ENERGY PRODUCTION DEVICE COMPRISING A DIHYDROGEN PRODUCTION UNIT; METHOD USIING THIS DEVICE

Abstract

An energy production device may include: a supply device for hydrocarbon gas; energy converter configured to convert the energy supplied by the H.sub.2 into electrical, thermal, and/or mechanical energy; H.sub.2 producer fluidically between the supply device and the energy converter; the H.sub.2 producer including a plasmalysis reactor configured to generate plasmalysis of the hydrocarbon gas so as to produce at least one dihydrogen directed towards the energy converter; a controller configured to generate a control instruction for the H.sub.2 producer with information on H.sub.2 present in a H.sub.2 distribution area arranged fluidically between the plasmalysis reactor and the energy converter, the H.sub.2 distribution area including a storage assembly at the plasmalysis reactor outlet and hydraulically connected to the plasmalysis reactor and energy converter, the storage assembly including a compression device, storage tank, and expander, the compression device being positioned to transfer H.sub.2 exiting the plasmalysis reactor into the storage tank.

Claims

1. An energy production device, comprising: hydrocarbon gas supply device configured for supplying hydrocarbon; an energy conversion unit; a dihydrogen production unit fluidically arranged between the hydrocarbon gas supply device and the energy conversion unit, the energy conversion unit being configured to convert energy supplied by H.sub.2 into electrical, thermal, and/or mechanical energy; a microwave plasma plasmalysis reactor configured to generate a plasmalysis of the hydrocarbon gas so as to produce at least dihydrogen directed to the energy conversion unit, the dihydrogen production unit further comprising a separation device, configured to separate the dihydrogen and the solid carbon; a control module configured to generate a control instruction for the dihydrogen production unit as a function of information relating to H.sub.2 present in a dihydrogen distribution area fluidically arranged between the plasmalysis reactor and the energy conversion unit, wherein the dihydrogen distribution area comprises a storage assembly arranged at an outlet of the plasmalysis reactor and hydraulically connected to the plasmalysis reactor and the energy conversion unit, the storage assembly comprising a compression device, a storage tank, and an expander, the compression device being positioned to transfer H.sub.2, exiting the plasmalysis reactor, into the storage tank, and wherein the H.sub.2 exiting the separation device equipping the dihydrogen production unit then circulates in the dihydrogen distribution area fluidically arranged between the plasmalysis reactor and the energy conversion unit.

2. The energy production device of claim 1, wherein the control instruction of the dihydrogen production unit comprises a control instruction for the hydrocarbon gas intake via the supply device and/or for the plasmalysis reactor.

3. The energy production device of claim 1, wherein the plasmalysis reactor comprises microwave radiation generator, a microwave transmission guide configured to guide microwave radiation from the microwave radiation generator to a microwave radiation cavity of the plasmalysis reactor.

4. The energy production device of claim 3, wherein the control instruction for the plasmalysis reactor comprises a control instruction for the microwave radiation generator.

5. The energy production device of claim 3, wherein the plasmalysis reactor comprises a plasma ignition device comprising a retractable metal tip configured to be inserted or retracted in the microwave radiation cavity using an actuator.

6. The energy production device of claim 5, wherein the control instruction for the plasmalysis reactor comprises a control instruction for the ignition device.

7. The energy production device of claim 3, wherein the microwave radiation generator is a solid-state generator or a magnetron.

8. The energy production device of claim 1, wherein the control instruction of the dihydrogen production unit comprises an instruction for controlling the compression device.

9. The energy production device of claim 1, wherein the information relating to the H.sub.2 present in a dihydrogen distribution area from which the control module is configured to control the operation of the dihydrogen production unit is information relating to the H.sub.2 present in the storage assembly.

10. The energy production device of claim 9, wherein the information relating to the H.sub.2 present in the dihydrogen distribution area is obtained via a pressure gauge, and wherein the control module is configured to generate and transmit a control instruction to the dihydrogen production unit when a pressure measured by the gauge is below a threshold value.

11. The energy production device of claim 1, wherein a filtration system is arranged upstream of the plasmalysis reactor.

12. The energy production device of claim 1, wherein a filtration device is arranged downstream of the plasmalysis reactor, and wherein the filtration device is configured to separate the H.sub.2 from other residual gases.

13. The energy production device of claim 12, further comprising: a return pipe that extends between the filtration device and the plasmalysis reactor, configured to reinject residual gases collected in the filtration device into the reactor.

14. The energy production device according of claim 1, wherein the energy conversion unit is a domestic, collective or industrial heating facility or an industrial process heat source.

15. The energy production device of claim 1, wherein the energy conversion unit comprises a gas turbine or an internal combustion engine, mechanically coupled to an electric generator.

16. The energy production device of claim 1, wherein the energy conversion unit comprises a fuel cell.

17. The energy production device of claim 16, comprising a dihydrogen filtration member arranged fluidically between the compression device (14) and the storage tank (12), and wherein the dihydrogen filtration member is configured to guarantee a purity of the H.sub.2 compatible with operation of a fuel cell.

18. A method for operating the energy production device of claim 1, comprising: controlling the dihydrogen production unit by the control module by modulating production of H.sub.2 by operating the energy conversion unit.

19. The method of claim 18, wherein the modulating is carried out in binary mode, and wherein the plasmalysis reactor is started only when the information relating to the H.sub.2 present in the dihydrogen distribution area has an outgoing value from a predefined value range.

20. The method of claim 19, wherein the modulating comprises adjusting (i) a flow rate and/or pressure of the hydrocarbon gas entering the dihydrogen production unit and/or (ii) operating power of the dihydrogen production unit.

Description

[0069] Other features and advantages of the invention will appear both from the description which follows and from several exemplary embodiments, which are given for illustrative purposes and without limitation with reference to the appended schematic drawings, in which:

[0070] FIG. 1 is a schematic representation of a first embodiment of an energy production device implementing in particular a unit for producing dihydrogen by plasmalysis and an energy conversion unit of the heating facility type;

[0071] FIG. 2 is a schematic representation of a second embodiment of an energy production device which differs from FIG. 1 in that the energy conversion unit is of the gas turbine type;

[0072] FIG. 3 is a schematic representation of a third embodiment of an energy production device which differs from FIG. 1 in that the energy conversion unit is of the fuel cell type;

[0073] FIG. 4 is a schematic representation of a microwave radiation cavity of the dihydrogen production unit of FIG. 1, seen in a plane perpendicular to a longitudinal axis of the plasma;

[0074] FIG. 5 is a view of details of the microwave radiation cavity of FIG. 3 with a nozzle and a pipe of the dihydrogen production unit of FIG. 1, seen in a plane comprising the longitudinal axis of the plasma;

[0075] FIG. 6 is a schematic view showing dimensions of the resonant microwave radiation cavity of the plasmalysis reactor.

[0076] It should first of all be noted that while the figures set out the invention in detail for its implementation, they may of course be used to better define the invention where appropriate. It should also be noted that, in all of the figures, similar elements and/or elements fulfilling the same function are indicated by the same numbering.

[0077] FIG. 1 shows an energy production device 100 which, according to the invention, mainly comprises a device for supplying hydrocarbon gas 1, an energy conversion unit 2 and a dihydrogen production unit 3 arranged fluidically between the device for supplying hydrocarbon gas 1 and the energy conversion unit 2, the dihydrogen production unit 3 comprising at least one plasmalysis reactor 5 configured to produce at least dihydrogen from hydrocarbon gas.

[0078] According to the invention, the energy production device 100 further comprises a control module 200 configured to generate a control instruction for the dihydrogen production unit as a function of information relating to the dihydrogen present in a dihydrogen distribution area 6 fluidically arranged between the plasmalysis reactor 5 and the energy conversion unit 2.

[0079] Plasmalysis is a method that makes it possible to break down the hydrocarbon gas into solid carbon C.sub.(S) and dihydrogen gas H2.sub.(g) by means of a plasma generated by microwave radiation. The hydrocarbon gas can be methane CH.sub.4, propane C.sub.3H.sub.8, butane C.sub.4H.sub.10 and its isomers, and/or natural gas or biomethane. Natural gas may predominantly comprise methane CH.sub.4, and in a lesser proportion of propane C.sub.3H.sub.8 and/or butane C.sub.4H.sub.10 and its isomers. When the hydrocarbon gas is methane, the plasmalysis reaction is written:

[00001]$\begin{array}{cc}C{H}_4\stackrel{\mathrm{Plasma}}{.fwdarw.}2H_{2\left(g\right)}+C_{\left(s\right)}& \left[\mathrm{Math}\right]\end{array}$

[0080] The plasmalysis method makes it possible to generate dihydrogen according to a completely decarbonized process, that is to say without carbon dioxide emissions, with dihydrogen gas and solid carbon forming reaction products resulting from plasmalysis.

[0081] The hydrocarbon gas required for the reaction of plasmalysis that occurs in the plasmalysis reactor 5 is supplied by the supply device 1. In the example shown, the supply device 1 comprises at least one storage device 8 which can be supplied for example by tanker trucks and/or be replaced when it is empty.

[0082] In an embodiment not shown, the hydrocarbon gas supply device is a terminal part of a gas hydrocarbon distribution network, ensuring just-in-time distribution, without a storage device. The distribution network makes it possible to convey the hydrocarbon gas from gas terminals. The distribution network is thus for example a gas distribution network for industrial, collective or household uses.

[0083] The dihydrogen production unit also comprises a controllable valve 10 arranged on this terminal part of the hydrocarbon gas distribution network, or in other words on a connection duct fluidically arranged between the device for supplying hydrocarbon gas 1 and the plasmalysis reactor 5. The controllable valve 10 is configured to receive a control instruction of the above-mentioned control unit 200, and to allow, depending on this instruction to control the arrival or non-arrival of hydrocarbon gas in the plasmalysis reactor, and where appropriate, depending on this control instruction, a larger or smaller intake of hydrocarbon gas.

[0084] The dihydrogen distribution area 6 is configured to fluidically connect an outlet of the plasmalysis reactor and an inlet of the energy conversion unit. In the example shown in FIG. 1, this dihydrogen distribution area 6 comprises a dihydrogen storage assembly sized to recover and store the dihydrogen produced by the plasmalysis reactor, before its injection into the energy conversion unit. Such a storage assembly makes it possible in particular to ensure that the dihydrogen supplied to the energy conversion unit is distributed at a suitable pressure and flow rate for the correct operation of the energy conversion unit. Here, the storage assembly comprises a storage tank 12, a compression device, or compressor, 14 upstream from the storage tank, such that the compressor is arranged fluidically between the plasmalysis reactor 5 and the storage tank 12 in order to allow the dihydrogen to be stored at an appropriate pressure in the storage tank, and an expander 15 downstream of the storage tank, so that the expander is arranged fluidically between the storage tank 12 and the energy conversion unit 2, in order to allow the energy conversion unit to be supplied with dihydrogen at an appropriate pressure.

[0085] The dihydrogen distribution area 6, and more particularly here the storage tank 12, is equipped with a measuring device allowing information relating to the presence of dihydrogen in the dihydrogen distribution area to be recorded. More particularly here, the measuring device consists of a gauge 16 able to raise the pressure of the dihydrogen present in the storage tank. The gauge 16 is connected to the control unit 200, and it is in particular based on this information relating to the presence of dihydrogen in the dihydrogen distribution area that the control unit generates a control instruction for the dihydrogen production unit, and for example a controllable valve control unit as previously mentioned.

[0086] As mentioned above, the dihydrogen production unit 3 is arranged between the device for supplying hydrocarbon gas 1 and the energy conversion unit 2 so as to convert the hydrocarbon gas from, for example, the utility gas network into dihydrogen usable as fuel for the energy conversion unit.

[0087] This energy conversion unit 2 is here a heating facility capable of converting dihydrogen into thermal energy, and more particularly here an industrial heating plant, requiring to be supplied with dihydrogen with a high flow rate. Such a need for dihydrogen supply is in particular ensured by the presence of the storage assembly in the dihydrogen distribution area 6.

[0088] The heating plant here comprises a system for controlling the injected gas 18, a flame burner 20 with a flame or catalysis suitable for the combustion of dihydrogen, a heating body 22 and a system for distributing heat 23 either by water, by air or by another heat transfer fluid.

[0089] Alternatively, an energy production device as previously mentioned could include, as an energy conversion unit, an industrial process heat source, here again requiring high-flow dihydrogen, but it could also include an individual or collective heating facility.

[0090] The plasmalysis reactor is more particularly described below with reference to FIGS. 4 to 6.

[0091] The plasmalysis reactor 5 comprises at least one microwave radiation cavity 24 formed in a block 26 made of metal. The hydrocarbon gas coming from the supply device 1 is injected into the microwave radiation cavity 24 and the microwave radiation is also guided in the microwave radiation cavity 24. The microwave radiation cavity 24 is configured to receive at least in part the plasma 28. Thus, the resonant microwave radiation cavity 24 allows very effective coupling of the microwave radiation to the plasma 28.

[0092] The microwave radiation cavity 24 can be coupled with a waveguide specific to the frequencies of between 850 MHz and 6 GHz, preferably equal to 896 MHz, 915 MHz, 922 MHz, 2.45 GHz or 5.8 GHz. It is resonant, meaning that microwave radiation is 100% reflected by at least one block wall 26 delimiting the microwave radiation cavity 24, when there is no plasma 28 present in the microwave radiation cavity 24.

[0093] As shown in FIG. 6, the dimensions of an active discharge zone 25 of the resonant microwave radiation cavity 24 are defined by the frequency used. The active discharge zone 25 is the zone where the plasma 28 forms. The width L1 of the resonant microwave radiation cavity 24 is defined by the frequency used and by the type of waveguide, the height H1 of the resonant microwave radiation cavity 24 is equal to half the width L1 of this microwave radiation cavity 24 and the width L2 of the active discharge zone 25 is less than or equal to the height H1 of the microwave radiation cavity 24. Due to the geometry of the resonant microwave cavity, the microwaves concentrate at the center of the cavity to form a distribution of the electromagnetic field with a power density sufficient to ionize the hydrocarbon gas flow. The active discharge zone 25, otherwise called the plasma zone, is the zone where the interaction between the electromagnetic field and the ionized hydrocarbon gas stream is optimal. The plasma 28 is initiated by introducing an ignition device 30 at the center of the active discharge zone 25.

[0094] The injection of the hydrocarbon gas into the microwave radiation cavity 24 is carried out by an injection device 32 of the plasmalysis reactor 5. More specifically shown in FIG. 4, the injection device 32 comprises at least one head 34, here two heads 34, coupled to at least one inlet 36 of the microwave radiation cavity 24. The head 34 makes it possible to create a hydrocarbon gas flow coming from the supply device 1.

[0095] The inlet 36 is arranged tangentially to an elongation direction of the plasma 28. The inlet 36 is also arranged tangentially to a wall delimiting the microwave radiation cavity 24. This configuration then makes it possible to create a vortex of the gas hydrocarbon stream 38 in the microwave radiation cavity 24 as is shown in FIG. 4 and in FIG. 5. The vortex contributes to the stability of the plasma 28.

[0096] The hydrocarbon gas stream 38 ionized by the microwave radiation produces the plasma 28. The gas hydrocarbon stream 38 of the vortex producing the plasma is also intended to undergo plasmalysis. It is understood in this context that the gas used to form the plasma and the gas which undergoes plasmalysis are identical. In other words, a single gas from a single source makes it possible to produce the plasma, to produce dihydrogen and solid carbon. In other words, the hydrocarbon gas serves both as plasma gas and plasmalysis reagent.

[0097] With reference to FIG. 1, the plasmalysis reactor 5 comprises a microwave radiation generator 40 which makes it possible to create a plasma in the microwave radiation cavity 24. The microwave radiation generator 40 may be a magnetron microwave radiation generator or a semiconductor microwave generator, also called a solid-state microwave radiation generator.

[0098] In an embodiment not shown, the microwave radiation generator 40 is cooled by a water and/or air cooling device. This makes it possible to keep the microwave radiation generator 40 at an optimum operating temperature.

[0099] The microwave radiation generator 40 is configured to generate microwave radiation whose power is between 0.1 kW and 100 kW at a frequency comprised between 850 MHz and 6 GHz, preferentially equal to 896 MHz, 915 MHz, 922 MHz, 2.45 GHz or 5.8 GHz.

[0100] As can be seen in particular in FIG. 1, the microwave radiation is directed toward the microwave radiation cavity 24 by a microwave transmission guide 42 coupled to the microwave radiation generator 40. The microwave transmission guide 42 is a rectangular or cylindrical waveguide or a coaxial cable.

[0101] A microwave radiation insulator 44 is arranged between the microwave radiation generator 40 and the microwave transmission guide 42, that is to say at the coupling between the microwave generator 40 and the microwave transmission guide 42. The insulator 44 prevents microwave radiation not absorbed by the plasma 28 from returning to the microwave radiation generator 40 by reflections in the microwave transmission guide 42.

[0102] As has been mentioned, the plasmalysis reactor 5 comprises a device 30 for igniting the plasma 28. The ignition device 30 is an electromechanical mechanism comprising a metal tip 45 and an actuator 46 which moves the metal tip 45 between a position outside the cavity of microwave radiation and a position in the microwave radiation cavity. The metal tip 45 is therefore retractable.

[0103] Thus, to initiate the plasma, the microwave radiation generated by the microwave radiation generator 40 is transmitted to the microwave radiation cavity 24 wherein the hydrocarbon gas is injected tangentially to the walls of the microwave radiation cavity 24 to form a vortex of a hydrocarbon gas flow. As soon as the power of the microwave radiation required is reached, the ignition of the plasma is carried out by the ignition device 30, the metal tip 45 of which remains for less than a second in the active discharge zone of the microwave radiation cavity 24. The hydrocarbon gas stream 38 itself serves to produce the plasma 28, thus undergoing the plasmalysis reaction. After the plasma priming phase, the plasma is kept and stabilized by the microwave flow and the gas hydrocarbon stream in vortex.

[0104] The pressure in the microwave radiation cavity 24 is greater than or equal to atmospheric pressure. More generally, the pressure prevailing within at least part of the dihydrogen production unit 3 is greater than or equal to atmospheric pressure. Advantageously, the pressure prevailing within at least part of the dihydrogen production unit 3 is greater than atmospheric pressure.

[0105] With reference to FIG. 1 and to FIG. 5, an outlet 48 of the microwave radiation cavity 24 is extended by a nozzle 50 composed at least in part of ceramic and/or metal. The nozzle 50 is used to contain the plasma. The nozzle 50 is also used to ensure the continuity of the plasmalysis reaction by protecting the reaction products, in particular the products derived from plasmalysis, against rapid cooling at the outlet 48 of microwave radiation cavity 24. In other words, the nozzle 50 therefore allows a gradual reduction in the temperature of the reaction products, in particular products derived from the plasmalysis at the outlet 48 of the microwave radiation cavity 24.

[0106] The plasma 28, once created, extends both in the microwave radiation cavity 24 and in the nozzle 50 along a longitudinal axis L. Thus, the nozzle extends from the outlet 48 of the microwave radiation cavity 24 in a direction opposite the microwave radiation cavity along the longitudinal axis L.

[0107] With reference to FIG. 1, the plasmalysis reactor 5 comprises a pipe 52 which extends from a vicinity of the outlet 48 of the microwave radiation cavity 24 in a direction opposite to the microwave radiation cavity 24 along the longitudinal axis L. The dimension of the pipe 52 measured along the longitudinal axis L is greater than the dimension of the nozzle 50 measured along the longitudinal axis L. The pipe completely surrounds the nozzle 50.

[0108] A first part 54 of the pipe 52 has a suitable shape, concentric to the nozzle 50. Thus, a thermal insulation chamber of the plasma 28 is delimited between an external face of the nozzle 50 and an internal face of the first part 54 of the pipe 52. The chamber makes it possible to thermally isolate the plasma 28 in order to limit, or even eliminate, temperature inhomogeneities within the plasma 28, in particular at its periphery.

[0109] The pipe 52 comprises a second part 56 which extends the first part 54 of the pipe along an axis parallel to the longitudinal axis L of the plasma 28. The second part 56 of the pipe 52 delimits a cooling chamber 58. Thus, the cooling chamber cools the reaction products. The solidification of the carbon is thus improved. Reaction products combine methane not having been decomposed during plasmalysis, the products derived from plasmalysis, that is to say dihydrogen gas and solid carbon.

[0110] In the embodiment of the invention in FIG. 1, the second part 56 of the pipe 52 comprises on its inner face a plurality of fins 60 that extend radially from the internal face of the second part 56 of the pipe 52 towards the center of the pipe and which are thermally coupled with the internal face of the second part of the pipe 52. Thus, the heat exchanges with the reaction products coming into contact with the fins 60 are improved, facilitating solidification of the carbon produced by plasmalysis.

[0111] A fluid circulation device 62 is arranged against an outer wall of the second part 56 of the pipe 52 so as to at least partially cool the second part 56 of the pipe 52. Thus, the cooling of the reaction products in the cooling chamber 58 is ensured by convective and conductive exchanges with at least a part of the internal face of the second part 56 of the pipe 52 which is cooled by the fluid circulation device 62. The separation of the dihydrogen from the other reaction products is improved by this cooling. When the pipe 52 further comprises the fins 60 which are then also cooled by thermal conduction, the separation is even more efficient. This is particularly very useful when flowing from the reaction product stream to a separation device 64 equipping the dihydrogen production unit 3.

[0112] The separation device 64 notably comprises a vortex separator element.

[0113] The separator element is configured to suck in the flow of cooled reaction products from the cooling chamber 58. The cooled solid carbon is deposited either on a bottom of the separator element, or on an inner surface of a wall of the separator element. Other solid particles are present in the flow of cooled reaction products and also are deposited at the same locations as the solid carbon.

[0114] The solid carbon thus recovered is stored in a recovery device 66 and can be supported by the same vehicle which changes or replenishes the storage devices 8 of the supply device if necessary. The solid carbon can then be recycled for various industrial uses.

[0115] The dihydrogen exiting the separation device 64 then circulates in the dihydrogen distribution area 6 fluidically arranged between the plasmalysis reactor 5 and the energy conversion unit 2.

[0116] In the first embodiment shown in FIG. 1, the dihydrogen distribution area 6 is provided with the storage assembly here comprising the storage tank 12, the compressor 14 and the expander 15, and the dihydrogen can be stored at a pressure that can range up to about 900 bars before being expanded to the appropriate pressure for the supply of the energy conversion unit 2. Thus, it is possible to meet the consumer's demand for dihydrogen in all circumstances.

[0117] As mentioned above, the control module 200 of the energy production device is configured according to the invention to generate a control instruction for the dihydrogen production unit as a function of a piece of information relating to the dihydrogen present in a dihydrogen distribution area fluidically arranged between the plasmalysis reactor and the energy conversion unit.

[0118] More particularly, in the shown example, the control module 200 retrieves information and is able to generate one or more control instructions to different components of the dihydrogen production unit, among them the controllable valve 10, the ignition device 30 of the plasmalysis reactor 5, the microwave radiation generator 40, and the compressor 14.

[0119] In an independent manner, by only performing a specific control instruction, or in complementary fashion, by performing several control instructions simultaneously, the control module 200 can control the supply of hydrocarbon gas by controlling the operation of the controllable valve 10, or control the operation of the plasmalysis reactor by controlling the microwave radiation device 40 and/or by controlling the ignition device 30, or control the operation of the storage assembly by controlling the compressor 14.

[0120] These control instructions may consist of a binary operation instruction, of the start-and-stop type, or consist of an operation instruction adjusted, with a production of dihydrogen of variable quantity and adjusted to demand.

[0121] It is understood that the presence of this control module makes it possible to operate the dihydrogen production unit as a function of the need for the energy conversion unit, in order to adjust the energy consumption of the device without reducing the service of the energy conversion unit.

[0122] A first example of a method of operating the energy production device can be as follows. Energy demand, here thermal, is formed at the energy conversion unit. The result is a drawdown of dihydrogen, and the volume of dihydrogen present in the storage vessel 12 is reduced. The dihydrogen production unit remains off, in a shutdown mode that is not energy-consuming, until the pressure of the dihydrogen present in the storage tank 12, measured by the gauge 16, has a value greater than a predefined threshold value, for example on the order of 10 bars. As soon as the pressure of the dihydrogen becomes less than this predefined threshold value, the control module transmits activation information to one of the components likely to be driven by the control module. By way of example, simultaneously, the controllable valve 10 is opened to allow the passage of hydrocarbon gas, while the ignition device 30 and the microwave radiation generator 40 are actuated. Here, it is in the binary operating mode mentioned above. A control instruction corresponding to the closing or placing of these components on standby is subsequently generated by the control module when the storage tank is again filled with dihydrogen.

[0123] A second example of a method of operating the energy production device can be as follows. Once again, energy demand, here thermal, is formed at the energy conversion unit. The result is a drawdown of dihydrogen, and the volume of dihydrogen present in the storage vessel 12 is reduced. The dihydrogen production unit is then controlled to operate initially in a first mode, corresponding to a reduced production mode of dihydrogen, for example by reducing the gas inlet flow rate by limiting the opening of the controllable valve 10 and limiting the amount of microwave radiation in the plasmalysis reactor by a reduced load operation of the microwave radiation generator. This first reduced dihydrogen production mode is implemented as long as the pressure of the dihydrogen present in the storage tank 12, measured by the gauge 16, has a value greater than a predefined threshold value, for example on the order of 10 bars. As soon as the pressure of the dihydrogen becomes less than this predefined threshold value, the control module modifies the control instructions to modulate the operation of the dihydrogen production unit and to operate it at full speed. Here, it is in the modular operating mode mentioned above.

[0124] A second embodiment is shown in FIG. 2 and differs from what has been described for the first embodiment in that the energy conversion unit 2 comprises a gas turbine.

[0125] Downstream of the expander 15, a dihydrogen combustion chamber 70 makes it possible to create sufficient energy to drive a motor shaft 72 and an associated electric generator, and thus to convert the energy of the dihydrogen into mechanical or electrical energy.

[0126] Alternatively, provision may be made for the energy conversion unit to be an internal combustion engine, it being understood that the structure of the dihydrogen production unit remains the same as that which has just been described in this third embodiment, here also with a dihydrogen distribution area 6 which comprises a compressor, a storage tank and an expander.

[0127] The operation of the gas turbine, or of the internal combustion engine, involves supplying a high-speed dihydrogen so that the dihydrogen production unit is in accordance with the first embodiment equipped with a compressor and a storage tank making it possible to store the dihydrogen produced up to a pressure of 900 bars.

[0128] A third embodiment is shown in FIG. 3 and differs from what has been described for the first embodiment in that the energy conversion unit 2 here comprises a fuel cell 73. As schematically shown, the fuel cell receives dihydrogen and air at the inlet, and is configured to deliver electricity to electrical equipment and/or an electrical network 75. By way of non-limiting examples shown in FIG. 3, the electrical equipment downstream of the fuel cell is the microwave radiation generator 40, in order to allow an autonomous power supply thereof, and an electrical energy storage member 74. Here, an appropriate current converter 76 is arranged between the output of the fuel cell 73 and the electrical equipment and network.

[0129] The proper operation of the fuel cell requires a greater level of purity of the dihydrogen than was necessary for the other types of energy conversion units previously described such as boilers for example. In this context, the energy production device according to this third embodiment is equipped with filtration means.

[0130] As shown in FIG. 3, the energy production device according to this third embodiment can in particular be equipped with a filtration device 65 arranged exiting the plasmalysis reactor. The gases collected exiting the plasmalysis reactor 5, and in particular after being passed through the separation device 64, pass into a filter of this filtration device which is configured to separate the dihydrogen from the other gaseous products, which may in particular be, as shown in FIG. 3, reinjected into the reactor for a new plasmalysis, via a return line 67. The dihydrogen collected exiting the filtration device 65 is directed toward the dihydrogen distribution area 6 and more particularly here to the compressor 14 before being stored in the storage tank 12.

[0131] In other words, a filtration is carried out downstream of the plasmalysis reactor which tends to distinguish, within the plasmalysis reaction products, the dihydrogen capable of being directed toward the fuel cell and the other residual gases, in minuscule quantities. These residual gases may for example be methane which has not undergone total decarbonization and any secondary reaction products of ethane, ethylene, etc. All the residual gases are reinjected into the plasmalysis reactor to break them down completely.

[0132] Furthermore, the energy production device according to the third embodiment, that is to say with an energy conversion unit comprising a fuel cell, can in particular be equipped with a dihydrogen filtering member 69 which is configured to increase the purity of the dihydrogen passing through this dihydrogen filtering member 69. In this way, it is intended to obtain a dihydrogen purity level compatible with the operation of a fuel cell 73.

[0133] As shown in FIG. 3, the dihydrogen filtering member 69 is arranged fluidically between the compression device 14 and the storage tank 12.

[0134] It should be noted that if the filtration means, that is to say the filtration device 65 and the filtration member 69, are shown only in the third embodiment, they could, without departing from the context of the invention, equip a production device according to other embodiments of the invention previously described, even if such device implements dihydrogen burners, and/or a turbine and/or an internal combustion engine within the energy conversion units, and thus a degree of purity of the dihydrogen arriving in these energy conversion units is not essential.

[0135] Furthermore, the device according to the third embodiment differs here from the foregoing in that a storage cylinder 78 and an associated expander 79 participate in forming the supply device 1. It should be noted that this embodiment of the supply device could be different and be replaced by the embodiments described previously, and that more generally, any one the embodiments described could be implemented in each embodiment without departing from the context of the invention.

[0136] Of course, the invention is not limited to the examples that have just been described, and numerous modifications can be made to these examples without departing from the scope of the invention.

[0137] By way of non-limiting example, a filtration system could be provided upstream from the plasmalysis reactor, that is to say between the supply device and the plasmalysis reactor, which in particular makes it possible to purify the hydrocarbon gas intended to be injected into the microwave radiation cavity in order to improve the performance of plasmalysis. In particular, when the inlet gas is natural gas coming from a gas network composed mainly of methane, filtering unwanted components such as nitrogen, carbon monoxide or carbon dioxide can thus be carried out before injection into the reactor with plasmalysis.

[0138] The invention, as has just been described, clearly achieves the goal that it was set, and makes it possible to propose an energy production device, whether thermal, electrical or mechanical, which is configured to use a supply of hydrocarbon gas, which may in particular consist of a city gas network and dihydrogen burners, which are more ecological, owing to the presence of a dihydrogen production unit by plasmalysis combined with a control module capable of controlling the operation of this production unit in order to efficiently, but economically, meet demand for energy production.