CA2663583A1 - Method of generating an energy source from a wet gas flow - Google Patents

Abstract

A method of generating energy from an initial gas stream comprising water vapor (H2O), said process comprising deoxidizing at least a portion of said water vapor (H2O) by passing said initial gas stream through a layer of high temperature material, called thermal base, essentially comprising carbon at high temperature, the deoxidation adite allowing to obtain a first gaseous stream comprising hydrogen (H2) obtained by reacting said water vapor (H2O) with said carbon elements. The initial flow may be a gas stream that has been used to treat a wood load (B1). The hydrogen (H2) obtained constitutes a source of energy and can then be used to produce energy by means such as a gas boiler, a gas turbine, a fuel cell, a gas engine, turbo-alternator (TAV), etc.

Description

A method of generating an energy source from a wet gas stream The present invention relates to a method of generating a source of renewable energy from a gaseous flow and the application of this energy source for high efficiency electricity generation. She aims also a system implementing the method according to the invention.
The field of the invention is the field of generating a source energy. The invention applies particularly to generation of uiie source of energy from a gas stream, comprising water vapor, and having been used in any treatment, or produced by a process or any system.
Currently, there are many flow production systems gaseous energy, especially from water or steam of water. Most of these processes and systems implement complex reaction techniques that require energy inputs and various raw materials, downstream and upstream of the reaction. Setting most of these processes and systems must, in most cases, be in a place other than that of exploitation of the product of the reaction.
The exploitation of this source of energy is, in most cases, dedicated the production of a thermodynamic gas flow, which is generally water vapor, producing mechanical work or electricity.
However, these methods and systems can not recover that a part of the thermal energy of the gas stream comprising the water vapour. Moreover, the efficiency of these processes and systems is little Student. For example, in most processes and systems currently known, the electricity production yield does not exceed 60%.
These processes and systems have significant losses that decrease their attractiveness.
An object of the invention is to propose a method and a system to generate a source of energy from a gas stream water vapor with better performance than the current processes and systems.

-2-Another object of the invention is to propose a method and a system which make it possible to generate a source of energy from a gaseous flow of simpler way.
The invention proposes to remedy the aforementioned problems by a method of generating energy from a gas flow, said initial, comprising water vapor, the process comprising deoxidation at least part of the water vapor by passing the initial gas stream through a layer of redox material at high temperature, so-called thermal base, essentially comprising carbon elements at high temperature, deoxidation to obtain a first flow gas comprising hydrogen obtained by reaction of water vapor with high temperature carbon elements.
The process according to the invention makes it possible to generate hydrogen from water vapor present in the initial gas stream, thanks to elements carbon at high temperature. The hydrogen generated is the source of energy, which represents a very important energy value. The method according to the invention makes it possible to recover not only a large part of the thermal energy of the water vapor present in the flow initial, but also a lot of the deoxidation energy of the molecule H2O by the generation of hydrogen from this water vapor. So, for a given quantity of steam, the process according to the invention generates more energy than current processes and systems. Of hydrogen, the vector of this energy, is exploitable in many known industrial systems.
The initial gas stream may comprise water vapor from of an industrial process of the place of implantation, the recycling of the steam water after combustion of hydrogen, or thermomechanical means Spraying a volume of water at the start of the system.
In the process according to the invention, the thermal base comprises essentially carbon elements at high temperature, and allows for provide in a single system, the thermal energy and the elements of carbon to achieve the deoxidation of water vapor and the production of H2. The carbon elements can be those of the chemical composition

-3-known raw materials such as coal, lignin, peat, plant or animal biomass.
Advantageously, given the exploitable energy value generated hydrogen, and the energy used for the generation of this hydrogen, the process according to the invention makes it possible to achieve a exploitable energy higher than current processes and systems.
In the process according to the invention the thermal base comprising carbon at high temperature allows, on the one hand to raise the temperature of the water vapor contained in the initial flow to create the temperature necessary for the deoxidation of this water vapor, and on the other hand provide the carbon elements that are involved in this deoxidation. The temperature at the thermal base is such that the water vapor passing through this thermal base is in reaction with the elements of carbon at high temperatures so as to produce hydrogen by the following deoxidation reactions:
C + H20 -> CO + H2: endothermic reaction (- 131 kJ) CO + HZO -> CO2 + H2: exothermic reaction (+ 40 kJ) The balance of previous deoxidation reactions is therefore:
C + 2 H20 -> CO2 + 2 H2: endothermic reaction (- 91 kJ) This reaction therefore requires a thermal booster of 91 k] so that the disproportionation, formulated above, is carried out. This energy is provided by burning at least a portion of the thermal base.
The method according to the invention may further comprise a step separating hydrogen from other elements contained in the gas stream after deoxidation of the water vapor. This separation can be achieved commercially available devices that can be work easily.
Advantageously, the method according to the invention may comprise a storage of hydrogen, obtained during the separation step.
Advantageously, the process according to the invention can understand a generation of electricity in a fuel cell from at least part of the hydrogen, this generation also producing a reaction gas. The reaction gas essentially comprises water vapor that can be recycled and deoxidized through the base

-4-thermal energy to produce hydrogen that will again be used to generate electricity in the fuel cell, in a continuous cycle.
The method according to the invention can advantageously comprise in in addition to a combustion of at least a portion of the hydrogen in a gas boiler, said combustion producing thermal energy and a combustion gas comprising steam at high temperature and low pressure. The combustion of hydrogen can also be achieved in a gas turbine, a gas engine, or a conventional boiler of production of water vapor.
In one embodiment of the method according to the invention, the Hydrogen combustion, in the steam boiler, can be realized under 02. In this embodiment, the combustion gas flow does not practically includes only water vapor at very high temperatures and low pressure.
In a second embodiment of the method according to the invention, the Hydrogen combustion can be performed under air.
Advantageously, at least a portion of the thermal energy produced by the combustion of hydrogen can be used to conditioning a thermodynamic fluid into a second gas stream essentially comprising high temperature water vapor and high pressure.
At least part of the high temperature and high water vapor pressure can also be used in a system dedicated to the production mechanical and / or electrical energy.
Advantageously, at least part of the water vapor contained in the second gas stream is used to generate electricity in a steam turbine, or a turboalternator, this electricity generation further comprising generating a third gas stream comprising low pressure and low temperature water vapor. The couple temperature / pressure that can be obtained in the system and process according to the invention, can reach very important levels which allow to produce electricity, to the highest efficiency of existing and future systems and increase the production yield electricity compared to the thermal potential originally implemented.

-5-The method according to the invention may further comprise a compressing at least a portion of the low temperature water vapor and low pressure contained in the third gas stream leading the so-called water vapor at a condensing pressure. This compression can be realized in compressor means arranged at the outlet of a turbine with steam.
Advantageously, the process according to the invention can include recovery of at least a portion of the energy of condensation of the water vapor obtained after compression.
The process may further include raising the temperature at least a portion of the water vapor contained in the third stream.
Advantageously, at least part of the water vapor contained in the combustion gas can be deoxidized by passing said water vapor through the thermal base. Indeed the process according to the invention may comprise a recycling of at least a portion of the combustion comprising water vapor, by passing at least one part of this gas through the redox thermal base, for a further deoxidation of said vapor in this gas, this deoxidation again producing hydrogen. Permanent recycling of flows gas logically restores the full energy potential they less the losses inherent in the systems and equipment used.
for the invention. As a result, the entire thermal capacity residual water vapor can thus be recovered at the thermal base and comes in deduction of the energy to be supplied to condition the elements of carbon redox and allow the disproportionation or deoxidation water vapor. The hydrogen obtained is again transferred to energy cogeneration system, and this in a continuous cycle.
In this recycling mode, the thermal base must be suitable for deoxidize water vapor continuously, the amount of carbon at high temperature must therefore be sufficient. Carbon supply at high temperature must be continuous.
In a particular embodiment, at least a portion of the water vapor contained in the flue gas may be mixed with least part of the water vapor obtained in a peripheral system

-6-whatever, such as a plant biomass dehydration system or liquid phase water supply and evaporation system in a heat exchanger using the thermal surplus of the system according to the invention. The mixture can then be deoxidized through the thermal base and start a new cycle in the process according to the invention, and this in continuous cycle Advantageously, at least part of the water vapor of the third stream, compressed to a condensing pressure and then raised to temperature, can be recycled and used to produce electricity in a steam turbine, after a rise in its temperature and its pressure. The rise in temperature of the water vapor can be achieved thanks to the thermal energy present at the thermal base or thanks to the thermal energy obtained by burning hydrogen in a gas boiler, or both.
Advantageously, the method according to the invention may comprise a generation of the thermal base by combustion of plant biomass or of coal.
The combustion of biomass can be carried out under 02 or under air.
Biomass whose combustion generates the thermal base may include plant biomass whose moisture has been reduced at prior art, such as air-dried biomass, of the dried biomass in a processing unit, roasted biomass, etc.
Advantageously, the initial gas flow may comprise at least one part of a gaseous flow of treatment of a load of biomass, such as the gaseous flow of dehumidification, drying or roasting of a biomass load. In this case, the water vapor present in the flow The initial gas comes from dried, dehumidified or roasted biomass.
The initial gas stream may comprise CO2 or any other gas a neutral vector having served as a heat transfer vector for dehydration and treatment. However, the thermal base comprising elements of carbon at high temperature, it is better that the initial gas flow includes CO2. In addition, it is more advantageous than the initial gas flow includes CO2, since the separation of hydrogen from C02 is an operation known to those skilled in the art and easily feasible.

-7-After the separation of hydrogen and CO 2, at least a part of the C02 can also transit through at least one heat exchanger for reach a temperature necessary for a predetermined treatment and be directly used in the treatment in question. The treatment in question can be roasting, drying, dehumidification, etc. a charge of wood for example.
Advantageously, after the separation of hydrogen and CO 2, least part of the CO2 can be condensed and recovered, for example in liquid phase.
The thermal base used in the process according to the invention can be ignited at a temperature that is set by injection of oxygen in the heart of said base. This oxygen injection can be used to control the temperature at the heart of the base, upstream of the base or downstream of the thermal base.
According to another aspect of the invention, a system of generation of energy from a gaseous flow, said initial, comprising water vapor, the system comprising:
means for generating a high-material layer temperature, called thermal base, essentially comprising high temperature carbon;
means for passing said gas stream through said thermal base, the passage allowing a deoxidation of least part of the water vapor, deoxidation to obtain hydrogen by reaction of the vapor of water with carbon.
In a particularly advantageous version of the invention, the generation means comprise a thermal generator provided for generate at least a portion of the thermal base, the generator being also intended to deoxidize at least a portion of the water vapor that flows through the thermal base. Indeed, the thermal base can be found within the thermal generator.
The thermal generator may comprise a thermal reactor or a solid fuel fireplace or a hybrid device, allowing the combustion of a solid fuel, in particular plant biomass

-8-whose moisture has been reduced by prior treatment. This combustion produces high temperature carbon elements, at least one of which part can be used to achieve the thermal base, and used as carbon redox at high temperature.
Advantageously, the heat generator may be provided with a system for regulating the temperature of the walls, by circulating a coolant. The generator may include double walls between heat transfer liquid, for example water under pressure, can circulate. The coolant can also be thrown on the walls of the thermal generator.
In a particular version of the invention, the thermal generator may include a grate grate provided to receive the thermal base and arranged to carry out the transfer of combustion gases from a charge of biomass realizing at least partly the thermal base and the gas flow initial.
The grate hearth may advantageously be provided with a system of cooling by circulation of a coolant in the grids of the home.
The thermal generator may also include means of oxygen injection. The injection of oxygen can, on the one hand, serve to achieve the combustion of a solid fuel for the generation of the thermal base, and secondly, the regulation of the temperature at the of the thermal base.
The generator may also include means for capturing and separation of the hydrogen obtained by deoxidation of the water vapor.
The thermal generator may in particular comprise a chamber of the flow of gas having passed through thermal base to high temperature. This relaxation room is implemented especially to complete the disproportionation of water vapor molecules H2 residuals in contact with carbon monoxide elements from the incomplete combustion of carbon at high temperatures.
Advantageously, the heat generator may comprise at minus one heat exchanger, this heat exchanger being provided for heat exchange between the first gaseous stream, composed

-9 essentially CO2 and H2 at high temperature and a fluid coolant, which can be that of a part cooling circuit of the thermal generator system. This fluid takes care of the energy said gaseous assembly to transfer it to a system of cogeneration of electricity, for example a turboalternator.
The system according to the invention may further comprise a device of steam production, by valuing thermal energy from of any element of the system.
The system may further include storage means and / or of distribution of 02 and / or C02 Other advantages and features will appear in the examination of the a detailed description of a non-limiting embodiment, and attached drawings in which;
FIG. 1 is a schematic representation of a first mode of performing the method according to the invention using a boiler with steam;
FIG. 2 is a schematic representation of a second mode of the method according to the invention using a boiler with steam;
FIG. 3 is a schematic representation of a third mode of performing the method according to the invention using a battery combustible ; and FIG. 4 is a diagrammatic representation of a fourth mode embodiment of the method according to the invention using a battery combustible.

Figure 1 schematically shows a first mode embodiment of the method according to the invention. The system represented in figure 1 comprises a unit 1 for storing a solid fuel comprising carbon, and more particularly combustible carbon. Carbon fuel may be coal or plant biomass of which moisture has been reduced by prior treatment, such as dehumidification.

- 10-In the example of application shown in FIG. 1, the unit 1 is a unit for storing a load of raw material fuel to high carbon content B1. The charge of B2 raw material fuel high carbon content is introduced, by a regulating system B, into the reactor R where it is burned under 02. This combustible raw material is intended, on the one hand to form the thermal base and on the other hand to wear and maintain this thermal base at the process temperature. The complete combustion of this raw material under CO2 produces.
The reactor R also receives an initial gas stream F1 comprising the water vapor at high temperature and low pressure from a exchanger E2 and a mixing chamber Cm. Water vapor from E2 undergoes the redox reaction when passing through the base thermal. This disproportionation produces the first gas flow Fgl at high temperature and low pressure. This first gas flow Fgl is composed essentially H2 and COZ. H2 and CO2 are then separated into one industrial gas separator system SG.
The CO2 obtained by separation is a neutral gas stream Fn, too hot to be exploited in the state, it is cooled in an air cooler E3.
An Fnr portion of the cooled CO 2 is discarded and the rest Fns compressed in Cl compressor means and stored in S1 storage means. A
Fnsl part of stored COZ can be used as coolant flow of the system according to the invention or for the security of the system.
The hydrogen obtained is burned under O2 in a gas boiler Ch.
The combustion of hydrogen under 02 makes it possible, on the one hand, to generate a flow gcl combustion gas at very high temperature comprising essentially H20 low pressure water vapor, and secondly generate a second gas stream Fg2 essentially comprising the water vapor obtained by heating a thermodynamic fluid Fth essentially comprising water. At the outlet of the gas boiler Ch, this second gas stream Fg2 essentially comprises water vapor high temperature and very high pressure. The combustion gas Gcl, which has yielded most of its thermal potential to the second flow gaseous Fg2, still holds a significant thermal load, upon its release from the boiler Ch: about 10 to 20% of the calorific value of the combustion

-11-of HZ under 02 in the system. This combustion gas comprising water vapor is recycled to the reactor R after passing through a exchanger / mixing chamber E2 and Cm where it can be mixed with a feed F1-1 H20 liquid that serves as a backup. The liquid H 2 O is evaporated in the exchanger / mixing chamber E2 and Cm, a system Pch coupled to a heating system for the start-up phase vaporizes the filler water.
The gaseous mixture thus formed, at the outlet of the mixing chamber Cm, becomes the initial gaseous flow F1, it is at high temperature and low pressure and participates in the useful heat exchange within the thermal base. all the thermal energy contained in this gaseous mixture is thus recycled, from same as the water vapor which is again deoxidized at the passage of the thermal base and this in continuous cycle.
The second gas stream Fg2 comprising water vapor superheated and very high pressure obtained at the outlet of the gas boiler Ch drives a TAV steam turbine that generates electricity through a alternator A coupled to the system. The turbine makes it possible to exploit the essential the mechanical energy of the steam. At the outlet of the TAV steam turbine, a third gas stream Fg3 is obtained comprising water vapor at very low pressure and low temperature. This water vapor is compressed by a steam compressor C2, at a pressure sufficient to its physical change in the liquid state in the preparer / exchanger VAP. The water obtained by condensation in this pressure washer relating to the enthalpy of the residual vapor is overheated in the heat exchanger El, it is thus recycled into thermodynamic flow Fth before to be reintroduced into the secondary circuit of the gas boiler Ch.
much of the residual energy at the outlet of the steam turbine is thus recycled. Electricity useful for compression generates energy thermal, by "Joule" effect, which is exploited by the system, neutralizing so part of the impact of electricity consumption the compressor on the operating balance.
Continuous recycling of water vapor in the disproportionation cycle and CO2 generates surpluses:
- COz Fn which is cooled in an air cooler E3 (Part Fnr of this CO2 is rejected to the ecosystem, the rest Fns is compressed by

- 12-C1 compressor means and stored in means of storage 51) - H20, the permanent recycling of water vapor and combustion of the thermal base can generate excess water vapor, which will then be extracted from the recycling circuit.
Figure 2 is a schematic representation of a second mode embodiment of the method according to the invention. In this embodiment, the The system according to the invention is used for recycling a gaseous flow of treatment Ft of a biomass load B1 and for recovery of the gas flow used to treat the load of biomass.
Biomass B1 is dehydrated or roasted in the treatment 1. After treatment, the gaseous mixture extracted comprises:
the gaseous treatment flow Ft, C02 heat transfer treatment of the biomass load, and - steam from the initial biomass B1.
This gaseous set then becomes the initial gaseous stream F1 that will be recycled in the system and method according to the invention.
Part B3 of the treated biomass B1, for example in roasting or in drying, is stored. Another B2 part of the B1 biomass is introduced by a regulating system B into the reactor R where it is placed in thermal reaction under O 2 to form the thermal base of which a The purpose of this part is to carry and maintain this thermal base at process temperature. In addition, the complete combustion of biomass under 02 C0Z product that can be used as Ft heat transfer for the treatment of the biomass of origin B1.
The initial gas flow F1, comprising heat-exchange CO 2 used in the treatment of biomass B1 and water vapor extracted from biomass of origin is recycled to reactor R after heat exchange in a heat exchanger E2 and a transit in a mixing chamber Cm, explained below.
The initial gas flow is thus at high temperature when it is introduced into the reactor R. The CO2 is neutral for the reaction of deoxidation of the water vapor, but the water vapor undergoes the reaction

- 13-redox of the thermal base. This disproportionation produces a first Fgl gas stream comprising essentially H2 and CO2. H2 is separated from the other components of the first gas stream, and in particular the C02, in an industrial gas separator system SG, known to man of career. C02 can be reused as heat transfer gas Ft which will transmit its thermal capacity to the biomass to be dehydrated or roasted. At the exit of the separator SG, the C02 has yielded part of its thermal load in the El heat exchanger. However, it may still be too hot to be usable in Ft treatment gas, an injection of C0Z
cold Fnsl will then regulate it. Hydrogen is burned under 02 in a Ch gas boiler with superheated steam production at very high performance. The combustion of hydrogen under 02 allows, on the one hand, generating a combustion gas Gcl essentially comprising steam H20 high temperature / low pressure water, and secondly to generate a second gas stream Fg2 essentially comprising water vapor by heating a thermodynamic fluid Fth essentially comprising some water. At the outlet of the gas boiler Ch, this second gas stream Fg2 basically includes high temperature water vapor and very high pressure. The Gcl combustion gas that gave up most of of its thermal potential to the second gas stream Fg2, still holds a significant thermal load: 10 to 20% of the calorific value of the H2 combustion under 02. The water vapor contained in the gas of The combustion is recycled to the reactor R after passing through the mixture Cm where it will be mixed with the initial gas flow F1, that is to say, with the gaseous set for treating the original biomass: CO 2 + H 2 O
dehydration of Bi biomass. The gaseous mixture thus formed becomes the new F1 initial stream that will be recycled to the R reactor it is at high temperature and participates in the useful heat exchange within the thermal base. All the thermal energy contained in this gas mixture is thus recycled. The water vapor is again deoxidized at the passage of the thermal base and this in continuous cycle.
The second gas stream Fg2 comprising water vapor superheated at very high pressure, obtained at the outlet of the gas boiler Ch, drives a TAV steam turbine that generates electricity through

-14-alternator A coupled to the system. The turbine makes it possible to transform most of the couple "temperature / pressure" of the steam into energy mechanical system that will cause the alternator A. At the outlet of the steam turbine TAV, a third gas stream Fg3 is obtained, essentially comprising water vapor at a very low pressure and at a low temperature. This water vapor is then compressed by a steam compressor C2, at a sufficient pressure for its physical change to the liquid state in the preparator VAP: the water obtained in this preparer (at the relative pressure at the enthalpy of the residual steam) is overheated in the heat exchanger before being reintroduced into the secondary circuit of the gas boiler Ch.
Much of the residual energy at the outlet of the steam turbine is thus recycled. Electricity useful for compression generates energy thermal by "Joule" effect that is exploited by the system, neutralizing so part of the impact of electricity consumption the compressor, on the operating balance sheet.
Continuous recycling of water vapor in the disproportionation cycle and CO 2 generates surpluses. The excess water is rejected in the ecosystem. Excess CO 2 Fn is cooled in an air cooler E3.
A part Fnr of this CO2 is rejected to the ecosystem, the rest Fns is compressed by C1 compressor means and stored in means S1 storage.
FIG. 3 is a representation of a third embodiment of the process according to the invention involving a fuel cell PAC.
In the exemplary application shown in FIG. 3, unit 1 is a storage unit of a load of raw material fuel B1 at high carbon content. This raw material is a fuel to generate, at the same time the physical and chemical conditions of the disproportionation of the water vapor contained in the initial gas flow. The fuel will preferably be solid, to create the best conditions homogenization for the H20 disproportionation reaction.
The choice of fuel will be on a raw material which will preferably be renewable, ie biomass dehydrated or roasted vegetable, or peat or any other fuel with a high carbon content.

-15-The feedstock feedstock B2 with a high content of carbon is introduced, by a regulating system B, into the reactor R where it is burned under 02. The combustible raw material thus forms the basis a part of which is intended to carry and maintain the said base thermal at the process temperature. The complete combustion of this raw material under 02 produces COZ.
The reactor R also receives the initial gas stream F1 comprising the water vapor at high temperature and low pressure. Water vapor from the exchanger E undergoes the oxido-reducing reaction during the passage through the thermal base. This disproportionation produces a first gaseous flow Fgl composed essentially of H2 and C02 of the thermal reaction and disproportionation. The first gas flow Fgl is at high temperature and low pressure. H2 and C02 are separated in one SG industrial gas separator system. SG separator can do integral part of the fuel cell which he is then one of component.
The CO2 obtained Fn is cooled in an air cooler E3. A part Fnr of the cooled CO2 is rejected and the rest Fns is compressed by means C1 compressors and stored in storage means S1. A part Fnsl of stored CO2 can be used for cooling the system according to the invention or for the safety of the system.
The hydrogen obtained is introduced into the fuel cell PAC where it will be put into chemical reaction by the physical means of the system and a industrial 02 injection. This reaction allows, on the one hand, to generate electricity with a very high yield compared to the potential initially implemented and, on the other hand, to generate a flow of reaction gas Fgr comprising essentially water vapor to high temperature and low pressure.
Electricity is directly exploitable by all means conventional.
The gaseous reaction flow Fgr is thus essentially composed of high temperature and low pressure water vapor that holds a charge important thermal. This gaseous reaction flow Fgr comprising water vapor is recycled to the reactor R after passing through a exchanger / mixing chamber E2 and Cm where it is mixed with a contribution of

-16-HZ0 liquid that serves as an F1-1 supplement. The liquid H 2 O is evaporated in the exchanger / mixing chamber E2 and Cm, a Pch system, coupled to a heating system for the start-up phase, vaporizes the filler water.
The gaseous mixture thus formed, at the outlet of the mixing chamber Cm, at least partly constitutes the initial gas flow F1. This gas mixture is at high temperature and low pressure and participates in the heat exchange useful within the thermal base. All the thermal energy contained in this gaseous mixture is thus recycled.
The water vapor is recycled in the reactor R, so it is new deoxidized at the passage of the thermal base and this in cycle continued.
Continuous recycling of water vapor in the disproportionation cycle and generates surpluses:
- C02 Fn (product of the disproportionation of H20 by the thermal base, composed of carbon) which is cooled in an air cooler E3. A
part Fnr of this CO2 is released to the ecosystem, the rest Fns is compressed by C1 compressor means and stored in S1 storage means - H20, the permanent recycling of water vapor and combustion of the thermal base can generate excess water vapor, which will then be extracted from the recycling circuit.
FIG. 4 is a representation of a fourth embodiment of the process according to the invention involving a fuel cell PAC.
In this embodiment, the system according to the invention is used for the recycling of a treatment gas stream Ft of a biomass load B1 and recycling (for energy and elemental recovery) of the gas stream used for the treatment of the biomass load.
Biomass B1 is dehydrated or roasted in the treatment 1. After treatment, the gaseous mixture extracted comprises:
the treatment gas flow Ft, the heat-exchange CO 2 treatment of the biomass load B1, and - water vapor from the initial biomass B1.
This gaseous set then becomes the initial gaseous stream F1 that will be recycled in the system and method according to the invention.

- 17-Part B3 of the treated biomass B1, for example in roasting or in drying, is stored. Another part of B2 biomass is introduced by a regulating system B into the reactor R where it is placed in thermal reaction under O 2 to form the thermal base. A part of this biomass B2 is intended to carry and maintain this thermal base at the process temperature. In addition, the complete combustion of the biomass under 02 produces CO2 that can be used as a flux coolant Ft for the treatment of biomass of origin B1.
The initial gas flow F1, comprising heat-exchange CO 2 used in the treatment of biomass B1 and water vapor extracted from biomass of origin, is recycled to the reactor R after heat exchange in a heat exchanger E1 and a transit in a mixing chamber Cm, explained below.
The initial gas flow F1 is thus at high temperature when it is introduced into the reactor R. The CO2 is neutral for the thermal reaction, but the water vapor undergoes the oxydo-reductive reaction of the base thermal. This disproportionation produces a first gas flow Fgl essentially comprising H2 and CO2. H2 is then separated from other gaseous elements constituting the first stream, and in particular C02, in an industrial gas separator system SG, known to the man of the job.
CO2 can be reused as a heat-transfer gas stream Ft treatment that will transmit its thermal capacity to the biomass at dehydrate or roast. At the exit of the separator SG, the COZ yielded a part of its heat load in the E1 exchanger, it is possible, however, that is still too hot to be usable in Ft process gas, a Cold C02 injection Fnsl will then regulate it.
The hydrogen obtained is introduced into the fuel cell PAC where it will be put into chemical reaction by the physical means of the system and a industrial 02 injection. This reaction allows, on the one hand, to generate electricity with a very high yield compared to the potential energetically implemented at the base and secondly to generate a flow reaction gas Fgr comprising essentially water vapor to high temperature and low pressure.

-18-Electricity is directly exploitable by all means conventional.
The gaseous reaction stream Fgr essentially comprises steam of high temperature and low pressure water that holds a charge important thermal. This gas stream comprising water vapor is introduced into a mixing chamber Cm where it is mixed with the gas stream extracted from unit 1 of biomass treatment, and which has passed through El heat exchanger where it has acquired a significant thermal capacity.
The gaseous mixture thus formed at the outlet of the mixing box Cm, at least partly constitutes the initial gaseous flow F1 and is at high temperature and low pressure and participates in the useful heat exchange at within the thermal base. All the thermal energy contained in this gaseous mixture is thus recycled.
The water vapor is recycled and deoxidized again at the passage of the thermal base and this in continuous cycle.
An Fn part of the C0Z obtained is cooled in an air cooler E3.
An Fnr part of the cooled CO 2 is discarded and the rest Fns is compressed by Cl compressor means and stored in storage means 51.
A Fns1 part of the stored CO 2 can be used for the cooling of the system according to the invention or for the security of the system. Water in excess is also rejected to the ecosystem at the outlet of the PAC fuel cell.
The CO2, which will be used as heat transfer fluid Ft, is very high temperature at the outlet of the separator. He exchanges the biggest part of its thermal load, to the gaseous flow extracted from the treatment unit of biomass, in the heat exchanger El. This heat transfer flow will then be regulated, at the temperature useful to its exploitation, by a contribution of cold CO2 FNSL.

Naturally, the invention is not limited to the examples that we have just to describe and can be used for energy generation from all gas stream comprising steam.

Claims (18)

1) Process for generating hydrogen from a gas stream (F1), said initially consisting essentially of water vapor (H2O) and CO2, said method comprising the following steps:
a first step of deoxidation of a part of the molecules of water vapor with carbon elements at high temperature, by passing said initial gas stream (F1) through a layer of high temperature material, called base thermal, essentially comprising carbon elements at high temperature, said deoxidation providing a flow gaseous synthesis comprising on the one hand of hydrogen (H2) and carbon monoxide (CO) molecules generated by said deoxidation and, on the other hand, CO2 and residual water vapor molecules (H2O) from said stream gaseous initial, and downstream of said thermal base, a second step of deoxidation of said water vapor molecules (H2O) residues in contact with said monoxide carbon (CO) contained in the synthesis gas, second deoxidation providing a first gas stream (Fg1) comprising on the one hand hydrogen (H2) and CO2 from said second deoxidation and CO2 from the stream initial gas;
said thermal base being produced by combustion under O2 of biomass whose humidity has been diminished. 2) Method according to claim 1, characterized in that the second deoxidation is caused by a relaxation of the synthesis gas stream in a relaxation room. 3) Process according to any one of claims 1 or 2, characterized in that it further comprises a step separating hydrogen (H2) from other elements contained in the first gas stream (Fg1). 4) Method according to claim 3, characterized in that it comprises in in addition to storing hydrogen (H2). 5) Process according to any one of the preceding claims, characterized in that it comprises a generation of electricity in a battery fuel (PAC) from at least part of the hydrogen, said generation further producing a reaction gas (Fgr) comprising water vapor (H2O). 6) Process according to claim 5, characterized in that at least one part of the water vapor (H2O) contained in the reaction gas (Fgr) is recycled to be deoxidized again by passing said vapor of water (H2O) through the thermal base. 7) Method according to any one of the preceding claims, characterized in that it further comprises a combustion of at least one part of the hydrogen (H2) in a gas boiler (Ch), said combustion producing thermal energy and a combustion gas (Gc1) comprising steam (H2O) of high temperature and low water pressure. 8) Process according to claim 7, characterized in that at least one part of the thermal energy produced by the combustion of hydrogen (H2) is used to condition a thermodynamic fluid (Fth) into a second gas stream (Fg2) essentially comprising water vapor at high temperature and high pressure. 9) Method according to claim 8, characterized in that at least one part of the water vapor (H2O) contained in the second gas stream (Fg2) is used to produce electricity in a steam turbine (TAV), said production further comprising a generation of a third gas stream (Fg3) comprising low water vapor (H2O) pressure and low temperature. 10) Method according to claim 9, characterized in that it comprises in in addition to compressing at least a portion of the water vapor (H2O) low temperature and low pressure contained in the third gas stream (Fg3) causing said water vapor (H2O) to a condensing pressure. 11) Method according to claim 9, characterized in that it comprises a recovering at least a portion of the condensation energy of the water vapor obtained after compression. 12) Method according to any one of claims 10 or 11, characterized in that at least a portion of the water vapor (H2O) is used to produce electricity in a Vane Turbine (TAV). 13) Method according to any one of claims 7 to 12, characterized in that at least a portion of the water vapor (H2O) contained in the gas (Gc1) is recycled to be deoxidized again by passage of said water vapor through the thermal base. 14) Method according to any one of claims 7 to 13, characterized in that the combustion of hydrogen (H2) is carried out under O2. 15) Method according to any one of claims 7 to 13, characterized in that the combustion of hydrogen (H2) is carried out under air. 16) Method according to any one of the preceding claims, characterized in that it comprises an injection of O2 at the heart of the base said O 2 injection being carried out in such a way as to achieve a incomplete combustion of biomass (B2), said incomplete combustion producing carbon monoxide (CO) molecules participating in less in part to the deoxidation of H2O molecules. 17) Method according to any one of the preceding claims, characterized in that the initial gas stream (F1) comprises at least one part of a treatment gas stream (Ft) of a biomass feedstock (B1). 18) System comprising the means for implementing the method according to any one of the preceding claims.