High-temperature electrolyser systems optimized with intermediate circuit recovery modules

Abstract

The invention relates to a system comprising an HTE electrolyser (1), a first water vapor supply line (2), a first dihydrogen discharge line (4), a second dioxygen discharge line (3) and a first heat exchange module (5) configured to ensure heat exchange between the first water vapor supply line (2) and the first dihydrogen discharge line (4), characterized in that the system comprises a first module for recovering thermal energy from dihydrogen at the outlet of the first heat exchange module (5) for the first supply line (2), the recovery module comprising a first intermediate exchanger (6) arranged on the first discharge line (4) downstream of the first heat exchange module (5) and configured to transfer thermal energy from the dihydrogen to an intermediate fluid, and a first intermediate water steam generator (50) arranged on the first water vapor supply line (2) and configured to transfer thermal energy from the intermediate fluid to liquid water.

Description

[Technical field]

[0001] The present invention relates to the field of solid oxide fuel cells (SOFC) and high temperature electrolysis (HTE) or high temperature steam electrolysis (HTSE) solid oxide fuel cells (SOFC) and also solid oxide electrolysis cells (SOEC). The present invention is applied in particular to optimise the energy consumption of SOEC electrolyser systems. [Background technology]

[0002] Water electrolysis is an electrolytic reaction in which an electric current is used to split water into the gases dioxygen and dihydrogen according to the reaction H2O→H2+1 / 2O2.

[0003] To achieve the electrolysis of water, it is advantageous to carry out the reaction at high temperatures, typically between 600 and 950 °C, since part of the energy required for the reaction can be provided by heat, which is cheaper than electricity, and the activation of the reaction is more effective at high temperatures and does not require a catalyst. A solid oxide electrolysis cell (SOEC) comprises a first porous conductive electrode or "cathode" intended in particular to be supplied with water vapor to produce dihydrogen, a second porous conductive electrode or "anode" to which the dioxygen produced by the electrolysis of water injected into the cathode escapes, and a solid oxide membrane (dense electrolyte) sandwiched between the cathode and the anode, which membrane is anionically conductive to high temperatures, typically above 600 °C. By heating the cell to at least this temperature and injecting a current I between the cathode and the anode, reduction of water takes place at the cathode to produce dihydrogen (H2) at the cathode and dioxygen at the anode. To carry out high-temperature electrolysis, it is known to use SOEC electrolysers, which are composed of a stack of basic units, each of which comprises a solid oxide electrolysis cell of three layers, anode / electrolyte / cathode, superimposed on one another, and an interconnecting plate made of a metal alloy, also called a bipolar plate or interconnector. The interconnector has the function of ensuring both the passage of electric current and the circulation of gases in the vicinity of each cell (injected steam, extracted water and oxygen in HTE electrolysers, injected air and hydrogen, extracted water in SOFC cells), and of separating the anode and cathode sections, which are the gas circulation compartments on the anode and cathode sides of the cell, respectively.

[0004] To achieve water vapor electrolysis in the high temperature HTE, water vapor, H2O, is injected into the cathode section.

[0005] Under the influence of an electric current applied to the cell, at the interface between the hydrogen electrode (cathode) and the electrolyte, a separation of water molecules in the form of water vapor takes place, which produces dihydrogen gas H2 and oxygen ions. The dihydrogen is collected and discharged from the outlet of the hydrogen compartment. The oxygen ions migrate through the electrolyte and recombine into dioxygen O2 at the interface between the electrolyte and the oxygen electrode (anode).

[0006] For effective performance of electrolysis by the stack, the stack is brought to a temperature higher than 600° C., typically between 600° C. and 950° C., the gas supply is turned on at a constant flow rate, and a power supply is connected between the two terminals of the stack to circulate a current I therethrough.

[0007] The yield of electricity to hydrogen conversion is a key point to ensure the competitiveness of the technology. Strictly speaking, the power consumption mainly occurs during the electrolysis reaction, but almost 30% of the power consumption of an electrolyzer comes from the fluid thermal / hydraulic management system, i.e. the architecture external to the electrolyzer and the management of the fluids and thermal energy within this architecture.

[0008] The evaporation of the water used in the electrolyser is the largest energy consumption of this thermal / hydraulic management system. Traditionally, this function is ensured by an electric water vapor generator, which consumes 20% of the overall consumption of the electrolyser.

[0009] Moreover, a significant part of the energy is generally rejected to the surrounding environment. For example, during the hydrogen drying and compression stages, the water / hydrogen mixture needs to be deeply cooled to allow condensation of the water present in the mixture. This condensation mainly takes place at temperatures below the evaporation temperature of the water at the inlet of the electrolyzer, which means that only a small part of this condensation energy can be used.

[0010] It is therefore necessary to minimize this consumption by optimizing the electrolyser system architecture and fluid management. Summary of the Invention [Problem to be solved by the invention]

[0011] The object of the present invention is therefore to propose a high-temperature electrolyser system optimized with an intermediate circuit recovery module.

[0012] Other objects, features and advantages of the present invention will become apparent from a consideration of the following description and the accompanying drawings, and it will be understood that other advantages may be incorporated. [Means for solving the problem]

[0013] To this end, according to one embodiment, High temperature electrolyzer (HTE) and a first supply line for the electrolyzer configured to supply water vapor to the electrolyzer; a first line for discharging the electrolyzer configured to discharge dihydrogen from the electrolyzer; a second line for discharging the electrolytic cell, configured to discharge dioxygen from the electrolytic cell; a first heat exchange module configured to ensure heat exchange between the first water vapor supply line and the first dihydrogen discharge line; A system is provided comprising:

[0014] The system is characterized in that it comprises a first module for recovering thermal energy from dihydrogen at an outlet of a first heat exchange module for a first water vapor supply line, the recovery module comprising: a first intermediate exchanger disposed on the first discharge line downstream of the first heat exchange module and configured to transfer thermal energy from the dihydrogen to the intermediate fluid; a first intermediate steam generator disposed on the first steam supply line and configured to transfer thermal energy from the intermediate fluid to the liquid water; a first intermediate fluid circuit configured to receive an intermediate fluid and to ensure a fluid connection between the first intermediate exchanger and the first intermediate steam generator; Equipped with.

[0015] This arrangement allows the recovery of heat from the dihydrogen produced by the electrolyser for the production of water steam. With this system, the recovery module allows both dihydrogen and water steam production. Thus, the electricity consumption of the system is significantly reduced.

[0016] The system therefore uses heat from the dihydrogen at the outlet of the electrolyser, preferably after the first heat exchange module, so that the thermal rejection of the dihydrogen is carried out at low temperature by the steam generator via an intermediate circuit. The heat recovered from the dihydrogen is reinjected, preferably upstream of the electric steam generator, at a temperature higher than the evaporation temperature of the water in the steam supply line.

[0017] Advantageously, the use of an intermediate circuit between the first dihydrogen discharge line and the intermediate steam generator makes it possible to have a remote steam generator rather than an exchanger between the dihydrogen discharge line through which water and dihydrogen circulate. The intermediate circuit has a good modularity of the recovery module, since it also makes it possible to consider recovering heat quantities elsewhere in the system, for example downstream of the dihydrogen discharge line or downstream of the dioxygen discharge line, without complicating the structure of the recovery module.

[0018] The system therefore makes it possible to reduce the electrical consumption of the system by increasing the recovered heat power.

[0019] The system according to the present invention has an overall yield improvement of 3% over the conventional configuration.

[0020] The objects, aims, features and advantages of the present invention will become best apparent from the following detailed description of the embodiments illustrated in the accompanying drawings, in which: [Brief description of the drawings]

[0021] [Figure 1]FIG. 1 is a functional diagram illustrating a system according to a first embodiment of the present invention. [Diagram 2] FIG. 2 is a functional diagram representing an intermediate circuit. [Diagram 3] FIG. 4 is a functional diagram illustrating a system according to a second embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] The drawings are given by way of example and not of limitation of the invention: they constitute principle schematic diagrams intended to facilitate understanding of the invention and are not necessarily to the scale of actual application.

[0023] Before commencing a detailed discussion of embodiments of the present invention, optional features that may optionally be used in conjunction or alternatively are described below.

[0024] According to one example, the system comprises a third module for recovering thermal energy from dihydrogen at the outlet of the first heat exchange module 5 for the first water vapor supply line 2, the third recovery module comprising a heat pump and an intermediate circuit, The intermediate circuit is a second intermediate exchanger 7 arranged on the first discharge line 2 downstream of the first heat exchange module 5 and configured to transfer thermal energy from the dihydrogen to an intermediate fluid; a third intermediate fluid circuit 32 configured to receive an intermediate fluid and to ensure a fluid connection between the second intermediate exchanger 7 and the heat pump; Equipped with The heat pump is a fluid circuit 27 configured to receive a heat transfer fluid; an evaporator 25 arranged on the intermediate fluid circuit 32 downstream of the second intermediate exchanger 7 and configured to transfer thermal energy from the intermediate fluid to a heat transfer fluid; a compressor 26 configured to compress the heat transfer fluid; a condenser 23 arranged on the first water vapor supply line 2 upstream of the first heat exchange module 5 and configured to transfer thermal energy from the heat transfer fluid to liquid water; a reducer 24 configured to reduce the heat transfer fluid; Equipped with The fluid circuit 27 is configured to fluidly connect the evaporator 25 to the compressor 26, to fluidly connect the compressor 26 to the condenser 23, to fluidly connect the condenser 23 to the reducer 24, and to fluidly connect the reducer 24 to the evaporator 25.

[0025] According to one example, the system comprises a fifth intermediate exchanger 12 arranged on the first dihydrogen discharge line 4 downstream of the second intermediate exchanger 7 in parallel with the second intermediate exchanger 7 on the third intermediate fluid circuit 32 and configured to transfer thermal energy from the dihydrogen to the intermediate fluid.

[0026] According to one example, the system comprises a sixth intermediate exchanger 15 arranged on the first dihydrogen discharge line 4 downstream of the fifth intermediate exchanger 12 in parallel with the second intermediate exchanger 7 and the fifth intermediate exchanger 12 on the intermediate fluid circuit 32 and configured to transfer thermal energy from the dihydrogen to the intermediate fluid.

[0027] According to one example, the system comprises an electric steam generator 28 arranged on the first steam supply line 2 upstream of the first heat exchange module 5 .

[0028] According to one example, the electric water vapor generator 28 is arranged downstream of the first water vapor generator 50 , preferably downstream of the condenser 23 .

[0029] According to one example, the system comprises a second vacuum module for recovering thermal energy from dihydrogen at the outlet of the first heat exchange module 5 for the first water vapor supply line 2, the vacuum recovery module comprising: a third intermediate exchanger 8 arranged on the first discharge line 4 downstream of the first heat exchange module 5 and configured to transfer thermal energy from the dihydrogen to the intermediate fluid; a reducer 40 and a compressor 41 arranged on the first water vapor supply line 2 upstream of the first heat exchange module 5 and which together define a reduced pressure section of the first water vapor supply line 2; a second intermediate steam generator 60 arranged on the reduced pressure section of the first steam supply line 2 and configured to transfer thermal energy from the intermediate fluid to liquid water; a second intermediate fluid circuit configured to receive an intermediate fluid and to ensure a fluid connection between the third intermediate exchanger (8) and the second steam generator (60); Equipped with.

[0030] According to one example, the electric steam generator 28 is arranged downstream of the second steam generator 60 , preferably on the reduced pressure section downstream of the condenser 23 .

[0031] According to one example, the first water vapor supply line 2 comprises a main branch in which the water vapor generator 50 is arranged and a reduced pressure branch comprising a reduced pressure portion, the main branch and the reduced pressure branch being arranged in parallel.

[0032] According to one example, the system comprises a second electrolyser supply line 10 configured to supply air to the electrolyser 1 .

[0033] According to one example, the system comprises a second heat exchange module 11 configured to ensure heat exchange between the second air supply line 10 and the second dioxygen exhaust line 3 .

[0034] According to one example, the system comprises a fourth intermediate heat exchanger 9 arranged in parallel with the first intermediate exchanger 6 between the second dioxygen discharge line 3 and the first intermediate fluid circuit.

[0035] According to one example, the system comprises a seventh intermediate exchanger 29 arranged on the second dioxygen discharge line 3 downstream of the first heat exchanger 9 in parallel with the second intermediate exchanger 7 on the third intermediate fluid circuit 32 and configured to transfer thermal energy from the dioxygen to the intermediate fluid.

[0036] According to an option, the system comprises at least one first air cooler or a second heat exchanger arranged on the first dihydrogen discharge line downstream of the first intermediate exchanger.

[0037] According to an option, the system comprises at least one second air cooler or a third heat exchanger arranged on the first dihydrogen exhaust line downstream of the second heat exchanger.

[0038] According to one example, the system includes a liquid / gas separator downstream of the first air cooler and upstream of the second intermediate exchanger.

[0039] The upstream and downstream, inlet, and outlet at any given point are taken with reference to the direction of circulation of the fluid.

[0040] By a parameter is "substantially equal to / greater than / less than" a given value, this means that the parameter is plus or minus 10% of the given value, or even plus or minus 5%, equal to / greater than / less than this value.

[0041] The numbering of n, first, second, third, etc., is meant to be without limitation or association with the necessity of having n-1 or n+1.

[0042] The system according to the invention comprises a high temperature electrolyser (HTE) 1. Preferably, the electrolyser 1 is of the SOEC (Solid Oxide Electrolysis Cell) type.

[0043] The system comprises several supply and discharge lines connected to the electrolytic cell 1. Thus, by pipeline this is meant a tube, or a set of pipes or tubes, that allow the transport of fluids to and from the electrolytic cell 1.

[0044] The system according to the invention comprises a first supply line 2 of the electrolyser 1, capable of supplying water vapor to the electrolyser 1. According to an option, the first supply line 2 is configured to supply water vapor to the electrolyser 1, by which it is meant that the first supply line 2 can supply a mixture of water vapor and other gases, for example air, or dihydrogen, or carbon dioxide. Upstream of this first supply line 2, water vapor is not yet formed and the first supply line 2 is configured to receive liquid water. According to a preferred option, the first supply line 2 comprises a first part for receiving liquid water and a second part, downstream of the first part, for receiving water vapor. Preferably, the first part is located upstream of a water vapor generator 28 and the second part is located downstream of said water vapor generator 28.

[0045] The system according to the invention comprises a first outlet line 4 capable of discharging dihydrogen (H2) from the electrolyser 1. The first outlet line 4 preferably receives dihydrogen, which is advantageously produced by the electrolyser 1. The dihydrogen is in gaseous form. The first outlet line 4 is capable of discharging a mixture of dihydrogen, called residue, that has not been decomposed by the electrolyser 1, and water vapor.

[0046] The system according to the invention comprises a second discharge line 3 capable of discharging dioxygen (O2) from the electrolyser 1. Preferably, the second discharge line 3 receives dioxygen. The dioxygen is advantageously produced by the electrolyser 1. The dioxygen is in gaseous form. The second discharge line 3 optionally discharges a dioxygen-enriched gas, for example dioxygen-enriched air.

[0047] In the following description, the first supply line 2 will be referred to as the first water vapor supply line 2, the first exhaust line 4 will be referred to as the first dihydrogen exhaust line 4, and the second exhaust line 3 will be referred to as the second dioxygen exhaust line 3, although any fluid or mixture can be transported in these lines, without being limited to gases.

[0048] According to an option, the system comprises a first heat exchange module 5 configured to ensure heat exchange between the first water vapor supply line 2 and the first dihydrogen discharge line 4. This heat exchange module is configured to transfer a quantity of heat from the dihydrogen coming from the electrolyzer 1 to the water intended to supply it. The dihydrogen gas stream ensures a temperature increase of the water stream and also makes it possible to cool the discharged dihydrogen stream, advantageously to be dried or compressed in view of its use.

[0049] The first heat exchange module 5 comprises, according to one embodiment, at least one heat exchanger 5a configured to ensure the heat transfer of dihydrogen to water vapor. According to a preferred embodiment, the first heat exchange module 5 comprises two heat exchangers 5a, 5b arranged in series between the first feed line 2 and the first discharge line 4. This arrangement makes it possible to provide a second heat exchanger 5b adapted to the temperature of the dihydrogen at the outlet of the electrolyzer 1, conventionally around 700°C, and a more conventional first heat exchanger 5a adapted to the temperature of the dihydrogen after its passage through the heat exchanger, conventionally around 330°C. In this way, the components are optimized for the temperature and heat exchange to be achieved.

[0050] According to one embodiment, the system comprises a second supply line 10 capable of supplying air to the electrolyzer 1. Preferably, the second supply line receives air. According to an option, the second supply line 10 is configured to provide air to the electrolyzer 1, meaning that the second supply line 10 is capable of providing air, for example a gas mixture making it possible to scan the cells of the electrolyzer 1 and to remove the dioxygen produced by the electrolyzer 1.

[0051] According to this embodiment, it is advantageous for the system according to the invention to comprise a second heat exchange module 11 configured to ensure heat exchange between the second air supply line 10 and the second dioxygen discharge line 3. This heat exchange module 11 is configured to transfer a quantity of heat from the dioxygen coming from the electrolyzer 1 to the air intended to supply it. The dioxygen gas flow ensures a temperature increase of the air flow and also makes it possible to cool the discharged dioxygen flow.

[0052] The second heat exchange module 11 comprises, according to one embodiment, at least one heat exchanger 11a configured to ensure the heat transfer of dioxygen to air. According to a preferred embodiment, the second heat exchanger module 11 comprises two heat exchangers 11a, 11b arranged in series between the second feed line 10 and the second discharge line 3. This arrangement makes it possible to provide a second heat exchanger 11b adapted to the temperature of the dioxygen at the outlet of the electrolyzer 1, conventionally around 700°C, and a more conventional first heat exchanger 11a adapted to the temperature of the dioxygen after its passage through the heat exchanger, conventionally around 330°C. In this way, the components are optimized for the temperature and heat exchange to be achieved.

[0053] The system preferably comprises a compressor 30 arranged on the second supply line 10 intended to supply air. The compressor 30 is preferably arranged upstream of the second heat exchange module 11, if present. The compressor 30 is intended to ensure the compression of the air intended to be supplied to the electrolyzer 1. The compression of the air advantageously contributes to increasing the temperature of the air before it enters the electrolyzer 1.

[0054] According to an option, the system comprises at least one auxiliary heat source configured to heat the water vapor entering the electrolyser 1 to a predefined target temperature. The auxiliary heat source is advantageously arranged on the first water vapor supply line 2, preferably downstream of the first heat exchange module 5. The auxiliary heat source is, for example, an electric heater 14.

[0055] According to an option, the system comprises at least one auxiliary heat source configured to heat the air entering the electrolyzer 1 to a predefined target temperature. The auxiliary heat source is advantageously arranged on the second air supply line 10, preferably downstream of the second heat exchange module 11. The auxiliary heat source is, for example, an electric heater 13.

[0056] According to an option, the system comprises an electric steam generator 28. The electric steam generator 28 is intended to generate steam from liquid water. The electric steam generator 28 is supplied with energy, in particular electricity, to ensure an increase in the temperature of the liquid water above its evaporation temperature. The electric steam generator 28 is a component that constitutes the main energy consumption of electrolyzer systems according to the prior art. The electric steam generator 28 is arranged on the first steam supply line 2, preferably upstream of the first heat exchange module 5. The electric steam generator 28 is preferably arranged downstream of the first intermediate steam generator 50, in order to ensure the evaporation of the liquid water before it passes to the electric steam generator 28, which limits the electricity consumption. The water at the inlet is advantageously already at least partially in a two-phase state. Conventionally, the water is not in a 100% steam state. The purpose of this steam generator 28 is to generate superheated steam. As an example, the evaporation temperature of the liquid water entering the electric steam generator 28 is about 110° C., or, for example, a reduced pressure steam generator, as shown in FIG. 3, about 70° C.

[0057] According to one embodiment of the invention, the system comprises a module for recovering thermal energy from dihydrogen at the outlet of the heat exchange module 5 for the first water vapor supply line 2 .

[0058] Advantageously, the recovery module is called the first recovery module and comprises a first intermediate exchanger 6 , a first intermediate fluid circuit and a first intermediate steam generator 50 .

[0059] The first intermediate fluid circuit is configured to receive an intermediate fluid and ensures a fluid connection between the first intermediate exchanger 6 and the first intermediate steam generator 50. This intermediate circuit is advantageously a low temperature circuit. By low temperature this means a temperature of the circulating fluid between 25°C and 90°C.

[0060] The first intermediate exchanger 6 is arranged on the first discharge line 2, preferably downstream of the first heat exchange module 5, more specifically downstream of the first heat exchanger 5a of the first heat exchange module 5, and is configured to transfer thermal energy from dihydrogen to the intermediate fluid. The first heat exchanger 6 is fluidly connected to the intermediate fluid circuit by a fluid connection 500 ensuring a fluid connection from the first intermediate exchanger 6 to the first intermediate steam generator 50 and a fluid connection 501 ensuring a fluid connection from the first intermediate steam generator 50 to the first intermediate exchanger 6. By way of example, the intermediate fluid entering the first heat exchanger 6 is at a temperature close to ambient temperature, for example between 18°C ​​and 30°C, and leaves said intermediate exchanger 6 at a temperature of about 70°C. Advantageously, the incoming liquid is in a two-phase state, i.e. one part is in a liquid state and another part is in a gaseous state.

[0061] The first fluid circuit is based on the same principle as the third intermediate circuit 32, in particular as shown in Fig. 2, and as the second intermediate circuit. Preferably, the first intermediate fluid circuit comprises a main branch 510 arranged between the first intermediate steam generator 50 and the fluid connection 500 and configured for the circulation of an intermediate fluid from the first intermediate steam generator 50 to the first intermediate exchanger 6, and a main branch 511 arranged between the fluid connection 501 and the intermediate steam generator 50 and configured for the circulation of an intermediate fluid from the first intermediate exchanger 6 to the first intermediate steam generator 50. By way of example, the intermediate fluid entering the first intermediate steam generator 50 is at a temperature close to the ambient temperature, for example between 18°C ​​and 30°C, and leaves said intermediate steam generator 50 at a temperature of about 110°C for an atmospheric pressure generator and about 70°C if the steam generator operates at reduced pressure, for example as shown in Fig. 3.

[0062] The first intermediate steam generator 50 is configured to transfer thermal energy from the intermediate fluid to the liquid water circulating in the first steam supply line 2. The intermediate steam generator 50 is arranged on the first steam supply line 2, preferably upstream of the first exchanger 5a of the first heat exchange module. According to a first embodiment, the intermediate steam generator 50 is arranged on the first steam supply line 2 upstream of the electric steam generator 28. According to a second embodiment, the intermediate steam generator 50 is arranged on the first steam supply line 2 in parallel with the electric steam generator 28.

[0063] According to one embodiment of the invention, the system comprises a second module for recovering thermal energy from dihydrogen at the outlet of the heat exchange module 5 for the first water vapor supply line 2. According to the invention, the second thermal energy recovery module is a compression type recovery module.

[0064] Advantageously, the reduced pressure recovery module comprises an intermediate exchanger 8, referred to as the third intermediate exchanger 8, an intermediate fluid circuit, referred to as the second intermediate fluid circuit, an intermediate steam generator 60, referred to as the second intermediate generator, a reducer 40 and a compressor 41.

[0065] The reducer 40 and the compressor 41 are arranged on the first water steam supply line 2 and together define a reduced pressure section. The reduced pressure section of the first water steam supply line 2 extends from the outlet of the reducer 40 to the inlet of the compressor 41. The reducer 40 and the compressor 41 are both arranged on the first water steam supply line 2 upstream of the first heat exchange module 5. The reduced pressure section comprises, according to the embodiment shown in Fig. 3, an intermediate water steam generator, a fluid connection K, a condenser 23, a fluid connection L, an electric water steam generator 28 and a fluid connection M.

[0066] The second intermediate fluid circuit is configured to receive an intermediate fluid and ensure a fluid connection between the intermediate exchanger 8 and the intermediate steam generator 60. This intermediate circuit is advantageously a low temperature circuit. By low temperature this means a temperature of the circulating fluid between 25°C and 90°C.

[0067] The third intermediate heat exchanger 8 is arranged on the first dihydrogen discharge line 4 downstream of the first heat exchange module 5, more preferably downstream of the first intermediate heat exchanger 6, preferably upstream of the second intermediate exchanger 7, preferably upstream of the optional air cooler 16 and / or liquid / gas separator 17.

[0068] The vacuum recovery module comprises a second intermediate generator 60 arranged on the first water vapor supply line 2, advantageously on the reduced pressure section. Preferably, the intermediate generator 60 is arranged upstream of the condenser 23, which is advantageously arranged on the reduced pressure section, if one exists.

[0069] The second intermediate steam generator 60 is configured to transfer thermal energy from the intermediate fluid to the liquid water circulating in the first steam supply line 2. The intermediate steam generator 60 is arranged on the first steam supply line 2 on the reduced pressure section, i.e. between the reducer 40 and the compressor 41. The intermediate steam generator 60 is preferably arranged upstream of the electric steam generator 28. The reduced pressure recovery module thus proposes to reduce the pressure in a part of the first steam supply line 2 in order to reduce the boiling point of the water circulating in the first supply line 2. The reduced pressure is then preferably compensated by recompression up to atmospheric pressure. The reduced pressure section surrounds at least the second intermediate steam generator 60, and preferably also the compressor 23 and / or the electric generator 28.

[0070] Preferably, the boiling of the water is carried out at a temperature lower than the temperature of the thermal exhaust of the electrolyser 1, in particular the temperature of the dioxygen and dihydrogen, which is favorable for the exchange and therefore for carrying out the thermal exhaust.

[0071] According to one embodiment, the system comprises at least one pump arranged on the first water vapor supply line 2 and configured to move liquid water in the first supply line 2 .

[0072] The third heat exchanger 8 is fluidly connected to the second intermediate fluid circuit by a fluid connection 600 that ensures a fluid connection from the third intermediate exchanger 8 to the second intermediate steam generator 60 and a fluid connection 601 that ensures a fluid connection from the second intermediate steam generator 60 to the intermediate exchanger 8.

[0073] Preferably, the intermediate fluid circuit comprises a main branch 610 arranged between the second intermediate steam generator 60 and the fluid connection 600 and configured for the circulation of an intermediate fluid from the intermediate steam generator 60 to the third intermediate exchanger 8, and a main branch 611 arranged between the fluid connection 601 and the intermediate steam generator 60 and configured for the circulation of an intermediate fluid from the intermediate exchanger 8 to the intermediate steam generator 60. By way of example, the intermediate fluid entering the intermediate steam generator 60 has a temperature of about 90°C and leaves said intermediate steam generator 60 at a temperature of about 35°C.

[0074] According to one embodiment of the invention, the system comprises a third module for recovering thermal energy from dihydrogen at the outlet of the heat exchanger 5 for the first water vapor supply line 2 .

[0075] According to an option, the recovery module comprises a heat pump and an intermediate circuit.

[0076] Advantageously, the intermediate circuit comprises a third intermediate fluid circuit 32 configured to receive an intermediate fluid and a second intermediate exchanger 7 arranged on the first discharge line 2, preferably downstream of the first heat exchange module 5, more particularly downstream of the first heat exchanger 5a of the first heat exchange module 5, and configured to transfer thermal energy from the dihydrogen to the intermediate fluid, preferably downstream of the first intermediate heat exchanger 6. The third intermediate fluid circuit 32 makes it possible to ensure a fluid connection between the second intermediate exchanger 7 and the heat pump. This third intermediate exchanger 32 is advantageously a low temperature circuit. By low temperature this means a temperature of the circulating fluid between 25 ° C and 90 ° C.

[0077] The second heat exchanger 7 is fluidly connected to the third intermediate fluid circuit 32 by a fluid connection 400 ensuring a fluid connection from the second intermediate exchanger 7 to the evaporator 25 and a fluid connection 401 ensuring a fluid connection from the evaporator 25 to the second intermediate exchanger 7. By way of example, the intermediate fluid entering the second heat exchanger 7 has a temperature of approximately 25° C. and leaves said second heat exchanger 7 at a temperature of approximately 70° C. By way of example, these temperatures are valid for the different heat exchangers arranged in the first and second intermediate circuits.

[0078] Preferably, the third intermediate fluid circuit 32 comprises a main branch 410 arranged between the evaporator 25 and the fluid connection 401 and configured for the circulation of an intermediate fluid from the evaporator 25 to the intermediate exchanger, and a main branch 411 arranged between the fluid connection 400 and the evaporator 25 and configured for the circulation of an intermediate fluid from the intermediate exchanger to the evaporator 25. By way of example, the intermediate fluid entering the evaporator 25 has a temperature of about 90°C and leaves said evaporator 25 at a temperature of about 35°C.

[0079] The heat pump is configured to transfer thermal energy from the intermediate fluid to liquid water circulating in the first water vapour supply line 2 .

[0080] The heat pump comprises a condenser 23, a reducer 24, at least one evaporator 25, and a compressor 26. The heat pump comprises a fluid circuit 27 capable of receiving a heat transfer fluid.

[0081] The heat transfer fluid is a fluid conventionally used in heat pumps, such as, for example, 1234yf: 2,3,3,3-tetrafluoropropene (HFO-1234yf), or R245FA pentafluoropropane, or R290 propane.

[0082] The fluid circuit 27 ensures the fluid connection of the components of the heat pump, preferably in a closed circuit.

[0083] According to one embodiment, the fluid circuit 27 comprises a fluid connection 200 connected between the outlet of the compressor 26 and the inlet of the condenser 23. Advantageously, the fluid circuit 27 comprises a fluid connection 201 connected between the outlet of the condenser 23 and the inlet of the reducer 24. Advantageously, the fluid circuit 27 comprises a fluid connection 202 connected between the outlet of the reducer 24 and the inlet of the evaporator 25. Advantageously, the fluid circuit 27 comprises a fluid connection 203 connected between the outlet of the evaporator 25 and the inlet of the compressor 26.

[0084] According to the invention, the condenser 23 of the heat pump is arranged on the first steam supply line 2, preferably upstream of the first intermediate steam generator 50 or upstream of the outlet fluid connection of the first intermediate steam generator 50. This arrangement allows to transfer the amount of heat from the heat transfer fluid for liquid water circulating in the first supply line 2 upstream of the first intermediate steam generator 50, preferably upstream of the electric steam generator 28. In one example, the water entering the condenser 23 is at a temperature close to the ambient temperature in an embodiment at atmospheric pressure, as shown for example in FIG. 1, and leaves said condenser 23 at a temperature of about 110° C., or the water entering the condenser 23 is advantageously at a temperature of about 70° C. and leaves said condenser 23 at a temperature of about 75° C., in two-phase state in an embodiment of reduced pressure type, as shown for example in FIG. 3.

[0085] The invention makes it possible to utilize the waste heat from the system, and more specifically the thermal exhaust of the dihydrogen produced. The heat pump is an active system that makes it possible to reinject the recovered heat into the dihydrogen produced, at a temperature higher than the evaporation temperature of water, upstream of the first intermediate steam generator 6, preferably upstream of the electric steam generator 28.

[0086] According to one embodiment, the first recovery module of the system comprises a fourth intermediate heat exchanger 9 arranged on the first water vapor supply line 2 and on the second dioxygen discharge line 3. The fourth intermediate heat exchanger 9 is preferably arranged on the second discharge line 3. This fourth intermediate heat exchanger 9 is configured for the first water vapor supply line 2 to ensure the heat transfer via the first intermediate fluid circuit and the first intermediate water vapor generator 50 of the amount of heat collected in the dioxygen stream discharged from the electrolyzer 1 and circulating in the second discharge line 3.

[0087] The fourth heat exchanger 9 is fluidly connected to the intermediate fluid circuit by a fluid connection 503 ensuring a fluid connection from the fourth intermediate exchanger 9 to the first steam generator 50 and a fluid connection 502 ensuring a fluid connection from the first steam generator 50 to the fourth intermediate exchanger 9.

[0088] Preferably, the fluid connection 503 is fluidly connected to a main branch 511 configured for the circulation of an intermediate fluid from the intermediate exchanger 9 to the first steam generator 50. Preferably, the fluid connection 502 is fluidly connected to a main branch 510 configured for the circulation of an intermediate fluid to the intermediate exchanger 9.

[0089] The fourth intermediate exchanger 9 is advantageously arranged in parallel with the first intermediate exchanger 6 .

[0090] According to a preferred embodiment, the third recovery module, and more particularly the intermediate circuit, comprises a seventh intermediate exchanger 29 arranged on the second dihydrogen discharge line 3. The seventh intermediate exchanger 29 is a heat exchanger configured to ensure the transfer of a quantity of heat from the dihydrogen discharged from the electrolyzer 1 to an intermediate fluid, with a view to being used in the heat pump of the third recovery module.

[0091] The seventh heat exchanger 29 is fluidly connected to the intermediate fluid circuit 32 by a fluid connection 406 that ensures a fluid connection from the seventh intermediate exchanger 29 to the evaporator 25 and a fluid connection 407 that ensures a fluid connection from the evaporator 25 to the seventh intermediate exchanger 29.

[0092] Preferably, the fluid connection 406 is fluidly connected to a main branch 411 configured for the circulation of the intermediate fluid 29 from the intermediate exchanger to the evaporator 25. Preferably, the fluid connection 407 is fluidly connected to a main branch 410 configured for the circulation of the intermediate fluid 29 to the intermediate exchanger.

[0093] According to one embodiment, the second system recovery module comprises a twelfth intermediate heat exchanger 39 arranged on the second dioxygen discharge line 3 and on the second intermediate circuit, which is configured to ensure the heat transfer, via the second intermediate fluid circuit and the second intermediate steam generator 60, of the amount of heat collected in the dioxygen stream leaving the electrolyzer 1 and circulating in the second discharge line 3 for the first steam supply line 2.

[0094] The twelfth heat exchanger 39 is fluidly connected to the intermediate fluid circuit by a fluid connection 603 that ensures a fluid connection from the twelfth intermediate exchanger 39 to the second steam generator 60 and a fluid connection 602 that ensures a fluid connection from the second steam generator 60 to the twelfth intermediate exchanger 39.

[0095] Preferably, the fluid connection 603 is fluidly connected to main branch 1 configured for the circulation of an intermediate fluid from the intermediate exchanger 39 to the second steam generator 60. Preferably, the fluid connection 602 is fluidly connected to main branch 0 configured for the circulation of an intermediate fluid to the intermediate exchanger 39.

[0096] The twelfth intermediate exchanger 39 is advantageously arranged in parallel with the third intermediate exchanger 8 .

[0097] According to one embodiment, the system comprises means for treating the dihydrogen stream produced. The dihydrogen produced by the electrolyzer 1 and emerging therefrom through the first discharge line 4 first has a very high temperature corresponding to the reaction temperature of the electrolyzer 1. However, in view of its use, the dihydrogen must preferably be returned to a temperature close to the ambient temperature. Furthermore, the dihydrogen discharged from the electrolyzer 1 through the first discharge line 4 may contain water vapor that is removed together with the dihydrogen stream. It is therefore also preferable to separate the dihydrogen from the water vapor that may be removed together with the dihydrogen stream by drying the dihydrogen.

[0098] The system according to the invention advantageously comprises, for this purpose, a first treatment stage intended for drying and / or compressing the dihydrogen produced.

[0099] Advantageously, the first treatment stage is arranged downstream of the second intermediate exchanger 7 of the third recovery module.

[0100] According to an option, the first treatment stage comprises a heat exchanger, which is arranged on the first discharge line 4, preferably downstream of the intermediate exchanger 7. This heat exchanger is, according to a first option, an air cooler 16, i.e. a heat exchanger between a fluid and a gas, the latter being moved through a fan. According to another option, the heat exchanger is a standard cooler, i.e. without a fan, but this solution is less effective. According to an option not shown in the figure, the heat exchanger ensures the heat exchange between a fluid and a gas, in particular air, intended to feed the electrolyzer 1.

[0101] The first treatment stage advantageously comprises a liquid / gas separator 17 arranged downstream of the air cooler 16. The separator 17 makes it possible to separate the liquid water from the gaseous dihydrogen, the liquid water resulting from cooling the water vapor in the air cooler 16 below its condensation point.

[0102] According to a preferred option, the system comprises a second treatment stage arranged downstream of the first treatment stage on the first discharge line 4. The second treatment stage makes it possible to complete the drying of the dihydrogen. The second treatment stage advantageously comprises a heat exchanger, which, like the first stage, can be a standard cooler, an air cooler 19 or a third heat exchanger between the fluid (dihydrogen) and the air intended to feed the electrolyzer 1. The second stage comprises a liquid / gas separator 20. Preferably, the system comprises, between the first and second treatment stages, a compressor 18 configured to allow a second treatment by the air cooler 19 by pre-raising the temperature of the mixture so that the mixture can be cooled again.

[0103] If present, liquid water coming from the first and / or second treatment stages is preferably recycled by being returned to the first water steam supply line 2 through a water recycle line 21. The water recycle line is preferably fluidly connected to the first supply line 2 upstream of the first intermediate generator 50. The dihydrogen may be used as such, in particular stored after conventional processing.

[0104] The system preferably comprises a pump on the water recycle line 21. The pump is configured to circulate in the water recycle line 21 and in particular to move the liquid water coming from the gas / liquid separators 17, 20.

[0105] According to a preferred embodiment of the invention, the third recovery module is more particularly an intermediate circuit comprising intermediate exchangers arranged in the treatment stages, preferably in each treatment stage.

[0106] The intermediate circuit of the third recovery module advantageously comprises an intermediate exchanger 12, called, without being limited thereto or in accordance with the need to have another intermediate exchanger, the fifth intermediate exchanger 12. The fifth intermediate exchanger 12 is preferably arranged downstream of the compressor 18 and preferably upstream of the air cooler 19.

[0107] The intermediate circuit of the third recovery module advantageously comprises an intermediate exchanger 15, called, without being limited thereto or in accordance with the need to have another intermediate exchanger, the sixth intermediate exchanger 15. The sixth intermediate exchanger 15 is preferably arranged downstream of the compressor 22 and preferably upstream of the air cooler 31.

[0108] If the system includes another type of treatment downstream of the second treatment stage, the third recovery module may comprise an nth intermediate exchanger in this other treatment stage, advantageously located downstream of the compressor and upstream of the air cooler.

[0109] According to an embodiment of the invention, the intermediate exchangers of the intermediate circuit are arranged in parallel with one another on the intermediate fluid circuit, as shown in Figure 2. This arrangement greatly facilitates modularity of the system and of the number of intermediate exchangers used.

[0110] The fifth intermediate exchanger 12 is fluidly connected to the main branch 410 by fluid connection 403 and to the main branch 411 by fluid connection 402 .

[0111] The sixth intermediate exchanger 15 is fluidly connected to the main branch 410 by a fluid connection 405 and to the main branch 411 by a fluid connection 404 .

[0112] According to an option not shown, the system comprises an intermediate exchanger arranged on a source of cold outside the system, for example a heat rejection source.

[0113] According to a preferred embodiment of the invention, the first recovery module, and more particularly the intermediate fluid circuit, comprises an intermediate exchanger arranged in the treatment stages, preferably in each treatment stage.

[0114] The first recovery module advantageously comprises an intermediate exchanger 35, called, without being limited thereto or in accordance with the need to have another intermediate exchanger, the eighth intermediate exchanger 35. The eighth intermediate exchanger 35 is preferably arranged downstream of the compressor 18 and preferably upstream of the air cooler 19.

[0115] The first recovery module advantageously comprises an intermediate exchanger 37, called, without being limited thereto or in accordance with the need to have another intermediate exchanger, tenth intermediate exchanger 37. The tenth intermediate exchanger 37 is preferably arranged downstream of the compressor 22 and preferably upstream of the air cooler 31.

[0116] If the system includes a further treatment stage downstream of the second treatment stage, the third recovery module may comprise an nth intermediate exchanger in this further treatment stage, advantageously arranged downstream of the compressor and upstream of the air cooler.

[0117] According to an embodiment of the invention, the intermediate exchangers of the intermediate circuit are arranged in parallel with one another on the intermediate fluid circuit, as shown in Figure 2 for fluid circuit 32. This arrangement greatly facilitates modularity of the system and of the number of intermediate exchangers used.

[0118] The eighth intermediate exchanger 35 is fluidly connected to main branch 510 by fluid connection 504 and to main branch 511 by fluid connection 505 .

[0119] The tenth intermediate exchanger 37 is fluidly connected to main branch 510 by fluid connection 506 and to main branch 511 by fluid connection 507 .

[0120] According to a preferred embodiment of the invention, the second recovery module, and more particularly the intermediate fluid circuit, comprises an intermediate exchanger arranged in the treatment stages, preferably in each treatment stage.

[0121] The second recovery module advantageously comprises an intermediate exchanger 36, called, without being limited thereto or in accordance with the need to have another intermediate exchanger, the ninth intermediate exchanger 36. The ninth intermediate exchanger 36 is preferably arranged downstream of the compressor 18 and preferably upstream of the air cooler 19.

[0122] The second recovery module advantageously comprises an intermediate exchanger 38, called, without being limited thereto or in accordance with the need to have another intermediate exchanger, the eleventh intermediate exchanger 38. The eleventh intermediate exchanger 38 is preferably arranged downstream of the compressor 22 and preferably upstream of the air cooler 31.

[0123] If the system includes a further treatment stage downstream of the second treatment stage, the third recovery module may comprise an nth intermediate exchanger in this further treatment stage, advantageously arranged downstream of the compressor and upstream of the air cooler.

[0124] According to an embodiment of the invention, the intermediate exchangers of the intermediate circuit are arranged in parallel with one another on the intermediate fluid circuit, as shown in Figure 2 for fluid circuit 32. This arrangement greatly facilitates modularity of the system and of the number of intermediate exchangers used.

[0125] The ninth intermediate exchanger 36 is fluidly connected to main branch 610 by fluid connection 604 and to main branch 611 by fluid connection 605 .

[0126] The eleventh intermediate exchanger 38 is fluidly connected to main branch 610 by fluid connection 606 and to main branch 611 by fluid connection 607 .

[0127] The electrolyser 1 receives water vapour, advantageously air, and outputs dihydrogen and dioxygen.

[0128] Fluid connections are preferably direct and, with the option of additional components, can be integrated by considering the relative positioning of the components described below.

[0129] Preferably, the electrolytic cell 1 is fluidly connected to a first water vapor supply line 2. The first water vapor supply line 2 ensures the fluid connection of the components arranged upstream of the electrolytic cell 1 on said supply line 2. The following description is made by starting from upstream of the electrolytic cell 1 and following the direction of circulation of water and / or water vapor in the first supply line 2.

[0130] According to the embodiment shown in FIG. 1 , the first supply line 2 ensures a fluid connection to the inlet of the condenser 23, then from the outlet of the condenser 23 to the inlet of the first intermediate steam generator 50, then from the outlet of the first intermediate steam generator 50 to the inlet of the electric steam generator 28, then from the outlet of the electric steam generator 28 to the inlet of the first heat exchange module 5, preferably the first heat exchanger 5a, then from the outlet of the first heat exchanger 5a to the inlet of the second heat exchanger 5b, then from the outlet of the second heat exchanger 5b to the inlet of the electric heater 14, then from the outlet of the electric heater 14 to the inlet of the electrolyzer 1.

[0131] According to the embodiment shown in Fig. 2, the water inlet feeds two parallel branches. The first branch, corresponding to the reduced pressure section, advantageously comprises a fluid connection J ensuring the inlet of liquid water in the reducer 40, then a fluid connection from the outlet of the reducer 40 to the inlet of the low-pressure second intermediate steam generator 60, then a fluid connection from the outlet of the second intermediate steam generator 60 advantageously to the inlet of the condenser 23, if present, then a fluid connection from the outlet of the condenser 23 to the inlet of the electric steam generator 28, then a fluid connection from the outlet of the electric steam generator 28 to the inlet of the compressor 41. The second branch, corresponding to the atmospheric pressure supply line, advantageously comprises a fluid connection O ensuring the inlet of liquid water in the first intermediate generator 50, then a fluid connection P ensuring the outlet of steam from the second intermediate generator 50, advantageously with the outlet fluid connection N of the compressor 41 opening into the inlet of the heat exchange module 5.

[0132] Preferably, the electrolyzer 1 is fluidly connected with a first dihydrogen discharge line 4. The first discharge line 4 ensures the fluid connection of the components arranged downstream of the electrolyzer 1 on said first discharge line 4. The following description is made by starting from the electrolyzer 1 and following the direction of circulation in the first discharge line 4 from the electrolyzer 1.

[0133] According to the embodiment shown in FIG. 1 , the first discharge line 4 ensures a fluid connection between the electrolyzer 1 and the inlet of the first heat exchange module 5, more specifically the second heat exchanger 5b, then from the second heat exchanger 5b to the first heat exchanger 5a, then from the first heat exchanger 5a to the inlet of the first intermediate heat exchanger 6, then from the outlet of the first intermediate heat exchanger 6 to the inlet of the second intermediate exchanger 7, then from the outlet of the second intermediate exchanger 7 to the inlet of the air cooler 16, then from the inlet of the air cooler to the inlet of the liquid / gas separator 17, then from the outlet of the liquid / gas separator 17 to the inlet of the compressor 18. 1. Then, advantageously, a fluid connection is ensured from the outlet of the compressor 18 to the inlet of the fifth intermediate exchanger 12, then a fluid connection is ensured from the fifth intermediate exchanger 12 to the air cooler 19, then a fluid connection is ensured from the air cooler 19 to the liquid / gas separator 20, advantageously, a fluid connection is ensured from the outlet of the liquid / gas separator 20 to the inlet of the compressor 22, then a fluid connection is ensured from the outlet of the compressor to the inlet of the sixth heat exchanger 15, then a fluid connection is ensured from the outlet of the sixth heat exchanger 15 to the inlet of the air cooler 31, then a fluid connection is ensured from the outlet of the air cooler 31 to the separator 34, then a fluid connection is ensured from the outlet of the separator 34 directly or indirectly to the dihydrogen storage.

[0134] According to the embodiment shown in FIG. 2, the first discharge line 4 ensures a fluid connection between the electrolyzer 1 and the inlet of the first heat exchange module 5, more specifically the second heat exchanger 5b, then from the second heat exchanger 5b to the first heat exchanger 5a, then from the first heat exchanger 5a to the inlet of the first intermediate heat exchanger 6, then from the outlet of the first intermediate heat exchanger 6 to the inlet of the third intermediate exchanger 8, then from the outlet of the third intermediate heat exchanger 8 to the inlet of the third intermediate heat exchanger 8. a fluid connection is then ensured from the outlet of the first intermediate exchanger 8 to the inlet of the second intermediate exchanger 7, then from the outlet of the second intermediate exchanger 7 to the inlet of the air cooler 16, then from the inlet of the air cooler to the inlet of the liquid / gas separator 17, then from the outlet of the liquid / gas separator 17 to the inlet of the compressor 18, then advantageously from the outlet of the compressor 18 to the inlet of the eighth intermediate exchanger 35, then , a fluid connection is ensured from the outlet of the eighth intermediate exchanger 35 to the inlet of the ninth intermediate exchanger 36, then from the outlet of the ninth intermediate exchanger 36 to the inlet of the fifth intermediate exchanger 12, then from the fifth intermediate exchanger 12 to the air cooler 19, then from the air cooler 19 to the liquid / gas separator 20, advantageously from the outlet of the compressor to the inlet of the tenth intermediate exchanger 37, then from the tenth intermediate exchanger 38 to the inlet of the tenth intermediate exchanger 39. A fluid connection is then ensured from the outlet of the first intermediate exchanger 37 to the inlet of the eleventh intermediate exchanger 38, then a fluid connection is ensured from the outlet of the eleventh intermediate exchanger 38 to the inlet of the sixth heat exchanger 15, then a fluid connection is ensured from the outlet of the sixth heat exchanger 15 to the inlet of the air cooler 31, then a fluid connection is ensured from the outlet of the air cooler 31 to the inlet of the separator 34, then a fluid connection is ensured from the outlet of the separator 34 directly or indirectly to the dihydrogen storage section.

[0135] Preferably, the electrolytic cell 1 is fluidly connected to a second dioxygen discharge line 3. The second discharge line 3 ensures the fluid connection of the components arranged downstream of the electrolytic cell 1 on said second discharge line 3. The following description is made by starting from the electrolytic cell 1 and following the direction of circulation in the second discharge line 3 from the electrolytic cell 1. The second discharge line 3 ensures a fluid connection between the electrolyzer 1 and the second heat exchange module 11, more preferably the second heat exchanger 11b, then from the second heat exchanger 11b to the first heat exchanger 11a, then from the first heat exchanger 11a to the inlet of the fourth intermediate exchanger 9, to the inlet of the seventh intermediate exchanger 29, then from the outlet of the seventh intermediate exchanger 29 according to the embodiment shown in FIG. 1 or the embodiment shown in FIG. 2, from the outlet of the fourth intermediate exchanger 9 to the inlet of the twelfth intermediate exchanger 39, then from the outlet of the second intermediate exchanger 39 to the inlet of the seventh intermediate exchanger 29, then from the outlet of the seventh intermediate exchanger 29.

[0136] Preferably, the electrolyzer 1 is fluidly connected to a second air supply line 10. The second supply line 10 ensures the fluid connection of the components arranged upstream of the electrolyzer 1 on said second supply line 10. The second supply line 10 ensures the fluid connection from the compressor 12 to the first heat exchanger 11a, then from the first heat exchanger 11a to the second heat exchanger 11b, then from the second heat exchanger 11b to the electric heater 13, then from the electric heater 13 to the electrolyzer 1. According to an option not shown, upstream of the compressor 30, the second supply line ensures the fluid connection from a heat exchanger instead of the air cooler 16 and / or 19 to the compressor 30.

[0137] The intermediate circuit as shown in Figure 2 comprises an intermediate fluid circuit 32 ensuring the fluid connection of the intermediate exchangers 7, 12, 15, 29 and the heat pump, more particularly the evaporator 28. According to an embodiment, there are several intermediate exchangers 7, 12, 15, 29, which are arranged in parallel with one another. The intermediate fluid circuit 32 advantageously comprises a pump 33 intended to circulate an intermediate fluid within the intermediate fluid circuit 32.

[0138] The system advantageously comprises the fluid connections described below.

[0139] 1, it advantageously comprises a fluid connection A connected to the inlet of the condenser 23. The fluid connection A makes it possible to introduce water into the condenser 23, in particular from the recycled water circulating in the recycled line 21.

[0140] Advantageously, the first supply line 2 comprises a fluid connection B connected between the outlet of the condenser 23 and the inlet of the first intermediate steam generator 50 .

[0141] Advantageously, the first supply line 2 comprises a fluid connection C connected between the outlet of the first intermediate water steam generator 50 and the inlet of the electric water steam generator 28 .

[0142] Advantageously, the first supply line 2 comprises a fluid connection D connected between the outlet of the electric water vapor generator 28 and the inlet of the first heat exchanger 5 a of the heat exchange module 5 .

[0143] Advantageously, the first supply line 2 comprises a fluid connection E connected between the outlet of the first heat exchanger 5a of the heat exchange module 5 and the inlet of the first heat exchanger 5a of the heat exchange module 5, allowing the recirculation of the water coming from the 10 hours of electrolysis to be removed together with the hydrogen fluid.

[0144] Advantageously, the first supply line 2 comprises a fluid connection F connected between the outlet of the first heat exchanger 5a and the inlet of the second heat exchanger 5b.

[0145] Advantageously, the first supply line 2 comprises a fluid connection G connected between the outlet of the second heat exchanger 5b and the inlet of the heater 14.

[0146] Advantageously, the first supply line 2 comprises a fluid connection H connected between the outlet of the electric heater 14 and the inlet of the electrolytic cell 1 .

[0147] Regarding the first supply line 2, according to the embodiment shown in Fig. 1, it advantageously comprises a fluid connection I providing water to the supply line 2. The fluid connection I makes it possible to supply water to two parallel branches, the reduced pressure part and that branch comprising a first intermediate water steam generator 50.

[0148] Advantageously, the first supply line 2 comprises a fluid connection I ensuring a fluid connection J between it and the inlet of the second intermediate steam generator 60. The fluid connection J comprises the reducer 40.

[0149] Advantageously, the first supply line 2 comprises a fluid connection K ensuring a fluid connection between the outlet of the second water vapour generator 60 and the inlet of the condenser 23 .

[0150] Advantageously, the first supply line 2 comprises a fluid connection L ensuring the connection between the outlet of the condenser 23 and the inlet of the electric generator 28 .

[0151] Advantageously, the first supply line 2 comprises a fluid connection M ensuring a fluid connection between the outlet of the electric generator 28 and the inlet of the compressor 41 .

[0152] Advantageously, the first supply line 2 comprises a fluid connection N ensuring a fluid connection between the outlet of the compressor 22 and the inlet of the first heat exchanger 5a.

[0153] Advantageously, the first supply line 2 comprises a fluid connection O ensuring a fluid connection between the fluid connection I and the inlet of the first intermediate water steam generator 50 .

[0154] Advantageously, the first supply line 2 comprises a fluid connection P ensuring a fluid connection between the outlet of the first intermediate water steam generator 50 and a fluid connection N.

[0155] Advantageously, the first supply line 2 comprises a fluid connection F connected between the outlet of the first heat exchanger 5a and the input of the second heat exchanger 5b.

[0156] Advantageously, the first supply line 2 comprises a fluid connection G connected between the outlet of the second heat exchanger 5b and the inlet of the heater 14.

[0157] Advantageously, the first supply line 2 comprises a fluid connection H connected between the outlet of the electric heater 14 and the inlet of the electrolytic cell 1 .

[0158] Regarding the first discharge line 4 , it advantageously comprises a first fluid connection 300 between the outlet of the electrolyzer 1 and the inlet of the second heat exchanger 5 b of the first heat exchange module 5 .

[0159] Advantageously, the first discharge line 4 comprises a fluid connection 301 between the outlet of the second heat exchanger 5 b of the first heat exchange module 5 and the inlet of the first heat exchanger 5 a of the first heat exchange module 5 .

[0160] Advantageously, the first discharge line 4 comprises a fluid connection 302 between the outlet of the first heat exchanger 5 a and the inlet of the water steam generator 6 .

[0161] According to the embodiment shown in FIG. Advantageously, the first discharge line 4 comprises a fluid connection 303 between the outlet of the water vapor generator 6 and the inlet in the second intermediate exchanger 7 .

[0162] Advantageously, the first discharge line 4 comprises a fluid connection 304 between the outlet of the second intermediate exchanger 7 and the inlet of the first air cooler 16 .

[0163] Advantageously, the first discharge line 4 comprises a fluid connection 305 between the outlet of the first air cooler 16 and the inlet of the separator 17 .

[0164] Advantageously, the first discharge line 4 comprises a fluid connection 306 between the outlet of the separator 17 and the inlet of the compressor 18 .

[0165] Advantageously, the first discharge line 4 comprises a fluid connection 307 between the outlet of the compressor 18 and the inlet of the second intermediate exchanger 12 .

[0166] Advantageously, the first discharge line 4 comprises a fluid connection 308 between the outlet of the second intermediate exchanger 12 and the inlet of the air cooler 19 .

[0167] Advantageously, the first discharge line 4 comprises a fluid connection 309 between the outlet of the air cooler 19 and the inlet of the separator 20 .

[0168] Advantageously, the first discharge line 4 comprises a fluid connection 310 between the outlet of the separator 20 and the inlet of the compressor 30 .

[0169] Advantageously, the first discharge line 4 comprises a fluid connection 311 between the outlet of the compressor 30 and the inlet of the sixth intermediate exchanger 15 .

[0170] Advantageously, the first discharge line 4 comprises a fluid connection 312 between the outlet of the sixth intermediate exchanger 15 and the inlet of the air cooler 31 .

[0171] Advantageously, the first discharge line 4 comprises a fluid connection 313 between the outlet of the air cooler 31 and the inlet of the separator 34 .

[0172] Advantageously, the first discharge line 4 comprises a fluid connection 314 ensuring the exit of dihydrogen from the separator 34 .

[0173] According to the embodiment shown in FIG. Advantageously, the first discharge line 4 comprises a fluid connection 315 between the outlet of the first intermediate exchanger 6 and the inlet of the third intermediate exchanger 8 .

[0174] Advantageously, the first discharge line 4 comprises a fluid connection 316 between the outlet of the third intermediate exchanger 8 and the inlet of the second intermediate exchanger 7 .

[0175] Advantageously, the first discharge line 4 comprises a fluid connection 304 between the outlet of the second intermediate exchanger 7 and the inlet of the first air cooler 16 .

[0176] Advantageously, the first discharge line 4 comprises a fluid connection 305 between the outlet of the first air cooler 16 and the inlet of the separator 17 .

[0177] Advantageously, the first discharge line 4 comprises a fluid connection 306 between the outlet of the separator 17 and the inlet of the compressor 18 .

[0178] Advantageously, the first discharge line 4 comprises a fluid connection 317 between the outlet of the compressor 18 and the inlet of the eighth intermediate exchanger 35 .

[0179] Advantageously, the first discharge line 4 comprises a fluid connection 318 between the output of the eighth intermediate exchanger 35 and the inlet of the ninth intermediate exchanger 36 .

[0180] Advantageously, the first discharge line 4 comprises a fluid connection 319 between the outlet of the ninth intermediate exchanger 36 and the inlet of the fifth intermediate exchanger 12 .

[0181] Advantageously, the first discharge line 4 comprises a fluid connection 308 between the outlet of the second intermediate exchanger 12 and the inlet of the air cooler 19 .

[0182] Advantageously, the first discharge line 4 comprises a fluid connection 309 between the outlet of the air cooler 19 and the inlet of the separator 20 .

[0183] Advantageously, the first discharge line 4 comprises a fluid connection 310 between the outlet of the separator 20 and the inlet of the compressor 30 .

[0184] Advantageously, the first discharge line 4 comprises a fluid connection 320 between the outlet of the compressor 22 and the inlet of the tenth intermediate exchanger 37 .

[0185] Advantageously, the first discharge line 4 comprises a fluid connection 321 between the outlet of the tenth intermediate exchanger 37 and the inlet of the eleventh intermediate exchanger 38 .

[0186] Advantageously, the first discharge line 4 comprises a fluid connection 322 between the outlet of the eleventh intermediate exchanger 38 and the inlet of the sixth intermediate exchanger 15 .

[0187] Advantageously, the first discharge line 4 comprises a fluid connection 312 between the outlet of the sixth intermediate exchanger 15 and the inlet of the air cooler 31 .

[0188] Advantageously, the first discharge line 4 comprises a fluid connection 313 between the outlet of the air cooler 31 and the inlet of the separator 34 .

[0189] Advantageously, the first discharge line 4 comprises a fluid connection 314 ensuring the exit of dihydrogen from the separator 34 .

[0190] As regards the second dioxygen discharge line 3 , it is advantageously provided with a fluid connection 100 between the outlet of the electrolyser 1 and the inlet of the twenty-second heat exchanger 11 b of the second heat exchange module 11 .

[0191] Advantageously, the second discharge line 3 comprises a fluid connection 101 between the outlet of the second heat exchanger 11 b and the inlet of the first heat exchanger 11 a of the second heat exchange module 11 .

[0192] Advantageously, the second discharge line 3 comprises a fluid connection 102 between the outlet of the first heat exchanger 11 a and the inlet of the heat exchanger 9 .

[0193] According to the embodiment shown in Figure 1, the second discharge line 3 advantageously comprises a fluid connection 103 between the outlet of the heat exchanger 9 and the inlet of the seventh intermediate exchanger 29. Advantageously, the second discharge line 3 comprises a fluid connection 104 between the output of the seventh intermediate exchanger 29 and the outside.

[0194] According to the embodiment shown in Fig. 2, advantageously, the second discharge line 3 comprises a fluid connection 105 between the outlet of the heat exchanger 9 and the inlet of the twelfth intermediate exchanger 39. Advantageously, the second discharge line 3 comprises a fluid connection 106 between the outlet of the twelfth intermediate exchanger 39 and the inlet of the seventh intermediate exchanger 29. Advantageously, the second discharge line 3 comprises a fluid connection 104 between the outlet of the seventh intermediate exchanger 29 and the outside.

[0195] Regarding the second air supply line 4 , according to an option not shown, a fluid connection 110 is provided between the outlet of a heat exchanger replacing the air cooler 16 and the inlet of the compressor 30 .

[0196] Advantageously, the second supply line 4 comprises a fluid connection 111 between the outlet of the compressor 30 and the inlet of the first heat exchanger 11 a of the second heat exchange module 11 .

[0197] Advantageously, the second supply line 4 comprises a fluid connection 112 between the outlet of the first heat exchanger 11 a and the inlet of the second heat exchanger 11 b of the second heat exchange module 11 .

[0198] Advantageously, the second supply line 4 comprises a fluid connection 113 between the outlet of the second heat exchanger 11 b and the inlet of the electric heater 13 .

[0199] Advantageously, the first supply line 4 comprises a fluid connection 114 between the outlet of the electric heater 13 and the inlet of the electrolytic cell 1 .

[0200] In operation, according to the first embodiment shown in FIG. 1, liquid water arrives in the first water vapor supply line 2, more specifically in the first part, by fluid connection A. Fluid communication A is advantageously connected to the inlet of the condenser 23. The liquid water enters the condenser 23. The temperature of the water is increased by the transfer of heat from the heat transfer fluid of the heat pump, due to the liquid water. In the condenser 23, the heat transfer fluid transfers its heat to the water, which ensures the condensation of the heat transfer fluid in the condenser 23. The heated liquid water leaves the condenser 23 by fluid connection B, advantageously at a temperature close to the evaporation temperature, i.e. ±5° C., and enters preferably directly into the first intermediate water vapor generator 50. The liquid water is converted into water vapor by the intermediate water vapor generator 50, which recovers the thermal energy coming from the dihydrogen produced by the electrolyzer 1, at least via the first intermediate exchanger 6. According to the energy transferred to the first intermediate exchanger 50, water emerges therefrom and preferably enters directly, via a fluid connection C, into the electric steam generator 28.

[0201] The liquid water introduced via connection A can be water from the water network, or recycled water coming from the separator of the system, or a mixture of the two.

[0202] According to the invention, the energy that needs to be supplied by the electric steam generator 28 for converting liquid water into steam is reduced thanks to the first thermal energy recovery module, advantageously the third thermal energy recovery module, in particular the condenser 23 of the heat pump.

[0203] Steam leaves the electric steam generator 28 through the fluid connection D and enters, preferably directly, into the first heat exchanger 5, preferably the first heat exchanger 5a. The steam is heated in the first heat exchanger 5a by recovery of heat from the dihydrogen circulating in the first heat exchanger 5a. Superheated steam leaves the first heat exchanger 5a through the fluid connection F and enters, preferably directly, into the second heat exchanger 5b. The steam is heated again in the second heat exchanger 5b by recovery of heat from the dihydrogen circulating in the second heat exchanger 5b. The superheated steam leaves the second heat exchanger 5b through the fluid connection G and enters, if necessary, preferably directly into the electric heater 14. The electric heater 14 ensures a final temperature increase, possibly necessary, so that the steam reaches a predefined target temperature at which it enters the electrolyzer 1. The steam leaves the electric heater 14 through the fluid connection H and enters, preferably directly, into the electrolyzer 1.

[0204] In operation, according to the second embodiment shown in Fig. 2, liquid water reaches the first supply line 2 in water vapor, more specifically through a fluid connection to the first part. The liquid water arrives through fluid connection I and supplies the two branches of the first supply line 2.

[0205] The water circulating in the fluid connection I enters the fluid connection J, preferably directly, and thus enters the reducer 40. The liquid water is depressurized at the outlet of the reducer 40. The depressurized water enters through the fluid connection J into the second intermediate steam generator 60. In the second intermediate steam generator 60, the depressurized water is heated thanks to the inlet of the heat quantity recovered in the first dihydrogen discharge line 3, in particular via the third intermediate exchanger 8, and optionally via the ninth intermediate exchanger 36, the eleventh intermediate exchanger 38, the twelfth intermediate exchanger 39. The superheated liquid water leaves the second intermediate steam generator 60 through the fluid connection K and enters, preferably directly, into the condenser 23. In the condenser 23, the depressurized superheated liquid water is heated by the condenser 23 of the heat pump. The superheated liquid water leaves the condenser 23 through the fluid connection L and enters, preferably directly, into the electric steam generator 28. When the electric steam generator 28 is in operation, the superheated liquid water requires an additional heat inlet, so that the water leaves the electric steam generator 28 through the fluid connection M and enters, preferably directly, into the compressor 41. The compressor 41 makes it possible to increase the pressure of the water circulating in the reduced pressure section to 1 atmosphere. The water vapor at atmospheric pressure leaves the compressor 41 through the fluid connection N and enters, preferably directly, into the first heat exchanger 5a of the first heat exchange module 5.

[0206] In the other branch, the water circulating in the fluid connection I enters the fluid connection O, preferably directly, and preferably directly into the first intermediate steam generator 50. In the first intermediate steam generator 50, the water is heated at atmospheric pressure by the heat recovered in the first dihydrogen discharge line 3, in particular by the first intermediate exchanger 6, and optionally by the eighth intermediate exchanger 35, the tenth intermediate exchanger 37, the fourth intermediate exchanger 9. The water is advantageously converted into steam in the first intermediate steam generator 50 and leaves there through the fluid connection P, entering preferably directly into the fluid connection N.

[0207] The water vapor is heated in the first heat exchanger 5a by recovery of heat from the dihydrogen circulating in the first heat exchanger 5a. The superheated water vapor leaves the first heat exchanger 5a through the fluid connection F and enters, preferably directly, into the second heat exchanger 5b. The water vapor is heated again in the second heat exchanger 5b by recovery of heat from the dihydrogen circulating in the second heat exchanger 5b. The superheated water vapor leaves the second heat exchanger 5b through the fluid connection G and, if necessary, enters, preferably directly, into the electric heater 14. The electric heater 14 ensures a final temperature increase, possibly necessary, so that the water vapor reaches a predefined target temperature at which it enters the electrolyzer 1. The water vapor leaves the electric heater 14 through the fluid connection H and enters, preferably directly, into the electrolyzer 1.

[0208] To move the liquid water and advantageously ensure the pressurization of the first supply line 2, one or more pumps can be arranged on the different fluid connections.

[0209] The electrolyzer 1 is supplied with a current according to a predefined voltage and intensity, making it possible to ensure the electrolysis and thus the production of dihydrogen and dioxygen.

[0210] Dihydrogen leaves the electrolyzer 1 through the first discharge line, through the fluid connection 300 and preferably enters directly into the first heat exchange module 5, preferably into the second heat exchanger 5b. Since dihydrogen leaves the electrolyzer in a hot gas state, its temperature must be reduced in order to use it and / or to store it. The heat value from the dihydrogen is therefore recovered by the first feed line, more specifically by the water vapor circulating therein. In the second heat exchanger 5b, the dihydrogen has a reduced temperature due to the transfer of heat value due to the water vapor circulating in the second heat exchanger 5b. The cooled dihydrogen leaves the second heat exchanger 5b through the fluid connection 301 and preferably enters directly into the first heat exchanger 5a. In the first heat exchanger 5a, the dihydrogen has a reduced temperature again due to the transfer of heat value due to the water vapor circulating in the first heat exchanger 5a. The cooled dihydrogen leaves the first heat exchanger 5a through the fluid connection 302 and enters, preferably directly, the first intermediate exchanger 6. By passing through the first intermediate exchanger 6, the dihydrogen is cooled as it transfers heat to the intermediate fluid circulating in the first intermediate fluid circuit.

[0211] According to the first embodiment shown in FIG. 1, dihydrogen leaves the first intermediate exchanger 6 through the fluid connection 303 and preferably enters directly into the second intermediate exchanger 7. In this second intermediate exchanger 7, dihydrogen is cooled when transferring heat to the intermediate fluid circulating in the intermediate fluid circuit 32. Dihydrogen leaves the second intermediate exchanger 7 through the fluid connection 304 and preferably enters directly into the first air cooler 16. Dihydrogen leaves the first air cooler 16 through the fluid connection 305 and preferably enters directly into the liquid / gas separator 17, ensuring the condensation of dihydrogen. Dihydrogen leaves the liquid / gas separator 17 through the fluid connection 306 and, if necessary, undergoes another compression, taking into account another condensation. In this case, dihydrogen leaves the liquid / gas separator 17 through the fluid connection 306 and preferably enters directly into the compressor 18, and therefore leaves through the fluid connection 307 and preferably enters directly into the fifth intermediate exchanger 12. By passing through the fifth intermediate exchanger 12, the dihydrogen is cooled when transferring heat to the intermediate fluid circulating in the intermediate fluid circuit 32. The dihydrogen leaves the fifth intermediate exchanger 12 through the fluid connection 308 and enters, preferably directly, the second air cooler 19, ensuring the cooling of the dihydrogen. The dihydrogen leaves the air cooler 19 through the fluid connection 309 and enters, preferably directly, the liquid / gas separator 20, ensuring the condensation of the dihydrogen. The condensed dihydrogen leaves the liquid / gas separator 20 through the fluid connection 310 and, if necessary, undergoes another compression, taking into account another condensation. In this case, the dihydrogen leaves the liquid / gas separator 20 through the fluid connection 310 and enters, preferably directly, the compressor 30, and therefore leaves through the fluid connection 311 and preferably directly enters the sixth intermediate exchanger 15. By passing through the sixth intermediate exchanger 15, the dihydrogen is cooled when transferring heat to the intermediate fluid circulating in the intermediate fluid circuit 32. The dihydrogen leaves the sixth intermediate exchanger 15 through fluid connection 312 and preferably enters directly into the second air cooler 31, ensuring cooling of the dihydrogen. The dihydrogen leaves the air cooler 31 through fluid connection 313 and preferably enters directly into the liquid / gas separator 34, ensuring condensation of the dihydrogen. The condensed dihydrogen leaves the liquid / gas separator 34 through fluid connection 314 and can be used or stored.The condensed liquid water recovered from the liquid / gas separators 17 , 20 , 34 can be recycled in the first water vapor supply line 2 by fluid connection with a water recycle line 21 .

[0212] According to the second embodiment shown in FIG. 2, dihydrogen leaves the first intermediate exchanger 6 through the fluid connection 315 and preferably enters directly into the third intermediate exchanger 316. Dihydrogen leaves the third intermediate exchanger 316 and preferably enters directly into the second intermediate exchanger 7. Dihydrogen leaves the second intermediate exchanger 7 through the fluid connection 304 and preferably enters directly into the air cooler 16. Dihydrogen leaves the first air cooler 16 through the fluid connection 305 and preferably enters directly into the liquid / gas separator 17, ensuring the condensation of dihydrogen. Dihydrogen leaves the liquid / gas separator 17 through the fluid connection 306 and, if necessary, undergoes another compression, taking into account another condensation. In this case, dihydrogen leaves the liquid / gas separator 17 through the fluid connection 306 and preferably enters directly into the compressor 18, and therefore leaves through the fluid connection 317 and preferably enters directly into the eighth intermediate exchanger 35. Dihydrogen leaves the eighth intermediate exchanger 35 through the fluid connection 318 and preferably enters directly into the ninth intermediate exchanger 36. Dihydrogen leaves the ninth fluid connection 36 through the fluid connection 319 and preferably enters directly into the fifth intermediate exchanger 12. By passing through the fifth intermediate exchanger 12, dihydrogen is cooled when transferring heat to the intermediate fluid circulating in the intermediate fluid circuit 32. Dihydrogen leaves the fifth intermediate exchanger 12 through the fluid connection 308 and preferably enters directly into the second air cooler 19, ensuring the cooling of the dihydrogen. Dihydrogen leaves the air cooler 19 through the fluid connection 309 and preferably enters directly into the liquid / gas separator 20, ensuring the condensation of the dihydrogen. The condensed dihydrogen leaves the liquid / gas separator 20 through the fluid connection 310 and, if necessary, undergoes another compression to allow for another condensation. In this case, dihydrogen leaves the liquid / gas separator 20 through the fluid connection 310 and preferably enters the compressor 30 directly and therefore leaves through the fluid connection 320. By passing through the fifth intermediate exchanger 12, the dihydrogen is cooled when transferring heat to the intermediate fluid circulating in the intermediate fluid circuit 32. The dihydrogen leaves the fifth intermediate exchanger 12 through the fluid connection 308 and preferably enters directly into the second air cooler 19, ensuring the cooling of the dihydrogen. The dihydrogen leaves the air cooler 19 through the fluid connection 309 and preferably enters directly into the liquid / gas separator 20, ensuring the condensation of the dihydrogen.The condensed dihydrogen leaves the liquid / gas separator 20 through the fluid connection 310 and, if necessary, undergoes another compression, taking into account another condensation. In this case, dihydrogen leaves the liquid / gas separator 20 through the fluid connection 310 and preferably enters directly into the compressor 30 and therefore exits through the fluid connection 320. Dihydrogen preferably enters directly into the tenth intermediate exchanger 37. Dihydrogen leaves the tenth intermediate exchanger 37 through the fluid connection 321 and preferably enters directly into the eleventh intermediate exchanger 38. Dihydrogen leaves the eleventh intermediate exchanger 38 through the fluid connection 322 and preferably enters directly into the sixth intermediate exchanger 15. Dihydrogen leaves the sixth intermediate exchanger 15 through the fluid connection 312 and preferably enters directly into the second air cooler 31, ensuring the cooling of the dihydrogen. The dihydrogen exits the air cooler 31 through fluid connection 313 and preferably enters a liquid / gas separator 34 to ensure condensation of the dihydrogen. The condensed dihydrogen exits the liquid / gas separator 34 through fluid connection 314 and can be used or stored.

[0213] The dioxygen produced by the electrolyzer passes through the first discharge line 3, exits through the fluid connection 100 and preferably enters directly into the second heat exchange module 11, preferably the second heat exchanger 11b. Since the dioxygen leaves the electrolyzer in a hot gas state, its temperature must be reduced in order to be discharged into the air. The heat value from the dioxygen is therefore advantageously recovered by the second feed line 10, more particularly by the air circulating therein. In the second heat exchanger 11b, the dioxygen has a reduced temperature due to the transfer of heat value for the air circulating in the second heat exchanger 11b. The cooled dioxygen leaves the second heat exchanger 11b through the fluid connection 101 and preferably enters directly into the first heat exchanger 11a. In the first heat exchanger 11a, the dioxygen has a reduced temperature again due to the transfer of heat value for the air circulating in the first heat exchanger 11a. The cooled dioxygen advantageously leaves the first heat exchanger 11a through the fluid connection 102 and enters, preferably directly, the fourth intermediate exchanger 9 of the recovery module. By passing through the fourth intermediate exchanger 9, the dioxygen has a temperature again reduced by the transfer of heat to the liquid water circulating in the intermediate exchanger 9.

[0214] According to the first embodiment shown in Fig. 1, air leaves the intermediate exchanger 9 through the fluid connection 103 and preferably enters directly into the fourth intermediate exchanger 29. In the seventh intermediate exchanger 29, the dihydrogen is cooled while transferring heat to the intermediate fluid circulating in the intermediate fluid circuit 32. The dihydrogen leaves the seventh intermediate exchanger 29 through the fluid connection 104 and is discharged into the air.

[0215] According to the second embodiment shown in Fig. 2, air leaves the fourth intermediate exchanger 9 through the fluid connection 105 and preferably enters directly into the twelfth intermediate exchanger 39. Air leaves the second intermediate exchanger 39 through the fluid connection 106 and preferably enters directly into the seventh intermediate exchanger 29. Dihydrogen leaves the seventh intermediate exchanger 29 through the fluid connection 104 and is discharged into the air.

[0216] According to an option, the electrolyzer 1 is supplied with air. The air arrives through the second supply line 10. Advantageously, the air passes through a second heat exchanger, instead of the air cooler 16, recovering heat from the dihydrogen circulating in the heat exchanger. This first heat exchange ensures a first heating of the air. The air leaves the heat exchanger through a fluid connection 110 and enters, preferably directly, into the compressor 30. According to the illustrated option, the air is compressed by the compressor 30 and its temperature is increased. The air enters the compressor 30 through a fluid connection 110. The air leaves the compressor 30 through a fluid connection 111 and preferably directly enters the second heat exchange module 11, preferably into the first heat exchanger 11a. The air is heated in the first heat exchanger 11a by recovery of heat from the dioxygen circulating in the first heat exchanger 11a. The superheated air leaves the first heat exchanger 11a through the fluid connection 112 and preferably enters directly into the second heat exchanger 11b. The air is heated again in the second heat exchanger 11b by recovery of heat from the dioxygen circulating in the second heat exchanger 11b. The superheated air leaves the second heat exchanger 11b through the fluid connection 113 and, if necessary, enters preferably directly into the electric heater 13. The electric heater 13 ensures a final temperature increase, possibly necessary, so that the air reaches a predefined target temperature entering the electrolyzer 1. The air leaves the electric heater 13 through the fluid connection 114 and preferably enters directly into the electrolyzer 1. [Explanation of symbols]

[0217] 1 electrolytic cell 2. Steam supply line 3. Dioxygen exhaust line 4. Dihydrogen Discharge Line 5a First heat exchanger of the first heat exchange module 5b second heat exchanger of the first heat exchange module 6 First Intermediate Exchanger 7 Second Intermediate Exchanger 8. Third Intermediate Exchanger 9 Fourth Intermediate Exchanger 10 Air supply line 11a: first heat exchanger of the second heat exchange module 11b second heat exchanger of the second heat exchange module 12 Fifth Intermediate Exchanger 13 Electric heater 14 Electric heater 15 6th Intermediate Exchanger 16 Air Cooler 17 Liquid / Gas Separator 18 Compressor 19 Air Cooler 20 Liquid / Gas Separator 21 Water recycling line 22 Compressor 23 Condenser 24 Reducer 25 Evaporator 26 Compressor 27 Fluid circuit 28 Electric Steam Generator 29 7th Heat Exchanger 30 Compressor 31 Air Cooler 32 Third intermediate fluid circuit 33 Pump 34 Separator 35 8th Intermediate Exchanger 36 9th Intermediate Exchanger 37 10th Intermediate Exchanger 38 11th Intermediate Exchanger 39 12th Intermediate Exchanger 40 Reducer 41 Compressor 50 First low pressure steam generator 60 Second low pressure steam generator A fluid connection going into the condenser 23 B. Fluid connection between the condenser 23 and the first intermediate generator 50 C. Fluid connection between the first intermediate generator 50 and the electric water vapor generator 28 D. Fluid connection between the electric steam generator 28 and the first heat exchanger 5a E Fluid connection between the first heat exchanger 5a and the fluid connection D F. Fluid connection between the first heat exchanger 5a and the second heat exchanger 5b G. Fluid connection between the second heat exchanger 5b and the heater 14 H Fluid connection between heater 14 and electrolyzer 1 I. Fluid connection into first water vapor supply line 2 J Fluid connection between fluid connection I and a second intermediate generator 60, preferably comprising a reducer 40 K Fluid connection between the second intermediate generator and the condenser 23 L Fluid connection between the condenser 23 and the electric generator 28 M Fluid connection between the electric generator 28 and the compressor 41 N Fluid connection between the compressor 41 and the first exchanger 5a of the first heat exchange module 5 O Fluid connection between the fluid connection I and the first intermediate generator 50 P is a fluid connection between the first intermediate generator 50 and the fluid connection N 100 Fluid connection between electrolytic cell 1 and second heat exchanger 11b 101 Fluid connection between the second heat exchanger 11b and the first heat exchanger 11a 102 Fluid connection between the first heat exchanger 11a and the intermediate exchanger 9 103 Fluid connection between intermediate exchanger 9 and intermediate exchanger 29 104 Outlet fluid connection of heat exchanger 29 105 Fluid connection between intermediate exchanger 9 and intermediate exchanger 39 106 Fluid connection between intermediate exchanger 29 and intermediate exchanger 39 110 Inlet fluid connection at compressor 30 111 Fluid connection between the condenser 30 and the first heat exchanger 11a 112 Fluid connection between the first heat exchanger 11a and the second heat exchanger 11b 113 Fluid connection between the second heat exchanger 11b and the heater 13 114 Fluid connection between heater 13 and electrolytic cell 1 200 Fluid connection between the compressor 26 and the condenser 23 201 Fluid connection between the condenser 23 and the reducer 24 202 Fluid connection between the reducer 24 and the evaporator 25 203 Fluid connection between the evaporator 25 and the compressor 26 300 Fluid connection between the electrolytic cell 1 and the second heat exchanger 5b 301 Fluid connection between the second heat exchanger 5b and the first heat exchanger 5a 302 fluid connection between the first heat exchanger 5a and the first intermediate exchanger 6 303 Fluid connection between the first intermediate heat exchanger 6 and the second intermediate heat exchanger 7 304 Fluid connection between the second intermediate heat exchanger 7 and the air cooler 16 305 Fluid connection between the air cooler 16 and the liquid / gas separator 17 306 Fluid connection between the liquid / gas separator 17 and the compressor 18 307 fluid connection between the compressor 18 and the fifth intermediate exchanger 12 308 fluid connection between the fifth intermediate exchanger 12 and the air cooler 19 309 Fluid connection between the air cooler 19 and the liquid / gas separator 20 310 Fluid connection between the liquid / gas separator 20 and the compressor 22 311 fluid connection between the compressor 22 and the sixth intermediate exchanger 15 312 a fluid connection between the sixth intermediate exchanger 15 and the air cooler 31 313 Fluid connection between the air cooler 31 and the liquid / gas separator 34 314 Dihydrogen outlet fluid connection of liquid / gas separator 34 315 Fluid connection between the first intermediate exchanger 6 and the third intermediate exchanger 8 316 Fluid connection between the third intermediate heat exchanger 8 and the second intermediate heat exchanger 7 317 fluid connection between the compressor 18 and the eighth intermediate exchanger 35 318 fluid connection between the eighth intermediate exchanger 35 and the ninth intermediate exchanger 36 319 fluid connection between the ninth intermediate exchanger 36 and the fifth intermediate exchanger 12 320 fluid connection between the compressor 22 and the tenth intermediate exchanger 37 321 fluid connection between the tenth intermediate exchanger 27 and the eleventh intermediate exchanger 38 322 fluid connection between the eleventh intermediate exchanger 38 and the sixth intermediate exchanger 15 400 fluid connection between the outlet of the second intermediate exchanger 7 and the evaporator 25 401 Fluid connection between the evaporator 25 and the inlet of the second intermediate exchanger 7 402 a fluid connection between the outlet of the fifth intermediate exchanger 12 and the evaporator 25 403 Fluid connection between the evaporator 25 and the inlet of the fifth intermediate exchanger 12 404 a fluid connection between the outlet of the sixth intermediate exchanger 15 and the evaporator 25 405 Fluid connection between the evaporator 25 and the inlet of the sixth intermediate exchanger 15 406 a fluid connection between the outlet of the seventh intermediate exchanger 29 and the evaporator 25 407 Fluid connection between the evaporator 25 and the inlet of the seventh intermediate exchanger 29 410 Main branch from evaporator 25 to intermediate exchanger 411 Main branch from intermediate exchanger to evaporator 25 500 Fluid connection between the outlet of the first intermediate exchanger 6 and the first intermediate generator 50 501 Fluid connection between the first intermediate generator 50 and the inlet of the first intermediate exchanger 6 502 a fluid connection between the outlet of the fourth intermediate exchanger 9 and the first intermediate generator 50 503 a fluid connection between the first intermediate generator 50 and the inlet of the fourth intermediate exchanger 9 504 a fluid connection between the outlet of the eighth intermediate exchanger 35 and the first intermediate generator 50 505 Fluid connection between the first intermediate generator 50 and the inlet of the eighth intermediate exchanger 35 506 a fluid connection between the outlet of the tenth intermediate exchanger 37 and the first intermediate generator 50 507 a fluid connection between the first intermediate generator 50 and the inlet of the tenth intermediate exchanger 37 510 main branch from first intermediate generator 50 to intermediate exchange 511 main branch from the intermediate exchanger to the first intermediate generator 50 600 Fluid connection between the outlet of the third intermediate exchanger 8 and the second intermediate generator 60 601 Fluid connection between the second intermediate generator 60 and the inlet of the third intermediate exchanger 8 602 a fluid connection between the outlet of the twelfth intermediate exchanger 39 and the second intermediate generator 60 603 a fluid connection between the second intermediate generator 60 and the inlet of the twelfth intermediate exchanger 39 604 a fluid connection between the outlet of the ninth intermediate exchanger 36 and the second intermediate generator 60 605 a fluid connection between the second intermediate generator 60 and the inlet of the ninth intermediate exchanger 36 606 a fluid connection between the outlet of the eleventh intermediate exchanger 38 and the second intermediate generator 60 607 a fluid connection between the second intermediate generator 60 and the inlet of the eleventh intermediate exchanger 38 610 Main branch from second intermediate generator 60 to intermediate exchange 611 main branch from the intermediate exchanger to the second intermediate generator 60

Claims

1. A high temperature electrolytic cell (HTE) (1); a first water vapor supply line (2) of the electrolytic cell configured to supply water vapor to the electrolytic cell (1); a first hydrogen discharge line (4) of the electrolyser (1) configured to discharge hydrogen (H2) from the electrolyser; a second oxygen discharge line (3) of the electrolytic cell configured to discharge oxygen (O2) from the electrolytic cell (1); a first heat exchange module (5) configured to ensure heat exchange between the first water vapor supply line (2) and the first hydrogen discharge line (4); A system comprising: a first module for recovering thermal energy from the hydrogen at the outlet of the first heat exchange module (5) for the first water vapor supply line (2), said first module comprising: a first intermediate exchanger (6) arranged on the first hydrogen discharge line (4) downstream of the first heat exchange module (5) and configured to transfer thermal energy from the hydrogen to an intermediate fluid; a first intermediate steam generator (50) arranged on the first steam supply line (2) and configured to transfer thermal energy from the intermediate fluid to liquid water; a first intermediate fluid circuit configured to receive an intermediate fluid and ensure a fluid connection between the first intermediate exchanger (6) and the first intermediate steam generator (50); A first module comprising: a third module for recovering thermal energy from the hydrogen at the outlet of the first heat exchange module (5) for the first water vapor supply line (2), said third module comprising a heat pump and an intermediate circuit, said intermediate circuit comprising: a second intermediate exchanger (7) arranged on the first hydrogen discharge line (4) downstream of the first heat exchange module (5) and configured to transfer thermal energy from the hydrogen to an intermediate fluid; a third intermediate fluid circuit (32) configured to receive an intermediate fluid and to ensure a fluid connection between the second intermediate exchanger (7) and the heat pump; Equipped with The heat pump, a fluid circuit (27) configured to receive a heat transfer fluid; an evaporator (25) arranged on the third intermediate fluid circuit (32) downstream of the second intermediate exchanger (7) and configured to transfer thermal energy from the intermediate fluid to the heat transfer fluid; a compressor (26) configured to compress the heat transfer fluid; a condenser (23) arranged on the first steam supply line (2) upstream of the first heat exchange module (5) and configured to transfer thermal energy from the heat transfer fluid to liquid water; a reducer (24) configured to reduce the heat transfer fluid; Equipped with the fluid circuit (27) is configured to fluidly connect the evaporator (25) to the compressor (26), the compressor (26) to the condenser (23), the condenser (23) to the reducer (24), and the reducer (24) to the evaporator (25). a third module; and a fifth intermediate exchanger (12) arranged on the first hydrogen discharge line (4) downstream of the second intermediate exchanger (7) in parallel with the second intermediate exchanger (7) on the third intermediate fluid circuit (32) and configured to transfer thermal energy from the hydrogen to the intermediate fluid; A system comprising:

2. 2. The system according to claim 1, further comprising a sixth intermediate exchanger (15) arranged on the first hydrogen discharge line (4) downstream of the fifth intermediate exchanger (12) in parallel with the second intermediate exchanger (7) and the fifth intermediate exchanger (12) on the third intermediate fluid circuit (32) and configured to transfer thermal energy from the hydrogen to the intermediate fluid.

3. 3. The system according to claim 1 or 2, comprising an electric steam generator (28) arranged on the first steam supply line (2) upstream of the first heat exchange module (5).

4. The system of claim 3, wherein the electric steam generator (28) is disposed downstream of the first intermediate steam generator (50).

5. A second pressure reduction module for recovery of thermal energy from the hydrogen at the outlet of the first heat exchange module for the first water vapor supply line, the second pressure reduction module comprising: a third intermediate exchanger (8) arranged on the first hydrogen discharge line (4) downstream of the first heat exchange module (5) and configured to transfer thermal energy from the hydrogen to an intermediate fluid; a reducer (40) and a compressor (41) arranged on the first steam supply line (2) upstream of the first heat exchange module (5) and together defining a reduced pressure section of the first steam supply line (2); a second intermediate steam generator (60) arranged on the reduced pressure section of the first steam supply line (2) and configured to transfer thermal energy from the intermediate fluid to the liquid water; a second intermediate fluid circuit configured to receive an intermediate fluid and to ensure a fluid connection between the third intermediate exchanger (8) and the second intermediate steam generator (60); The system according to claim 1 , comprising:

6. 6. The system of claim 5, wherein the electric steam generator (28) is disposed on the reduced pressure section downstream of the second intermediate steam generator (60).

7. 7. The system according to claim 5 or 6, wherein the first steam supply line (2) comprises a main branch in which the first intermediate steam generator (50) is arranged and a reduced pressure branch comprising the reduced pressure portion, the main branch and the reduced pressure branch being arranged in parallel.

8. 8. The system according to any one of claims 1 to 7, comprising a second air supply line (10) of the electrolyser (1) configured to supply air to the electrolyser (1).

9. 9. The system according to claim 8, comprising a second heat exchange module (11) configured to ensure heat exchange between the second air supply line (10) and the second oxygen exhaust line (3).

10. 10. The system according to claim 1, further comprising a fourth intermediate heat exchanger (9) arranged in parallel with the first intermediate exchanger (6) between the second oxygen discharge line (3) and the first intermediate fluid circuit.

11. 11. The system according to claim 10, comprising a seventh intermediate exchanger (29) arranged on the second oxygen discharge line (3) downstream of the fourth intermediate heat exchanger (9) in parallel with the second intermediate exchanger (7) on the third intermediate fluid circuit (32) and configured to transfer thermal energy from the oxygen to the intermediate fluid.

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