ELECTRICITY PRODUCTION FACILITY COMPRISING A FUEL CELL AND A CHEMICAL REACTOR SUITABLE FOR PRODUCING FUEL FOR SAID FUEL CELL USING HEAT RELEASED BY A BATTERY ASSOCIATED PROCESS

Abstract

The present invention is a method for producing electricity comprising a fuel cell which makes it possible to valorize the heat given off by the cell to generate fuel for said fuel cell by a process of thermal dissociation, applied to the product of the same chemical composition than that produced by the cell, at least part of the heat given off by the cell being supplied to at least one of the endothermic reactions of said dissociation process.

Claims

1. A method for producing electricity implementing a non-galvanic fuel cell (1), said method comprising: recovering heat given off by the cell (1) to generate fuel for said fuel cell by a thermal dissociation process, and applying a product of the same chemical composition as one of the products of said fuel cell, wherein at least part of the heat given off by said fuel cell being supplied to at least one endothermic reactions of said dissociation process.

2. The method according to claim 1, wherein oxidizers and fuels of the fuel cell not reacting directly with each other outside of said cell.

3. The method according to claim 1, further comprising: the fuel enters an installation and mixes with the fuel, the said fuel cell (1) producing electricity which is one of the products of the installation, as well as at least one product which is partly extracted from the installation and partly recycled to the reactors of the chemical cycle, the heat released by the cell(1) being transferred to the chemical cycle which produces fuel.

4. The method according to claim 1, wherein each of the thermal dissociation products being used in part by the cell.

5. The method according to claim 1, wherein a part of the product or products of the cell being used for the chemical dissociation.

6. The method according claim 1 wherein the fuel cell (1) generating electricity uses dihydrogen as reducing fuel and operates at a selected operating temperature, said cell (1) being connected to a source of dihydrogen, and the process of thermal dissociation of water being the sulfur iodine cycle in which the following chemical reactions are carried out: a. 2 H2SO4.fwdarw.2 SO2+2 H2O+O2 b. 2 HI.fwdarw.I2+H2 c. I2+SO2+2 H2O.fwdarw.2 HI+H2SO4

7. The method according to claim 1, wherein the fuel cell (1) generating electricity uses dihydrogen as reducing fuel and operates at a selected operating temperature, said cell (1) being connected to a source of dihydrogen, and the thermal water dissociation process being a cycle using bromine and during which the following reactions are used: a. 2 H2SO4.fwdarw.2 SO2+2 H2O+O2 b. 2HBr.fwdarw.Br2+H2 c. Br2+SO2+2 H2O.fwdarw.2 HBr+H2SO4

8. The method according to claim 1, wherein the fuel cell (1) generating electricity uses dihydrogen as reducing fuel and operates at a selected operating temperature, said cell (1) being connected to a source of dihydrogen and the thermal water dissociation process is a sulfur cycle using chlorine and during which the following reactions are used: a. 2 H2SO4.fwdarw.2 SO2 +2 H2O+O2 b. 2HCl.fwdarw.Cl2+H2 c. Cl2+SO2+2 H2O.fwdarw.2 HCl+H2SO4

9. The method according to claim 1, wherein the fuel cell (1) generating electricity uses dihydrogen as reducing fuel and operates at a selected operating temperature, said cell (1) being connected to a source of dihydrogen and the thermal water dissociation process uses an alkali metal hydride in which water mixed with the alkali metal reacts to form an alkali metal hydride and dioxygen (H2O+2 Me−>2MeH+½ O2) while the alkali metal hydride is transformed in another reactor into metal and dihydrogen (2MeH−>2Me+H2).

10. The method according to claim 1, wherein the fuel cell (1) generating electricity uses dihydrogen as reducing fuel and operates at a selected operating temperature, said cell (1) being connected to a source of dihydrogen and the thermal water dissociation process uses Iron III chloride and Iron II chloride (6FeCl2+8H2O−>2Fe3O4+12HCl+2H2; 2Fe3O4+12HCl+3Cl2−>6FeCl3+6H2O+O2 and 6FeCl 3−>6FeCl2+3Cl2).

11. The method according to claim 1, wherein the fuel cell (1) generating electricity uses dihydrogen as reducing fuel and operates at a selected operating temperature, said cell (1) being connected to a source of dihydrogen and the thermal water dissociation process uses vanadium chloride and vanadium tetrachloride (Cl2+H2−>2HCl+½ O2; 2HCl+VCl2−>2VCl3+H2; 2VCl3−>VCl2+VCl4; 2VCl4−>2VCl3+Cl2).

12. The method according to claim 1, wherein the fuel cell (1) generating electricity uses dihydrogen as reducing fuel and operates at a selected operating temperature, said cell (1) being connected to a source of dihydrogen and the thermal water dissociation process uses hydrocarbons.

13. The method according to claim 12, wherein the hydrocarbon being methane reacting in a first reactor with water to form dihydrogen and carbon monoxide (CH4+H2O−>CO+3H2), carbon monoxide and dihydrogen reacting in a second reactor to form methanol (CO+2H2−>CH3OH), methanol reacting in a third reactor with arsenate to form arsenious anhydride and dioxygen (CH3OH+As2O4−>½ As2O3+½ O2), a fourth and a fifth reactor providing the formation of arsenate and dioxygen from arsenious anhydride (1/2 As2O5−>½ As2O3+½ O2 and ½ As2O5+½ As2O3−>As2O4).

14. The method according to claim 1, wherein the fuel cell (1) generating electricity uses methanol as fuel.

15. A system for the production of electricity, comprising: at least one fuel cell (1) generating electricity and using dihydrogen as reducing fuel and operating at a selected operating temperature, said cell (1) being connected to a main source of dihydrogen; a chemical reactor/chemical production unit (3) thermally connected to said cell and providing the chemical production of dihydrogen via an endothermic chemical reaction which takes place at a temperature lower than or equal to said operating temperature of said cell (1), and means (141) for introducing into said fuel cell (1) the dihydrogen produced in said chemical reactor (3), characterized in that said chemical reactor/said chemical production unit (3) comprises at least one main compartment/ main reactor (310) allowing the chemical production of dihydrogen, a first secondary compartment/first secondary reactor (311) allowing the chemical production of dioxygen, and in that said first compartment/secondary reactor (311) and/or said reactor/compartment main (310) are thermally connected to said cell (1), in that it further comprises means (142) for introducing the diatomic iodine produced in said main compartment/reactor (310) to said second compartment/ secondary reactor (312), means for introducing the sulfuric acid produced in said second compartment/secondary reactor (312) into said first compartment/secondary reactor (311) and means for introduction of the dioxygen produced in said first compartment/secondary reactor (311) to said cell (1) so that the latter serves there as fuel.

16. The system according to claim 15, wherein said chemical reactor/said chemical production unit (3) comprises at least one main compartment/main reactor (310) allowing the chemical production of dihydrogen and di-iodine from iodide of hydrogen, a first secondary compartment/first secondary reactor (311) allowing the chemical production of dioxygen from the reaction between two molecules of sulfuric acid and at least a second secondary compartment/second secondary reactor which allows the reaction between the di-iodine, sulfur oxide and water, which produces hydrogen iodide and sulfuric acid.

17. canceled

18. canceled

Description

FIGURES

[0047] The present invention, its characteristics and the various advantages it provides will appear better on reading the following description, presented by way of illustrative and non-limiting example, and which refers to the appended FIGS. 1 to 4:

[0048] FIG. 1 represents a schematic view of a particular embodiment of the present invention; and

[0049] FIG. 2 represents a diagram of the various flows of matter and energy necessary for the invention, entering, leaving and internal to the installation.

[0050] FIG. 3 represents a diagram of the various flows of material and energy necessary for the invention, entering, leaving and internal to the installation, the fuel being methanol.

[0051] FIG. 4 represents a diagram of the various flows of material and energy necessary for the invention, using a dihydrogen-water separator making it possible to maintain the proportion of dihydrogen in the gaseous mixture supplied to the anode of the cell.

EXAMPLES

[0052] With reference to FIG. 1, a first embodiment of the invention will now be described. The installation comprises a cell 1, which is a solid metal oxide fuel cell. Despite its operation at high temperature (from 850° C. to 1000° C.), cell 1 gives off heat. Cell 1 is thermally connected to a chemical reactor 3, which has three compartments. A thermal gradient is present in the chemical reactor 3 in order to ensure the appropriate reaction temperatures. The two upper compartments of the reactor are thermally connected to each other. The chemical reactor 3 comprises a main compartment 310 which is central in FIG. 1. A first secondary compartment 311 is located above the main compartment 310. This first secondary compartment 311 is arranged so as to first recover the heat produced by the battery 1 so that the temperature within it is higher than in the main compartment 310. A second secondary compartment 312 is arranged under the main compartment 310; the di-iodine from the separator 14 is advantageously brought into the tank 312 at a temperature of 120° C. in liquid form; a mixture of water and sulfur dioxide is supplied from the separator 65 and from a supply of water introduced via line 164, preferably also at a temperature of 120° C., and preferably under a pressure allowing that the two components of this gaseous mixture are liquid, the partial pressure of the sulfur dioxide being for example 50 bars.

[0053] The temperature of the second secondary compartment 312 is lower than that of the main compartment 310. In FIG. 1, the two upper compartments are thermally connected so that the heat is transmitted from the first secondary compartment to the main compartment. The arrangement of the compartments is not limited to that shown in FIG. 1. In particular, the compartments may not have a common wall through which the heat is transmitted. For example, a heat transfer liquid whose speed is regulated circulates between the 3 compartments to heat the said compartments and maintain them at the temperature necessary for the chemical reactions they house, if these are the sites of endothermic reactions.

[0054] The residual heat resulting from the operation of the installation is evacuated at the level of the second secondary compartment 312, for example by means of a cooling circuit (not shown) in which a heat transfer liquid circulates. A portion of this circuit crosses said compartment or is in contact with the wall of the latter. This heat can be used, for example, to produce electricity by means of a turbine. For this purpose, the installation may also include an electricity production turbine.

[0055] Still with reference to FIG. 1, the installation comprises a gas separator 14 whose inlet is located at the outlet of the main compartment 310. The outlet of this separator 14 is connected by a pipe 141 to the battery and by a pipe 142 to the second secondary compartment 312 The separator 14 can operate for example by concomitant expansion and cooling of the gas coming from the compartment 310, the di-iodine becoming liquid, between 184° C. and its critical temperature being 545.8° C. The liquid di-iodine is then optionally recompressed to reach the operating pressure of reactor 312.

[0056] The installation also comprises a separator 16 arranged at the entrance to the main compartment 310. The entrance to the separator 16 is connected via a pipe 161 to the second secondary compartment 312. The exit from the separator 16 is connected on the one hand to the main compartment 310 via a pipe 162 and on the other hand to the first compartment 311 via another pipe 163. At a temperature of 120° C., hydrogen iodide HI is gaseous and the other components, including sulfuric acid, are liquid under 50 bars. The reaction product mixture from reactor 312 is therefore preferably withdrawn from said reactor 312 after the reaction is complete. The pressure of the hydrogen iodide is advantageously lowered to the operating pressure of the reactor 310, to for example 10 bars.

[0057] A third separator 65 has its inlet connected to the first secondary compartment 311 (pipe not referenced and indicated by an arrow in FIG. 1) and its outlet connected by a first pipe (not shown) to the battery 1 and by a second pipe (not shown), to the second secondary compartment 312. The separator 65 operates for example by one or a series of compressions followed by cooling of the gas resulting from the decomposition of the sulfuric acid.

[0058] The operation of the installation will now be described with reference to FIG. 1. In the main compartment 310, the following chemical reaction takes place:

[0059] 2HI.fwdarw.I.sub.2+H.sub.2. This reaction takes place at a temperature of about 650° C. in the gas phase.

[0060] In the first secondary compartment 311, the following chemical reaction takes place:

[0061] 2H.sub.2SO.sub.4.fwdarw.2SO.sub.2+2H.sub.2O+O.sub.2. This reaction takes place at a temperature of about 830° C. in the gas phase.

[0062] In the second secondary compartment, the following chemical reaction takes place:

[0063] I.sub.2+SO.sub.2+2H.sub.2O.fwdarw.2HI+H.sub.2SO.sub.4. This reaction is endothermic and takes place at a temperature of the order of 120° C., the liquid di-iodine, mixed with liquid water and sulfur dioxide reacting advantageously with each other or, alternatively for example, the di-iodine in liquid form being vaporized in an atmosphere composed of water vapor and sulfur dioxide.

[0064] Cell 1 produces electricity supplying a network not shown in FIG. 1, by consuming dihydrogen. The heat given off by cell 1 is used to heat the first secondary compartment 311 of chemical reactor 3. In the particular embodiment represented here, only this compartment is thermally connected to cell 1. In this first secondary compartment, the acid sulfur reacts on itself to produce water, oxygen and sulfur dioxide. The reaction products are separated in the separator 65; the sulfur dioxide and the water are brought into the second secondary compartment 312; the oxygen is brought to cell 1 to serve, in addition to the oxygen brought elsewhere, for example from the outside air, to the oxidation-reduction reaction which takes place in the latter.

[0065] Due to the heat supplied, either directly from cell 1, or after transit in the first secondary compartment 311, the reaction which takes place in the main compartment 310 produces gaseous di-iodine and gaseous dihydrogen. These produced gases are separated in the separator 14; the dihydrogen is routed (via line 141) to cell 1 to react there. The gaseous iodine leaving the separator 14 is routed via line 142 to the second secondary compartment 312.

[0066] In the second secondary compartment 312, iodine reacts with sulfur dioxide and water from the first secondary compartment to produce hydrogen iodide (HI) and sulfuric acid. These products are separated in the separator 16; the hydrogen iodide is separated and brought to the main compartment 310 in order to feed the reaction in the latter; the sulfuric acid is brought into the first secondary compartment by line 163 connected to separator 16.

[0067] FIG. 2

[0068] The fuel 201 enters the installation 200 and mixes with the fuel 203 from the chemical cycle reactors 212 to be introduced at 205 into the fuel cell 207. Similarly, the oxidizer is introduced into the installation (202) to be mixed with the oxidizer 204 from the chemical cycle reactors 212, to be introduced at 206 into the fuel cell 207. The fuel cell produces electricity 209 which is one of the products of the installation, as well as a product, for example water which is partly extracted from the installation at 211 and partly recycled at 210 to the reactors of the chemical cycle. The heat 208 given off by the battery 207 is transferred to the chemical cycle 212. The chemical cycle produces fuel 203; oxidizer 204 and possibly residual heat 213 extracted from the installation.

[0069] FIG. 3

[0070] The methanol 501 enters the installation 500 and mixes with the methanol 503 from the chemical cycle reactors 512 to be introduced at 505 into the direct methanol fuel cell 507. Similarly, the oxygen is introduced into the installation 502 to be mixed with the dioxygen 504 from the chemical cycle reactors 512, to be introduced at 506 into the fuel cell 507. The fuel cell produces electricity 509 which is one of the products of the installation, as well as water and carbon dioxide 511 which are partly extracted from the installation at 511 and partly recycled at 510 to the reactors of the chemical cycle. The heat 508 released by the battery 507 is transferred to the chemical cycle 512. The chemical cycle produces methanol 503; oxygen 504 and possibly residual heat 513 extracted from the installation.

[0071] FIG. 4

[0072] The gaseous mixture brought to the anode of the battery 1 is put into circulation, that is to say brought and withdrawn by the conduit(s) 153 to be in thermal and gaseous communication with the device 150 which is in thermal contact by the connection 152 with the reactor 310 at a temperature of approximately 650° C. to which said gas mixture is therefore cooled. The gaseous mixture is enriched in dihydrogen in the device 150 using one or more metal membranes which makes it possible to extract the dihydrogen therefrom and/or the water which is rejected by the pipe 154. This water is advantageously used in part (not shown), to supply the dihydrogen production cycle, then being introduced into line 164. Similarly, the heat from this water is advantageously supplied to reactor 312 (not shown), or to heat the dihydrogen and/or dioxygen introduced into the installation.