INSTALLATION AND METHOD FOR PRODUCING LIQUEFIED HYDROGEN

Abstract

The invention relates to an installation for producing liquefied hydrogen having a gaseous hydrogen generator configured to produce gaseous hydrogen, a liquefier, a supply duct connecting a gaseous hydrogen outlet of the gaseous hydrogen generator to an inlet of the liquefier, the liquefier having a refrigerator having a cycle circuit configured to provide cooling power and cool the gaseous hydrogen from the supply duct with a view to the liquefaction thereof, the installation having at least one compressor for the gaseous hydrogen produced by the gaseous hydrogen generator and a buffer store configured to store the compressed gaseous hydrogen between the gaseous hydrogen generator and the liquefier, the buffer store being connected to the supply duct via a set of bypass duct(s), i.e. the buffer store and the liquefier are connected in parallel to the gaseous hydrogen outlet of the gaseous hydrogen generator.

Claims

1. An installation for producing liquefied hydrogen comprising a gaseous hydrogen generator configured to produce gaseous hydrogen, a liquefier, a supply duct connecting a gaseous hydrogen outlet of the gaseous hydrogen generator to an inlet of the liquefier, the liquefier comprising a refrigerator having a cycle circuit configured to provide cooling power and cool the gaseous hydrogen from the supply duct with a view to the liquefaction thereof, the installation comprising at least one compressor for the gaseous hydrogen produced by the gaseous hydrogen generator and a buffer store configured to store the compressed gaseous hydrogen between the gaseous hydrogen generator and the liquefier, the buffer store being connected to the supply duct via a set of bypass duct(s), the buffer store and the liquefier are connected in parallel to the gaseous hydrogen outlet of the gaseous hydrogen generator, the refrigerator being of the type having a cycle circuit configured to produce cooling power by subjecting a cycle gas to a thermodynamic cycle, the cycle circuit comprising a set of compressor(s) for the cycle gas, at least one member for cooling the compressed cycle gas and at least one member for expanding the compressed cycle gas, wherein the cycle gas is hydrogen and in that the buffer store is connected to the cycle circuit so as to supply the cycle circuit with hydrogen and/or to be supplied with hydrogen by the cycle circuit.

2. The installation of claim 1, further comprising a compressor situated on the set of bypass duct(s).

3. The installation of claim 1, in the set of bypass duct(s) further comprising a return duct configured to transfer gaseous hydrogen from the buffer store to the supply duct.

4. The installation of claim 3, wherein the return duct comprises at least one member for expanding the gaseous hydrogen from among: an expansion valve, a turbine, a turbine coupled to an electric power generator or to a compressor so as to form a turbocompressor.

5. The installation of claim 1, wherein it has at least one compressor for the gaseous hydrogen intended to supply the buffer store that is also a compressor of the set of compressor(s) for the cycle gas.

6. The installation of claim 1, wherein the supply duct has a plurality of compressors disposed in series and/or in parallel, configured to supply the buffer store and/or the cycle circuit with compressed hydrogen.

7. The installation of claim 6, wherein the set of compressor(s) for the cycle gas comprises a plurality of compressors disposed in series and/or in parallel, the installation comprising a provision duct connecting the buffer store to the inlet or to the outlet of at least one of the compressor(s) for the cycle gas and configured to allow pressurized gaseous hydrogen to be provided to the cycle circuit.

8. The installation of claim 1, wherein it has a plurality of liquefiers connected in parallel to the supply duct and also connected in parallel to the buffer store.

9. The installation of claim 1, further comprising a set of liquid hydrogen store(s) connected to an end of the supply duct leaving the liquefier and configured to collect the hydrogen liquefied by the liquefier, the installation further comprising filling circuitry connected to the set of liquid hydrogen store(s) and configured to allow the filling of tank(s), the installation comprising a set of duct(s) for recovery of the vaporization gases generated at the set of liquid hydrogen store(s) and/or at the filling circuitry, the set of duct(s) for recovery of the vaporization gases being connected to the supply circuit.

10. A method for producing liquefied hydrogen using the installation of claim 1, of the method comprising providing compressed gaseous hydrogen to the buffer store when the gaseous hydrogen generator produces a quantity of hydrogen that is above a first threshold and a step of supplying the supply duct with compressed gaseous hydrogen from the buffer store when the gaseous hydrogen generator produces a quantity of hydrogen that is below first a second threshold.

11. The method of claim 10, further comprising a step of using compressed hydrogen provided by the supply duct and/or the buffer store to supply a compression portion of a hydrogen cycle circuit of the refrigerator of the liquefier.

12. The method of claim 11, further comprising a step of compressing the gaseous hydrogen in the supply duct to a determined target pressure, for example equal to 60 bar, and in that the final compression level of the compression portion of the cycle circuit is equal to this target pressure.

13. The method of claim 12, wherein the buffer store is configured to store the gaseous hydrogen as far as a determined maximum storage pressure that is higher than the target pressure, the buffer store being configured to provide gas to the compression portion of the cycle circuit at the target pressure or at a pressure lower than the target pressure.

14. The method of claim 10, further comprising storing, in a liquid hydrogen store(s), liquid hydrogen produced by the installation and optionally a step of filling tank(s) with liquid hydrogen from the liquid hydrogen store, the method comprising a step of recovering vaporization gases generated during the storage step and/or during the filling step and a step of recycling the recovered vaporization gas into the supply duct.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0033] The invention will be understood better from reading the following description, which is given solely by way of example and with reference to the appended drawings, in which:

[0034] FIG. 1 is a schematic and partial view illustrating the structure and the operation of an installation according to a first exemplary embodiment of the invention,

[0035] FIG. 2 is a schematic and partial view illustrating the structure and the operation of an installation according to a second exemplary embodiment of the invention,

[0036] FIG. 3 is a schematic and partial view illustrating the structure and the operation of an installation according to a third exemplary embodiment of the invention,

[0037] FIG. 4 is a schematic and partial view illustrating the structure and the operation of an installation according to a fourth exemplary embodiment of the invention,

[0038] FIG. 5 is a schematic and partial view illustrating the structure and the operation of an installation according to a fifth exemplary embodiment of the invention,

[0039] FIG. 6 is a schematic and partial view illustrating the structure and the operation of an installation according to a sixth exemplary embodiment of the invention,

[0040] FIG. 7 is a schematic and partial view illustrating the structure and the operation of an installation according to a seventh exemplary embodiment of the invention,

[0041] FIG. 8 is a schematic and partial view illustrating the structure and the operation of an installation according to an eighth exemplary embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

[0042] Throughout the figures, the same references relate to the same elements.

[0043] In this detailed description, the following embodiments are examples. Although the description refers to one or more embodiments, this does not mean that the features apply only to a single embodiment. Individual features of different embodiments can also be combined and/or interchanged to provide other embodiments.

[0044] The installation 1 for producing liquefied hydrogen that is illustrated comprises a gaseous hydrogen generator 2, for example an electrolyser, configured to produce gaseous hydrogen, a liquefier 7 and a supply duct 6 connecting an outlet of the gaseous hydrogen generator 2 to an inlet of the liquefier 7.

[0045] Hereinafter, the gaseous hydrogen generator 2 is referred to as electrolyser. Of course, as a variant or in combination, this gaseous hydrogen generator 2 may have a reforming device, in particular for autothermal reforming (ATR).

[0046] The liquefier 7 comprises a refrigerator 8 having a cycle circuit configured to provide cooling power and cool the gaseous hydrogen from the supply duct 6 with a view to the liquefaction thereof.

[0047] The installation 1 comprises at least one compressor 10 for the gaseous hydrogen produced by the electrolyser 2 and at least one buffer store 9 configured to store the compressed gaseous hydrogen between the electrolyser 2 and the liquefier 7.

[0048] According to one advantageous particular feature, the buffer store 9 is connected to the supply duct 6 via a set of bypass duct(s) 19, 29, i.e. the buffer store 9 and the liquefier 2 are connected in parallel to the gaseous hydrogen outlet of the electrolyser 2.

[0049] This architecture allows better interoperability between the electrolyser 2 and the liquefier 7.

[0050] The buffer store 9 is preferably a high-pressure gas store making it possible to store compressed hydrogen when the electrolyser 2 is producing at full capacity and to return hydrogen, for example, when the production of hydrogen by the electrolyser 2 is insufficient (renewable energy which is sparingly available, for example).

[0051] As illustrated in [FIG. 1], at least one compressor 10 may be situated on the set of bypass duct(s) 19.

[0052] Furthermore, the set of bypass ducts may comprise a first duct 19 configured to fill the buffer store 9 and a return duct 29 configured to transfer gaseous hydrogen from the buffer store 9 to the supply duct 6.

[0053] The return duct 29 preferably comprises at least one member 39 for expanding the gaseous hydrogen from among: an expansion valve, a turbine, a turbine coupled to an electric power generator or to a compressor so as to form a turbocompressor.

[0054] Thus, the gaseous hydrogen stored under pressure can be recovered when hydrogen availability is low. A turbine 39 for producing electricity can make it possible to produce electricity during this return period (cf. [FIG. 2]).

[0055] As illustrated in particular in [FIG. 4] and [FIG. 8], the refrigerator 8 for cooling the hydrogen with a view to the liquefaction thereof may comprise a refrigerator of the type having a cycle circuit 16 configured to produce cooling power by subjecting a cycle gas comprising for example helium and/or hydrogen to a thermodynamic cycle.

[0056] The cycle circuit 16 of such a refrigerator 8 typically comprises a set of cycle gas compressors, at least one member 13 for cooling the compressed cycle gas (one or more heat exchangers) and at least one member 15 for expanding the compressed cycle gas (valve(s) and/or turbine(s)).

[0057] In the example in [FIG. 8], the cycle circuit 16 of the refrigerator is separate from the supply duct 6. In addition, this cycle circuit 16 is closed. After a compression 11 at ambient temperature, the cycle gas is cooled in a first heat exchanger assembly 13 (down to a first temperature, for example of the order of 80K). The cycle gas is then expanded (valve 15) and produces a cooling power that is provided to the supply duct 6 in a heat exchanger 14 that is colder (typically around 20K). The cycle gas that provided the cooling power is sent back to the compression and heats up by cooling the cycle gas stream that will be expanded. By returning to the compression, the cycle gas also cools the supply duct 6 in the opposite direction (typically countercurrent-wise).

[0058] As illustrated, the liquefier 7 may comprise at least one pre-cooling device 12 in heat exchange with the supply duct 6 and the cycle circuit 16 and configured to pre-cool the gaseous hydrogen to an intermediate temperature (80K) before it is cooled by the refrigerator 8. This pre-cooling device 12 comprises, for example, at least one from among: a nitrogen refrigeration cycle or a refrigeration cycle with a refrigeration mixture in heat exchange with a pre-cooling exchanger assembly 13 (for example in a first pre-cooling cold box).

[0059] In the example in [FIG. 4], the cycle gas is hydrogen (i.e. of the same nature as the gas to be liquefied). In this configuration, the buffer store 9 can be connected to the cycle circuit 16 so as to supply the cycle circuit 16 with hydrogen and/or to optionally be supplied with hydrogen by the cycle circuit. This means that the cycle circuit 16 may be open.

[0060] This configuration makes it possible for components of the installation 1 to be shared. Thus, at least one compressor 10 for the gaseous hydrogen intended to supply the buffer store 9 can also be a compressor of the set of compressor(s) 10, 11 for the cycle gas (cf. [FIG. 3] or [FIG. 4]). Thus, a part of the supply duct 6 may also constitute a portion of the cycle circuit 16.

[0061] This is also illustrated in [FIG. 4], in which the cycle circuit 16 of the refrigerator 8 may be partly common with the supply duct 6. Thus, for example, downstream of a pre-cooling exchanger 13, the supply duct 6 may have a cryogenic purification system 25 (of the TSA type for example) and then an expansion member 36 (valve for example) for expansion with a view to the liquefaction (cooling 14 below the critical temperature). Downstream, the supply duct 6 can supply a liquid hydrogen store 18 with liquefied hydrogen.

[0062] As illustrated, downstream of the device 25 for cryogenic purification of the gaseous hydrogen to be liquefied, the installation 1 may have a bypass duct provided with an expansion member 15 (valve for example) and connected to the rest of the cycle circuit 16. This means that the cycle circuit 16, after the compression 11 at non-cryogenic temperature may comprise a passage through the supply duct 6 in which the cycle gas is precooled 13 and then purified 25 and then expanded 15 before providing its cooling power to the supply duct 6 and returning to the compression 11 (by giving up its cold energy in the heat exchangers by heating up).

[0063] This means that the compression pressure in the cycle circuit 16 and the pressure in the supply duct 6 can be adjusted to the same level and these streams can be mixed in a part of the supply duct 6 as far as the outlet of the cryogenic purification device 25. Downstream of this cryogenic purification 25, a part of the hydrogen is expanded 36 with a view to the liquefaction while another part is used as high pressure cycle gas.

[0064] As illustrated in [FIG. 3], the supply duct 6 may have a plurality of compressors 10 disposed in series (and/or in parallel), configured to supply the buffer store 9 and/or the cycle circuit 16 with compressed hydrogen.

[0065] For example, the compression may be staged between an initial pressure of the order of atmospheric pressure and a pressure level greater than 60 bar, for example greater than 100 bar, in particular greater than 200 bar, in order to supply the buffer store 9. At the outlet of an intermediate compression stage (target pressure level, for example at 60 bar), the supply duct 6 supplies, for example, the cycle circuit 16 of the refrigerator 8. Downstream of this intermediate compression stage, the bypass duct 19 can compress the hydrogen with at least one additional compressor 10 so as to supply the buffer store 9 at a pressure that can be higher.

[0066] As illustrated schematically in [FIG. 3], the return duct 29 can supply (with expansion 39 if appropriate) the supply duct 6 downstream of the intermediate compression stage. Similarly, there may be provided a duct 139 allowing the buffer store 9 to transfer fluid at the inlet of the intermediate compression stage (or an upstream compression stage), so as to supply the supply duct 6 further upstream at a lower pressure (for example, when the pressure in the buffer store 9 is relatively low).

[0067] The pressure within the buffer store 9 may be variable according to its degree of filling between a determined maximum level (for example 250 bara) and a minimum level and, for example, a pressure level that may be lower than the target pressure of the cycle circuit (final compressor(s) 10 switched off).

[0068] This makes it possible to use the buffer store 9 as far as a relatively low pressure, for example 5 bara. The use of all the pressure of the buffer store 9 makes it possible to reduce its size thereof (typically from 10% to 25% for the same quantity of hydrogen stored).

[0069] Thus, the buffer store 9 can be configured to store the gaseous hydrogen as far as a determined maximum storage pressure (e.g. 250 bar) that is higher than the target pressure (e.g. 60 bar) but the buffer store 9 can be configured to provide gas to the compression portion of the cycle circuit (and/or to the supply duct 6) at the target pressure or at a pressure lower than the target pressure.

[0070] As also illustrated in [FIG. 3], one duct of the cycle circuit may send cycle gas back to the compression (to an intermediate stage with or without a compression 11 if appropriate).

[0071] As illustrated schematically in [FIG. 5], another user 26 of the compressed gaseous hydrogen can be connected branching off from the supply duct 6 (in parallel with the inlet of the liquefier and in parallel with the buffer store 9).

[0072] In addition, an additional duct 161 or loop with a compressor 11 may be provided so as to supply the cycle circuit 16 with hydrogen at the intermediate pressure (60 bar). Similarly, another provision duct 17 can connect the buffer store 9 to the inlet or to the outlet of at least one of the compressor(s) 11 for the cycle gas and may be configured to allow pressurised gaseous hydrogen to be provided to the cycle circuit 16 at a determined pressure level.

[0073] As illustrated schematically in [FIG. 7], the installation 1 may comprise at least one liquid hydrogen store 18 connected to a downstream end of the supply duct 6 leaving the liquefier 7. The store 18 is of the cryogenic type and is configured to collect the hydrogen liquefied by the liquefier 7.

[0074] The installation 1 may comprise filling circuitry 20 connected to the liquid hydrogen store 18 and configured to allow the filling of tank(s) 21, for example mobile tanks (typically delivery trucks). To this end, the installation 1 comprises a set of duct(s) 22, 23, 24 for recovering the vaporization gases generated at the liquid hydrogen store 18 and/or at the filling circuitry 20 (for example so as to recover the vaporization gas from the tanks 21 to be filled). This set of duct(s) 22, 23, 24 for recovering the vaporization gases being connected to the supply circuit 6 so as to recycle, if appropriate, the recovered vaporization gas into the supply duct 6 (if appropriate with a compression 111).

[0075] Thus, vaporization gas at intermediate pressure can be recovered at the start of depressurization of the trucks/ships 21, this vaporization gas can be mixed with the hydrogen of the supply duct 6 with or without intermediate compressor 11 depending on the pressure level.

[0076] As illustrated schematically in [FIG. 6], the installation 1 may have a plurality of liquefiers 7 connected in parallel to the supply duct 6 and also connected in parallel to the buffer store 9.

[0077] The processes described above and below can therefore be applied (simultaneously or not) to all or some of the liquefiers in parallel.

[0078] The invention allows the installation to be adapted to fluctuations in production (intermittent renewable energy for example) with an integration offering maximum synergies.

[0079] While the invention has been described in conjunction with specific embodiments thereof, it is evident that many alternatives, modifications, and variations will be apparent to those skilled in the art in light of the foregoing description. Accordingly, it Is intended to embrace all such alternatives, modifications, and variations as fall within the spirit and broad scope of the appended claims. The present invention may suitably comprise, consist or consist essentially of the elements disclosed and may be practiced in the absence of an element not disclosed. Furthermore, if there is language referring to order, such as first and second, it should be understood in an exemplary sense and not in a limiting sense. For example, it can be recognized by those skilled in the art that certain steps can be combined into a single step.

[0080] The singular forms a, an and the include plural referents, unless the context clearly dictates otherwise.

[0081] Comprising in a claim is an open transitional term which means the subsequently identified claim elements are a nonexclusive listing i.e. anything else may be additionally included and remain within the scope of comprising. Comprising is defined herein as necessarily encompassing the more limited transitional terms consisting essentially of and consisting of; comprising may therefore be replaced by consisting essentially of or consisting of and remain within the expressly defined scope of comprising.

[0082] Providing in a claim is defined to mean furnishing, supplying, making available, or preparing something. The step may be performed by any actor in the absence of express language in the claim to the contrary.

[0083] Optional or optionally means that the subsequently described event or circumstances may or may not occur. The description includes instances where the event or circumstance occurs and instances where it does not occur.

[0084] Ranges may be expressed herein as from about one particular value, and/or to about another particular value. When such a range is expressed, it is to be understood that another embodiment is from the one particular value and/or to the other particular value, along with all combinations within said range.

[0085] All references identified herein are each hereby incorporated by reference into this application in their entireties, as well as for the specific information for which each is cited.