PLANT AND METHOD FOR PROVIDING LIQUID HYDROGEN

Description

[0001] The present invention relates to a liquefied hydrogen supply facility and a liquefied hydrogen supply method.

[0002] Such an installation and such a method are known from US2020 / 149684A1.

[0003] A hydrogen liquefier is generally configured to produce liquid hydrogen without it being possible to guarantee continuous operation. The liquid hydrogen produced by the liquefier is therefore stored in one or more liquefied hydrogen tanks from which refillable tanks such as semi-trailers are filled. Thus, even when the liquefier is stopped, it is still possible to ensure the filling of one or more refillable tanks.

[0004] When filling a tank to be filled, it is necessary to carry out one or more steps of sweeping and / or purging the transfer lines used for the transfer of liquefied hydrogen, from the tank to the tank to be filled. These sweeping and / or purging steps are carried out with pressurized hydrogen gas coming from a high-pressure cycle of the liquefier.

[0005] A problem then arises when the liquefier is stopped, since it becomes impossible to have pressurized hydrogen gas available for flushing and / or purging the transfer lines.

[0006] The present invention aims to effectively remedy these drawbacks by proposing a liquefied hydrogen supply installation comprising: a source of gaseous hydrogen; a liquefier configured to be supplied with gaseous hydrogen by the source and to deliver liquefied hydrogen; a first liquefied hydrogen tank configured to receive liquefied hydrogen from the liquefier, via a first supply line and being configured to store this liquefied hydrogen at a pressure lower than a first predetermined pressure; at least one transfer line configured to allow the transfer of liquefied hydrogen from the first tank to a tank to be filled, the transfer line being connected to the first tank by at least one transfer line; a second liquefied hydrogen tank configured to receive, in particular by gravity, liquefied hydrogen from the first tank, via a second supply line, the second tank being configured to store this liquefied hydrogen;a pressurization system configured to pressurize the second tank to a second predetermined pressure higher than the first predetermined pressure; at least one vaporization line connecting the second tank and / or the pressurization system to the transfer line to allow the transfer of pressurized hydrogen gas from the second tank and / or the pressurization system to the transfer line, for example for the purpose of purging or flushing the transfer line; a vaporization system configured to heat the hydrogen gas circulating in the vaporization line.;

[0007] The invention thus makes it possible to reliably carry out a sweep or purge of equipment in a liquefaction installation such as a transfer line.

[0008] According to one embodiment, the installation comprises a control unit configured to selectively transfer pressurized hydrogen gas from the second tank and / or the pressurization system to the transfer line when the liquefier is stopped, for example for the purpose of purging or flushing the transfer line.

[0009] According to one embodiment, the installation comprises a set of isolation valves configured to fluidly isolate the second tank from the first tank and / or to fluidly isolate the second tank from the transfer line, in particular to allow pressurization of the second tank.

[0010] According to one embodiment, the pressurization system comprises a pressurization line connecting the lower and upper parts of the second tank and comprising an atmospheric heater for converting a portion of the liquefied hydrogen circulating in the pressurization line into gaseous hydrogen.

[0011] According to one embodiment, the first predetermined pressure is equal to 2 bara.

[0012] According to one embodiment, the second predetermined pressure is equal to 5 bara.

[0013] According to one embodiment, the transfer line is configured to allow the transfer of hydrogen vapor from the tank to be filled to the liquefier, the transfer line being connected to the liquefier by at least one vapor collection pipe.

[0014] According to one embodiment, the vaporization line is connected to the liquefier, in particular via a purge line, to allow the transfer of pressurized hydrogen gas from a high-pressure cycle of the liquefier to the transfer line, for example for the purpose of a purge and / or sweeping operation of the transfer line.

[0015] According to one embodiment, the control unit is configured to selectively transfer pressurized hydrogen gas from the liquefier to the transfer line, when the liquefier is in operation, for example for a purging or sweeping operation of the transfer line.

[0016] According to one embodiment, the installation comprises a set of valves, for example for regulation, each valve of the set being mounted in one of the pipes and configured to selectively allow or prevent the passage of the fluid circulating in the pipe in which it is mounted.

[0017] According to one embodiment, the control unit is configured to control the set of valves to allow or prevent the passage of the fluid.

[0018] The invention further relates to a method for supplying liquefied hydrogen by means of an installation as described above, the method comprising the steps: a) transferring liquefied hydrogen from the first tank to the second tank; b) pressurizing the second tank to the second predetermined pressure; c) transferring pressurized hydrogen gas from the second tank and / or the pressurization system to the transfer line, for example for purging or flushing the transfer line.

[0019] According to one embodiment, step b) is carried out prior to step c), step b) being carried out in particular for a predetermined duration configured to allow the pressure in the second tank to reach the second predetermined pressure.

[0020] According to one embodiment, steps a) and / or b) and / or c) are carried out only when the liquefier is stopped.

[0021] According to one embodiment, the method comprises step d) of transferring pressurized hydrogen gas from the liquefier to the transfer line, for example for the purpose of purging and / or sweeping the transfer line.

[0022] According to one embodiment, steps a), b) and c) are carried out successively.

[0023] The invention will be better understood by reading the following description and examining the accompanying figures. These figures are given only for illustrative purposes but in no way limit the invention. Fig. 1 There figure 1 is a schematic representation of an installation according to the invention; Fig. 2 there figure 2 is a schematic representation of a method according to the invention.

[0024] In reference to the figure 1 , a liquefied hydrogen supply installation 1 comprises a liquefier 3 and a source 2 of gaseous hydrogen. The liquefier 3 is configured to be supplied with gaseous hydrogen by the source 2 and to deliver liquefied hydrogen.

[0025] The installation 1 comprises a first tank 4 of liquefied hydrogen configured to receive liquefied hydrogen from the liquefier 3, via a first supply pipe 21 and being configured to store this liquefied hydrogen at a pressure lower than a first predetermined pressure.

[0026] The first predetermined pressure is equal to 2 bara.

[0027] The installation 1 comprises at least one transfer line 7 configured to allow the transfer of liquefied hydrogen from the first tank 4 to a tank to be filled 30, such as a semi-trailer, the transfer line 7 being connected to the first tank 4 by at least one transfer pipe 22.

[0028] The installation 1 comprises a second tank 5 of liquefied hydrogen configured to receive liquefied hydrogen from the first tank 4, via a second supply pipe 23, the second tank 5 being configured to store this liquefied hydrogen.

[0029] The first 4 and second 5 tanks each have two walls separated by insulation.

[0030] The installation 1 comprises a pressurization system 6 configured to allow the second tank 5 to be pressurized to a second predetermined pressure higher than the first predetermined pressure.

[0031] The second predetermined pressure is equal to 5 bara.

[0032] The installation 1 comprises at least one vaporization pipe 28 connecting the second tank 5 and / or the pressurization system 6 to the transfer line 7 to allow the transfer of pressurized hydrogen gas from the second tank 5 and / or the pressurization system 6 to the transfer line 7, for example for the purpose of a purging or sweeping operation of the transfer line 7.

[0033] The installation 1 comprises a vaporization system 8 configured to heat the hydrogen gas circulating in the vaporization line 28.

[0034] The vaporization system 8 is fluidically connected to the pressurization line 26 via a fluid inlet line 25.

[0035] The installation 1 comprises a control unit configured to selectively transfer pressurized hydrogen gas from the second tank 5 and / or from the pressurization system 6, to the transfer line 7, when the liquefier 3 is stopped, for example for the purpose of a purging or sweeping operation of the transfer line 7.

[0036] The installation 1 comprises a set of isolation valves 13, 15 configured to fluidly isolate the second tank 5 from the first tank 4 and / or to fluidly isolate the second tank 5 from the transfer line 7, in particular to allow the pressurization of the second tank 5.

[0037] The pressurization system 6 comprises a pressurization line 24, 26 connecting the lower and upper parts of the second tank 5 and comprising an atmospheric heater 9 for converting a portion of the liquefied hydrogen circulating in the pressurization line 24, 26 into gaseous hydrogen.

[0038] The transfer line 7 is configured to allow the transfer of hydrogen vapor from the tank to be filled 30 to the liquefier 3, the transfer line 7 being connected to the liquefier 3 by at least one vapor collection line 29.

[0039] The vaporization line 28 is connected to the liquefier 3, in particular via a purge line 27, to allow the transfer of pressurized hydrogen gas from a high-pressure cycle of the liquefier 3 to the transfer line 7, for example for the purpose of a purge and / or sweeping operation of the transfer line 7.

[0040] The control unit is configured to selectively transfer pressurized hydrogen gas from the liquefier 3 to the transfer line 7, when the liquefier 3 is in operation, for example for a purging or flushing operation of the transfer line 7.

[0041] The installation comprises a set of valves (11, 12, 13, 14, 15, 16, 17, 18, 19) for example for regulation, each valve (11, 12, 13, 14, 15, 16, 17, 18, 19) of the set being mounted in one of the pipes and configured to selectively allow or prevent the passage of the fluid circulating in the pipe in which it is mounted.

[0042] According to one embodiment, the control unit is configured to control the valve assembly (11, 12, 13, 14, 15, 16, 17, 18, 19) to allow or prevent the passage of fluid in the conduit in which the valve of the valve assembly is mounted.

[0043] There figure 2represents a method for supplying liquefied hydrogen by means of a plant 1 as described above. The method comprises the steps: a) transferring liquefied hydrogen from the first tank 4 to the second tank 5; b) pressurizing the second tank 5 to the second predetermined pressure; c) transferring pressurized hydrogen gas from the second tank 5 and / or the pressurization system 6 to the transfer line 7, for example for purging or flushing the transfer line 7.

[0044] Step b) is carried out before step c).

[0045] Step b) is carried out for a predetermined duration configured to allow the pressure in the second tank 5 to reach the second predetermined pressure.

[0046] Steps a) and / or b) and / or c) are carried out only when the liquefier 3 is stopped. This makes it possible to ensure scavenging and / or purging, for example of the transfer line 7, even when the liquefier 3 is stopped or unavailable, or when it is no longer able to supply liquefied hydrogen.

[0047] The method comprises a step d) of transferring pressurized hydrogen gas from the liquefier 3 to the transfer line 7, for example with a view to a purging and / or scavenging operation of the transfer line 7. This makes it possible, in a nominal operating mode, to ensure scavenging and / or purging, for example of the transfer line 7.

[0048] Steps a), b) and c) are carried out successively, in this order.

[0049] Step a) is carried out as soon as the filling level of the second tank 5 becomes lower than a first predetermined level, for example equal to 30%, preferably equal to 1%. Step b) is carried out when the filling level of the second tank 5 becomes higher than a second predetermined level, for example equal to 30%, preferably equal to 50%. The second predetermined level is higher than the first predetermined level. Step b) is carried out when the pressure in the second tank 5 is lower than the second predetermined pressure.

[0050] The second predetermined pressure is determined to ensure proper flushing and / or purging of the transfer line 7.

[0051] Step b) is performed when a scavenging or purging operation is required and if the pressure in the second tank 5 is lower than the second predetermined pressure. Alternatively, step b) is performed so as to permanently maintain the pressure in the second tank at the second predetermined pressure.

[0052] Step c) is carried out as soon as the filling level of the second tank 5 becomes higher than the second predetermined level.

[0053] Step c) is performed when a scavenging or purging operation is required and if the pressure in the second tank 5 is greater than or equal to the second predetermined pressure.

Claims

1. Installation (1) for supplying liquefied hydrogen, comprising: • a source (2) of gaseous hydrogen; • a liquefier (3) configured to be supplied with gaseous hydrogen by the source (2) and to deliver liquefied hydrogen; • a first tank (4) for liquefied hydrogen configured to receive liquefied hydrogen from the liquefier (3), via a first supply line (21), and being configured to store this liquefied hydrogen at a pressure lower than a first predetermined pressure; • at least one transfer line (7) configured to allow the transfer of liquefied hydrogen from the first tank (4) to a tank to be filled (30), the transfer line (7) being connected to the first tank (4) by at least one transfer line (22); • a second tank (5) for liquefied hydrogen configured to receive, notably by gravity, liquefied hydrogen from the first tank (4), via a second supply line (23), the second tank (5) being configured to store this liquefied hydrogen; • a pressurization system (6) configured to allow the pressurization of the second tank (5) to a second predetermined pressure higher than the first predetermined pressure; • at least one vaporization line (28) connecting the second tank (5) and / or the pressurization system (6) to the transfer line (7) to allow the transfer of pressurized gaseous hydrogen from the second tank (5) and / or the pressurization system (6) to the transfer line (7), for example for a purge or sweep operation of the transfer line (7); • a vaporization system (8) configured to heat the gaseous hydrogen circulating in the vaporization line (28).

2. Installation (1) according to the preceding claim, comprising a control unit configured to selectively transfer pressurized gaseous hydrogen from the second tank (5) and / or the pressurization system (6) to the transfer line (7), when the liquefier (3) is stopped, for example for a purge or sweep operation of the transfer line (7).

3. Installation (1) according to one of the preceding claims, comprising a set of isolation valves (13, 15) configured to fluidically isolate the second tank (5) from the first tank (4) and / or to fluidically isolate the second tank (5) from the transfer line (7), notably to allow the pressurization of the second tank (5).

4. Installation (1) according to one of the preceding claims, the pressurization system (6) comprising a pressurization line (24, 26) connecting the lower and upper parts of the second tank (5) and comprising an atmospheric heater (9) to convert a part of the liquefied hydrogen circulating in the pressurization line (24, 26) into gaseous hydrogen.

5. Installation (1) according to one of the preceding claims, the transfer line (7) being configured to allow the transfer of hydrogen vapor from the tank to be filled (30) to the liquefier (3), the transfer line (7) being connected to the liquefier (3) by at least one vapor collection line (29).

6. Installation (1) according to one of the preceding claims, the vaporization line (28) being also connected to the liquefier (3), notably via a purge line (27), to allow the transfer of pressurized gaseous hydrogen from a high-pressure cycle of the liquefier (3) to the transfer line (7), for example for a purge and / or sweep operation of the transfer line (7).

7. Method for supplying liquefied hydrogen by means of an installation (1) according to one of the preceding claims, comprising the steps of: • a) transferring liquefied hydrogen from the first tank (4) to the second tank (5); • b) pressurizing the second tank (5) to the second predetermined pressure; • c) transferring pressurized gaseous hydrogen from the second tank (5) and / or the pressurization system (6) to the transfer line (7), for example for a purge or sweep operation of the transfer line (7).

8. Method according to the preceding claim, step b) being carried out prior to step c), step b) being notably carried out for a predetermined duration configured to allow the pressure in the second tank (5) to reach the second predetermined pressure.

9. Method according to one of claims 7 to 8, steps a) and / or b) and / or c) being carried out only when the liquefier (3) is stopped.

10. Method according to one of claims 7 to 9, comprising step d) of transferring pressurized gaseous hydrogen from the liquefier (3) to the transfer line (7), for example for a purge and / or sweep operation of the transfer line (7).