Method for filling a tank with liquefied gas

Abstract

To provide a method for filling a tank for at least partially cooling a transfer circuit before transferring liquid gas from a liquid gas supply source to a liquid gas tank.SOLUTION: In a method for filling a tank with pressurized liquid gas from a liquid gas supply source, a transfer circuit includes a third transfer pipe 5 and a fourth transfer pipe 7 respectively connected to a first transfer pipe 3 and a second transfer pipe 6. The circuit includes sets of valves 36, 46, 13, 33, 15, 17 for controlling flow of liquid in the pipes of the circuit, reduces the pressure of the liquid gas tank before transferring the liquid gas from the liquid gas supply source 4 to the liquid gas tank, cools at least a portion of the transfer circuit, and transfers pressurized vaporization gas included in the liquid gas tank through a second end part 26 of the second pipe, the third transfer pipe, the first transfer pipe, the fourth transfer pipe, and a first end part 16 of the second transfer pipe for gas transfer.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a method for filling a tank with liquefied gas.

[0002] More specifically, the present invention relates to a first pipe for liquid transfer having a first end connected to a liquefied gas source and a second end connected to a liquefied gas tank, and a first end connected to a gas recovery member. A filling method for filling the above tank with pressurized liquefied gas from a liquefied gas source, using a filling device having a transfer circuit provided with a second pipe for gas transfer having a second end connected to the tank to be filled. The transfer circuit includes a third transfer pipe and a fourth transfer pipe each connected to the first transfer pipe and the second transfer pipe, and the transfer circuit includes a set of valves for controlling the flow of fluid in the pipes of the transfer circuit. The method includes depressurizing the liquefied gas tank and cooling at least a part of the transfer circuit before transferring liquefied gas from the liquefied gas source to the liquefied gas tank.

Background Art

[0003] Before a series of operations for filling a tank with liquefied gas, the transfer circuit (such as the flexible pipes of the tank to be filled) is generally at room temperature. In this case, it is necessary to cool the entire mechanism to the temperature of the liquefied gas (i.e., 21.7 K in the case of liquid hydrogen) before filling.

[0004] Currently, cooling is performed by the flow of liquid hydrogen from a storage supply source. As a result, liquid hydrogen vaporizes during the cooling of the liquid transfer pipe. Depending on the equipment, 5 to 15 kg of liquid hydrogen evaporates, and the duration of the operation can vary from 5 to 10 minutes.

[0005] This cooling wastes time and causes loss of the cryogenic properties of the fluid produced by the liquefier that fills the supply source.

[0006] Low-temperature molecules under reduced pressure are generally recovered by passing through a heater and then a cyclone compressor. Frigori is not utilized because it is costly from an energy standpoint.

[0007] The energy required to liquefy air gas is far less than that required for hydrogen. Therefore, gas return is not utilized, and molecules are not always recovered.

[0008] In the case of liquid helium facilities, molecular recovery is generally performed. Frigoli recovery can be incorporated into the liquefaction system. Depending on the gas return temperature, cold helium is injected directly at different stages of the liquefaction. [Overview of the project]

[0009] One objective of the present invention is to overcome all or part of the aforementioned drawbacks of the prior art.

[0010] For this purpose, the method according to the present invention, and moreover, according to the general definitions given in the above preface, is characterized in that the depressurization of the liquefied gas tank and the cooling of the transfer circuit are characterized in that the transfer of pressurized vaporized gas contained in the liquefied gas tank is carried out via a second end of a second pipe for gas transfer, a third transfer pipe, a first transfer pipe, a fourth transfer pipe, and a first end of the second transfer pipe.

[0011] Therefore, the depressurized cold gas is flowed into the liquid transfer line to be cooled.

[0012] Therefore, this method allows the cooling gas from the tank to be filled to be utilized (for example, before this gas passes through the heater).

[0013] Furthermore, embodiments of the present invention may include one or more of the following features: - The pressurized vaporized gas transferred from the liquefied gas tank to the first end of the second transfer pipe is reheated and released, and / or compressed and / or stored in a gas recovery member. - The third or fourth transfer pipe is located at two ends of the transfer circuit, namely the second end of the first and second transfer pipes and the first end of the first and second transfer pipes, respectively. -The third and fourth transfer pipes each have their own set of valves. - The liquefied gas tank has a pressure between 1.2 and 10 bar, for example between 1.4 and 7 bar, before depressurization, and after depressurization, the pressure becomes between 1.1 and 1.4 bar. -This method comprises the steps of depressurizing the liquefied gas tank and cooling at least a portion of the transfer circuit, after which the liquefied gas is transferred from the supply source to the liquefied gas tank via a first transfer pipe. - The liquefied gas is hydrogen or helium.

[0014] The present invention may also be any alternative device or method having any combination of the above or below features within the context of the claims.

[0015] Further unique features and advantages will become clear when you read the following explanation, which is given in reference to the diagram. [Brief explanation of the drawing]

[0016] [Figure 1] A schematic diagram illustrating an example of the configuration, operation, and method of the filling apparatus according to the present invention is shown. [Modes for carrying out the invention]

[0017] The apparatus includes a fluid circuit comprising a first pipe 3 for liquid transfer, which has a first end (for example, located to the left of valve 13 in the schematic diagram) intended to be connected to a liquefied gas supply source 4 (particularly to the liquid phase of the supply tank), and a second end (for example, located to the right or left of valve 23 in the schematic diagram) intended to be connected to a tank 2 to be filled (particularly to its liquid phase).

[0018] The supply source 4 typically comprises a storage section for liquefied gas with the gas phase on top. The supply source is pressurized or can be pressurized, and this pressure can be the force to transfer the fluid. A transfer pump can also be envisaged.

[0019] The fluid circuit comprises a second pipe 6 for gas transfer, having a first end 16 intended to be connected (e.g., to its gas phase) to the liquefied gas supply source 4 or to the gas recovery member 8, and a second end intended to be connected (e.g., to its gas phase) to the tank 2 to be filled.

[0020] The fluid circuit comprises a third transfer pipe 5 that connects the first transfer pipe 3 and the second transfer pipe 6 and is provided with a valve 15.

[0021] The fluid circuit comprises a fourth transfer pipe 7 that connects the first transfer pipe 3 and the second transfer pipe 6 and is provided with a valve 17.

[0022] The third transfer pipe 5 and the fourth transfer pipe 7 are preferably located at two ends of the fluid circuit (respectively, towards the tank 2 to be filled and towards the supply source 4).

[0023] For example, without limitation, the third pipe 5 can be part of the fluid circuit integrated with the tank 2 and is provided with a fluid connection such as a removable connector or a quick connector, and can be configured to be connected to the pipes forming the first pipe 3 and the second pipe (e.g., on the right side of the flexible part symbolically shown by the wavy line).

[0024] The fluid circuit comprises a set of valves for controlling the flow of fluid in the pipes of the fluid circuit. For example, the first pipe 3 for liquid transfer comprises at least one equipment and / or a fluid control valve 33.

[0025] Similarly, the second transfer pipe 6 comprises at least one equipment and / or fluid control valves 36, 46.

[0026] This architecture enables the filling of the tank 2 in a single flow (only the first liquid pipe 3) or in a multi-flow (the first pipe 3 for transferring the liquid and the second pipe 6 for discharging the gas in the opposite direction).

[0027] The third transfer pipe 5 and the fourth transfer pipe 7 each preferably comprise at least one piece of equipment and / or fluid control valves 15, 17.

[0028] Before transferring the liquefied gas from the source 4 to the liquefied gas tank 2, it is necessary to perform the depressurization of the liquefied gas tank 2 and the cooling of at least part of the transfer circuit.

[0029] At least part of the depressurization of the liquefied gas tank 2 and the cooling of the transfer circuit are performed by the transfer of the pressurized vaporized gas contained in the liquefied gas tank 2 via the second end 26 of the second pipe 6 for gas transfer, the third transfer pipe 5, the first transfer pipe 3, the fourth transfer pipe 7, and the first end 16 of the second pipe 6.

[0030] That is, the flow of the low-temperature depressurized gas is passed through at least part of the first liquid pipe 3 via the bypass formed by the third transfer pipe 5 and the fourth transfer pipe 7. This can be achieved by appropriate valve control (for example, during this depressurization, valves 15, 33, 17, and 56 are opened and other valves are closed).

[0031] Therefore, this cooling of the transfer circuit is carried out during the evaporation of the liquefied gas at the start of filling and during depressurization (effect). When hydrogen is applied, this process enables the reduction of the evaporation of hydrogen (H2) from 0.02 kg to 0.08 kg depending on the equipment.

[0032] Thereby, by cooling the liquid line 3 during the depressurization step, the gas return of the tank 2 to be filled can be utilized.

[0033] This solution has several advantages.

[0034] Therefore, this method allows for savings from an energy balance perspective (there is no liquid flushing from source 4 or the liquefaction unit).

[0035] This solution allows for saving 4 to 14 kg of liquid hydrogen through cooling (in each fill), depending on the equipment.

[0036] Furthermore, this solution saves time in the series of operations required to fill tank 2 with hydrogen without any loss of material (5 to 10 minutes depending on the equipment).

[0037] As illustrated, the transfer circuit may have several transverse pipes connecting a first pipe 3 to a second pipe 6, particularly toward a tank 2 to be filled. For example, two transverse pipes may be provided at the second end, each with a valve. These two transverse pipes may be firmly connected to the tank 2. Furthermore, two valves 33, 46 may be provided between these two transverse pipes, on the first and second transfer pipes, respectively.

[0038] The flow of vaporized gas from tank 2 to be filled can be carried through one or more of these transverse pipes by appropriate openings of a set of valves. The following is a direct reproduction of the claims as originally filed. [1] A method for filling a liquefied gas tank (2) with pressurized liquefied gas from a liquefied gas supply source (4) using a filling device, wherein the filling device includes a transfer circuit comprising a first transfer pipe (3) for liquid transfer having a first end (13) connected to the liquefied gas supply source (4) and a second end (23) connected to the liquefied gas tank (2), and a second transfer pipe (6) for gas transfer having a first end (16) connected to a gas recovery member (8) and a second end connected to the liquefied gas tank (2), The transfer circuit comprises a third transfer pipe (5) and a fourth transfer pipe (7), the third transfer pipe (5) and the fourth transfer pipe (7) being connected to the first transfer pipe (3) and the second transfer pipe (6), respectively, and the transfer circuit comprises a set of valves (36, 46, 13, 33, 15, 17) for controlling the fluid flow in the transfer pipes of the transfer circuit, wherein the method comprises depressurizing the liquefied gas tank (2) and cooling at least a portion of the transfer circuit before transferring liquefied gas from the liquefied gas supply source (4) to the liquefied gas tank (2), A method characterized in that reducing the pressure of the liquefied gas tank (2) and cooling the transfer circuit includes transferring the pressurized vaporized gas contained in the liquefied gas tank (2) through the second end of the second transfer pipe (6) for gas transfer, the third transfer pipe (5), the first transfer pipe (3), the fourth transfer pipe (7), and the first end (16) of the second transfer pipe (6). [2] The method according to [1], characterized in that the pressurized vaporized gas transferred from the liquefied gas tank (2) to the first end (16) of the second transfer pipe (6) is reheated and released, and / or compressed, and / or stored in the gas recovery member (8). [3] The method according to [1] or [2], characterized in that the third transport pipe (5) or the fourth transport pipe (7) is located at two ends of the transport circuit, namely the second end of the first transport pipe (3) and the second transport pipe (6) and the first end of the first transport pipe (3) and the second transport pipe (6), respectively. [4] The method according to any one of [1] to [3], characterized in that the third transfer pipe (5) and the fourth transfer pipe (7) each comprise their respective sets of valves (15, 17). [5] The method according to any one of [1] to [4], characterized in that the liquefied gas tank (2) has a pressure between 1.2 and 10 bar, for example between 1.4 and 7 bar, before depressurization, and a pressure between 1.1 and 1.4 bar after depressurization. [6] The method according to any one of [1] to [5], characterized in that the method comprises the step of depressurizing the liquefied gas tank (2), cooling at least a portion of the transfer circuit, and then transferring the liquefied gas from the liquefied gas supply source (4) to the liquefied gas tank (2) via the first transfer pipe (3). [7] The method according to any one of [1] to [6], characterized in that the liquefied gas is hydrogen or helium.

Claims

1. A method for filling a liquefied gas tank (2) with pressurized liquefied gas from a liquefied gas supply source (4) using a filling device, wherein the filling device includes a transfer circuit comprising a first transfer pipe (3) for liquid transfer having a first end (13) connected to the liquefied gas supply source (4) and a second end (23) connected to the liquefied gas tank (2), and a second transfer pipe (6) for gas transfer having a first end (16) connected to a gas recovery member (8) and a second end connected to the liquefied gas tank (2), The transfer circuit comprises a third transfer pipe (5) and a fourth transfer pipe (7), the third transfer pipe (5) and the fourth transfer pipe (7) being connected to the first transfer pipe (3) and the second transfer pipe (6), respectively, the transfer circuit comprises a set of valves (36, 46, 13, 33, 15, 17) for controlling the fluid flow in the transfer pipes of the transfer circuit, the method comprising depressurizing the liquefied gas tank (2) and cooling at least a portion of the transfer circuit before transferring the liquefied gas from the liquefied gas supply source (4) to the liquefied gas tank (2), A method comprising reducing the pressure of the liquefied gas tank (2) and cooling the transfer circuit, which includes transferring the pressurized vaporized gas contained in the liquefied gas tank (2) via the second end of the second transfer pipe (6) for gas transfer, the third transfer pipe (5), the first transfer pipe (3), the fourth transfer pipe (7), and the first end (16) of the second transfer pipe (6), wherein the third transfer pipe (5) and the fourth transfer pipe (7) are located at two ends of the transfer circuit, namely the second end of the first transfer pipe (3) and the second transfer pipe (6), and the first end of the first transfer pipe (3) and the second transfer pipe (6), respectively.

2. The method according to claim 1, characterized in that the pressurized vaporized gas transferred from the liquefied gas tank (2) to the first end (16) of the second transfer pipe (6) is reheated and released, and / or compressed, and / or stored in the gas recovery member (8).

3. The method according to claim 1 or 2, characterized in that the third transfer pipe (5) and the fourth transfer pipe (7) each comprise their respective sets of valves (15, 17).

4. The method according to any one of claims 1 to 3, characterized in that the liquefied gas tank (2) has a pressure between 1.2 and 10 bar before depressurization, and a pressure between 1.1 and 1.4 bar after depressurization.

5. The method according to any one of claims 1 to 4, characterized in that the method comprises the step of depressurizing the liquefied gas tank (2), cooling at least a portion of the transfer circuit, and then transferring the liquefied gas from the liquefied gas supply source (4) to the liquefied gas tank (2) via the first transfer pipe (3).

6. The method according to any one of claims 1 to 5, characterized in that the liquefied gas is hydrogen or helium.

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