution regeneration means as a means for separating and recovering the solvent B from the electrolytic solution discharged from the first tank and supplying the electrolytic solution from which the solvent B has been separated to the second tank; The electrolytic solution discharged from the second tank is remixed with the solvent B separated and recovered from the electrolytic solution discharged from the first tank, and the remixed electrolytic solution with the solvent B is supplied to the first tank. A power generation system using a potential difference caused by different solvents.

8. A power generation system using a potential difference caused by a different solvent according to claim 7, The separation of the solvent B and the remixing of the solvent B in the first electrolyte regeneration means and the second electrolyte regeneration means are performed by means using thermal energy. A power generation system using a potential difference caused by different solvents.

9. A power generation system using a potential difference caused by a different solvent according to claim 8, The means using thermal energy is an evaporation means for heating the electrolytic solution discharged from the first tank to evaporate the solvent B, and supplying the electrolytic solution from which the solvent B has been separated to the second tank; a condensing means for condensing the solvent B evaporated by the evaporating means, remixing the solvent B with the electrolytic solution discharged from the second tank, and supplying the remixed solution to the first tank; A power generation system using a potential difference caused by different solvents.

10. A power generation system using a potential difference caused by different solvents according to claim 8 or claim 9, The supply and discharge means is provided with an internal pressure adjusting means for adjusting the pressure inside the electrolyte flow path. A power generation system using a potential difference caused by different solvents.

11. A power generation system using a potential difference caused by a different solvent according to claim 7, The separation of the solvent B in the first electrolyte regeneration means and the remixing of the solvent B in the second electrolyte regeneration means are performed by means using mechanical energy. A power generation system using a potential difference caused by different solvents.

12. A power generation system using a potential difference caused by the different solvents according to claim 11, The means using mechanical energy is a separation and supply means for pressurizing the electrolytic solution discharged from the first tank and passing it through a separation means to separate the solvent B, and supplying the electrolytic solution from which the solvent B has been separated to the second tank; a mixing and supplying means for remixing the solvent B that has permeated the separating means with the electrolytic solution discharged from the second tank and supplying the remixed solution to the first tank; A power generation system using a potential difference caused by different solvents.

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