Liquefied gas facility and ship

Abstract

This liquefied gas facility comprises: a tank that stores a liquefied gas; a first supply flow passage for supplying a gas generated by vaporization of the liquefied gas from the tank to a supply destination; a second supply flow passage for supplying the gas from the tank to a supply destination different from the supply destination of the first supply flow passage; a first apparatus that is disposed in the first supply flow passage and adjusts the pressure or the temperature of the gas; a second apparatus that is the same type as the first device, is disposed in the second supply flow passage, and adjusts the pressure or temperature of the gas; a first bypass flow passage that connects a first connection part positioned upstream of the first apparatus in the first supply flow passage and a second connection part positioned upstream of the second apparatus in the second supply flow passage; and a second bypass flow passage that connects a third connection part positioned downstream of the first apparatus in the first supply flow passage and a fourth connection part positioned downstream of the second apparatus in the second supply flow passage.

Description

Liquefied gas equipment and ship

[0001] The present disclosure relates to liquefied gas equipment and a ship.

[0002] Patent Document 1 describes an evaporative gas reliquefaction system including a first compressor and a second compressor that is a redundancy compressor installed in preparation for a failure of the first compressor. The first compressor is installed on an evaporative gas supply line, and compresses evaporative gas supplied to a fuel demand destination along the evaporative gas supply line. The second compressor is installed on a redundancy line that branches from the evaporative gas supply line upstream of the first compressor and connects to the evaporative gas supply line downstream of the first compressor, and compresses evaporative gas supplied to a fuel demand destination along the redundancy line.

[0003] International Publication No. 2016-195237

[0004] In the evaporative gas reliquefaction system of Patent Document 1, since the second compressor is installed to ensure redundancy, there is room for improvement in the system cost.

[0005] An object of the present disclosure is to provide redundancy to liquefied gas equipment while suppressing an increase in cost.

[0006] One aspect of the present disclosure provides a liquefied gas equipment including: a tank that stores liquefied gas; a first supply flow path for supplying gas generated by vaporization of the liquefied gas from the tank to a supply destination; a second supply flow path for supplying the gas from the tank to a supply destination different from the supply destination of the first supply flow path; a first device arranged in the first supply flow path that adjusts the pressure or temperature of the gas; a second device of the same type as the first device arranged in the second supply flow path that adjusts the pressure or temperature of the gas; a first bypass flow path that connects a first connection portion located upstream of the first device in the first supply flow path and a second connection portion located upstream of the second device in the second supply flow path; and a second bypass flow path that connects a third connection portion located downstream of the first device in the first supply flow path and a fourth connection portion located downstream of the second device in the second supply flow path.

[0007] In this specification, the "type" of equipment refers to a group of equipment classified by its function. For example, a compressor, which is equipment that adjusts the pressure of a gas, and a heat exchanger, which is equipment that adjusts the temperature of a gas, are different types of equipment. On the other hand, two compressors with different structures are the same type of equipment insofar as they share the common function of adjusting the pressure of a gas. Similarly, two heat exchangers with different structures are the same type of equipment insofar as they share the common function of adjusting the temperature of a gas.

[0008] This configuration allows for redundancy in the liquefied gas equipment while suppressing cost increases. The upstream connections of the first and second equipment, respectively, located in the first and second supply channels, are connected to each other by the first bypass channel, and the downstream connections of the first and second equipment are connected to each other by the second bypass channel. As a result, the first and second equipment of the same type, located in the first and second supply channels that supply gas to different destinations, can back up each other. Consequently, compared to a configuration in which separate equipment is installed in each of the first and second bypass channels to ensure redundancy, this configuration allows for redundancy in the liquefied gas equipment while suppressing costs.

[0009] According to this disclosure, it is possible to provide redundancy to liquefied gas facilities while suppressing cost increases.

[0010] Figure 1 is a schematic diagram showing the configuration of a liquefied gas equipment according to one embodiment of the present disclosure. Figure 2 is a diagram illustrating the flow of hydrogen gas in the liquefied gas equipment when hydrogen gas is supplied from the tank shown in Figure 1 to the combustion device. Figure 3 is a diagram illustrating the flow of hydrogen gas in the liquefied gas equipment when hydrogen gas is supplied from the tank shown in Figure 1 to the combustion device, and in Figure 3, a state in which an abnormality has occurred in the second heat exchanger. Figure 4 is a diagram illustrating the flow of hydrogen gas in the liquefied gas equipment when warming up the tank shown in Figure 1. Figure 5 is a diagram illustrating the flow of hydrogen gas in the liquefied gas equipment when warming up the tank shown in Figure 1, and in Figure 5, a state in which an abnormality has occurred in the second heat exchanger. This is a schematic diagram showing the configuration of a liquefied gas equipment according to a modified embodiment of the embodiment shown in Figure 1.

[0011] Hereinafter, a liquefied gas facility and a vessel according to one embodiment of this disclosure will be described with reference to the attached drawings.

[0012] Figure 1 is a schematic diagram showing the configuration of a liquefied gas equipment 1 according to one embodiment of the present disclosure. The liquefied gas equipment 1 according to this embodiment is installed on a vessel such as a liquefied hydrogen carrier that transports liquefied hydrogen. The liquefied hydrogen in this embodiment is an example of the liquefied gas according to the present disclosure.

[0013] The liquefied gas equipment 1 comprises a tank 10, a first supply channel 20, and a second supply channel 30. In this embodiment, the first supply channel 20 and the second supply channel 30 supply hydrogen gas to different destinations. Specifically, the first supply channel 20 supplies hydrogen gas to a combustion device 40, and the second supply channel 30 supplies hydrogen gas to the tank 10. In the following description, the upstream of the hydrogen gas flow in each of the first and second supply channels 20 and 30 may be simply referred to as "upstream," and the downstream of the hydrogen gas flow in each channel may be simply referred to as "downstream."

[0014] Tank 10 is a cargo tank for storing liquefied hydrogen as cargo. Inside Tank 10 are liquefied hydrogen and hydrogen gas generated by the vaporization of liquefied hydrogen. Specifically, inside Tank 10 is boil-off gas generated when the liquefied hydrogen inside Tank 10 vaporizes due to natural heat input from the outside. In this specification, "hydrogen gas" includes boil-off gas generated by the vaporization of liquefied hydrogen due to natural heat input and hydrogen gas generated when liquefied hydrogen is vaporized by a vaporizer.

[0015] The first supply channel 20 is a channel for supplying hydrogen gas to a combustion device 40 that burns hydrogen gas. One end of the first supply channel 20 is fluidically connected to the internal space of the tank 10, and the other end of the first supply channel 20 is fluidically connected to the combustion device 40. The first supply channel 20 is composed of multiple pipes.

[0016] The combustion device 40 is, for example, a boiler. The combustion device 40 is used to burn hydrogen gas, particularly boil-off gas, taken out from the tank 10. When the pressure inside the tank 10 rises due to heat input to the tank 10, it is necessary to process a portion of the hydrogen gas inside the tank 10 so that the pressure inside the tank 10 does not exceed the allowable pressure of the tank 10. In such cases, the combustion device 40 processes a portion of the hydrogen gas inside the tank 10 by burning it, thereby keeping the pressure inside the tank 10 below the allowable pressure of the tank 10 without releasing the hydrogen gas into the atmosphere.

[0017] The liquefied gas equipment 1 comprises a first compressor 50, a first heat exchanger 60, and a second heat exchanger 61. The first compressor 50, the first heat exchanger 60, and the second heat exchanger 61 are arranged on the first supply channel 20.

[0018] The first compressor 50 is a device that adjusts the pressure of the hydrogen gas flowing through the first supply channel 20. Specifically, the first compressor 50 compresses and increases the pressure of the hydrogen gas flowing through the first supply channel 20. In order to burn hydrogen gas using the combustion device 40 of this embodiment, the pressure of the hydrogen gas supplied to the combustion device 40 must be above a predetermined pressure. The first compressor 50 increases the pressure of the hydrogen gas flowing through the first supply channel 20 so that the pressure of the hydrogen gas supplied to the combustion device 40 becomes higher than the predetermined pressure. The first compressor 50 of this embodiment is an example of the third device according to the present disclosure.

[0019] The first heat exchanger 60 is a device that adjusts the temperature of the hydrogen gas flowing through the first supply channel 20. Specifically, the first heat exchanger 60 is a heater that heats and raises the temperature of the hydrogen gas flowing through the first supply channel 20. The first heat exchanger 60 is located downstream of the first compressor 50 in the first supply channel 20. In order to burn hydrogen gas using the combustion device 40 of this embodiment, the temperature of the hydrogen gas supplied to the combustion device 40 must be above a predetermined temperature. The first heat exchanger 60 raises the temperature of the hydrogen gas flowing through the first supply channel 20 so that the temperature of the hydrogen gas supplied to the combustion device 40 is higher than the predetermined temperature. In other words, the first heat exchanger 60 functions as an afterheater that heats the hydrogen gas discharged from the first compressor 50 to a temperature suitable for combustion of hydrogen gas in the combustion device 40. The amount of heat exchanged by the first heat exchanger 60, i.e., the amount of heating, is variable.

[0020] The second heat exchanger 61 is a device that adjusts the temperature of the hydrogen gas flowing through the first supply channel 20. Specifically, the second heat exchanger 61 is a heater that heats and raises the temperature of the hydrogen gas flowing through the first supply channel 20. The second heat exchanger 61 is located upstream of the first compressor 50 in the first supply channel 20. The second heat exchanger 61 raises the temperature of the hydrogen gas flowing through the first supply channel 20 so that the temperature of the hydrogen gas supplied to the first compressor 50 is higher than the operating intake temperature of the first compressor 50. The second heat exchanger 61 functions as a preheater that heats the hydrogen gas drawn into the first compressor 50 to a temperature suitable for the operation of the first compressor 50. The amount of heat exchange, i.e., the amount of heating, of the second heat exchanger 61 is variable. The second heat exchanger 61 in this embodiment is an example of the first device according to the present disclosure.

[0021] The liquefied gas equipment 1 includes first valves 70A to 70C arranged on the first supply channel 20. In the following description, when there is no need to distinguish between the first valves 70A to 70C, one of the first valves 70A to 70C may simply be referred to as the first valve 70. The first valve 70 is a flow control valve that can adjust the flow rate by changing its opening. The first valve 70 may be able to adjust the flow rate continuously or in steps.

[0022] The first valve 70A is located upstream of the first compressor 50. Specifically, the first valve 70A is located upstream of the first compressor 50 and downstream of the second heat exchanger 61. By adjusting the flow rate through the first valve 70A, the flow rate of hydrogen gas supplied to the first compressor 50 is adjusted.

[0023] The first valve 70B is located upstream of the first heat exchanger 60. Specifically, the first valve 70B is located downstream of the first compressor 50 and upstream of the first heat exchanger 60. By adjusting the flow rate through the first valve 70B, the flow rate of hydrogen gas supplied to the first heat exchanger 60 is adjusted.

[0024] The first valve 70C is located upstream of the second heat exchanger 61. Specifically, the first valve 70C is located downstream of the tank 10 and upstream of the second heat exchanger 61. By adjusting the flow rate through the first valve 70C, the flow rate of hydrogen gas supplied to the second heat exchanger 61 is adjusted.

[0025] The second supply channel 30 is a channel for returning hydrogen gas extracted from tank 10 to tank 10. Both ends of the second supply channel 30 are fluidly connected to the internal space of tank 10. The second supply channel 30 includes a plurality of pipes.

[0026] The second supply channel 30 is used to warm up the tank 10. Warming up the tank 10 is performed to raise the temperature inside the tank 10 to a target temperature using hydrogen gas inside the tank 10 for inspection or repair of the liquefied gas equipment 1.

[0027] The liquefied gas equipment 1 comprises a second compressor 51, a third heat exchanger 62, and a fourth heat exchanger 63. The second compressor 51, the third heat exchanger 62, and the fourth heat exchanger 63 are arranged on the second supply channel 30.

[0028] The second compressor 51 is a device that adjusts the pressure of the hydrogen gas flowing through the second supply channel 30. Specifically, the second compressor 51 increases the pressure of the hydrogen gas flowing through the second supply channel 30 and sends it toward the tank 10. In other words, the second compressor 51 pressurizes the hydrogen gas in the second supply channel 30 toward the tank 10. The second compressor 51 in this embodiment is an example of the fourth device according to the present disclosure.

[0029] The third heat exchanger 62 is a heat exchanger that adjusts the temperature of the hydrogen gas flowing through the second supply channel 30. Specifically, the third heat exchanger 62 is a heater that heats the hydrogen gas flowing through the second supply channel 30 to raise its temperature. The third heat exchanger 62 is located downstream of the second compressor 51 in the second supply channel 30. The third heat exchanger 62 raises the temperature of the hydrogen gas flowing through the second supply channel 30 in order to warm up the tank 10. The third heat exchanger 62 functions as an afterheater that heats the hydrogen gas discharged from the second compressor 51 to a temperature suitable for warming up the tank 10. The amount of heat exchanged by the third heat exchanger 62, i.e., the amount of heating, is variable.

[0030] The fourth heat exchanger 63 is a heat exchanger that adjusts the temperature of the hydrogen gas flowing through the second supply channel 30. Specifically, the fourth heat exchanger 63 is a heater that heats and raises the temperature of the hydrogen gas flowing through the second supply channel 30. The fourth heat exchanger 63 is located upstream of the second compressor 51 in the second supply channel 30. The fourth heat exchanger 63 raises the temperature of the hydrogen gas flowing through the second supply channel 30 so that the temperature of the hydrogen gas supplied to the second compressor 51 is higher than the operating suction temperature of the second compressor 51. The fourth heat exchanger 63 functions as a preheater that heats the hydrogen gas drawn into the second compressor 51 to a temperature suitable for the operation of the second compressor 51. The amount of heat exchanged by the fourth heat exchanger 63, i.e., the amount of heating, is variable.

[0031] The liquefied gas equipment 1 includes second valves 71A to 71C located on the second supply channel 30. In the following description, when there is no need to distinguish between the second valves 71A to 71C, one of the second valves 71A to 71C may simply be referred to as the second valve 71. The second valve 71 is a flow control valve that can adjust the flow rate by changing its opening. The second valve 71 may be able to adjust the flow rate continuously or in steps.

[0032] The second valve 71A is located upstream of the second compressor 51. Specifically, the second valve 71A is located upstream of the second compressor 51 and downstream of the fourth heat exchanger 63. By adjusting the flow rate through the second valve 71A, the flow rate of hydrogen gas supplied to the second compressor 51 is adjusted.

[0033] The second valve 71B is located upstream of the third heat exchanger 62. Specifically, the second valve 71B is located downstream of the second compressor 51 and upstream of the third heat exchanger 62. By adjusting the flow rate through the second valve 71B, the flow rate of hydrogen gas supplied to the third heat exchanger 62 is adjusted.

[0034] The second valve 71C is located upstream of the fourth heat exchanger 63. Specifically, the second valve 71C is located downstream of the tank 10 and upstream of the fourth heat exchanger 63. By adjusting the flow rate through the second valve 71C, the flow rate of hydrogen gas supplied to the fourth heat exchanger 63 is adjusted.

[0035] The liquefied gas equipment 1 includes four bypass channels 80A to 80D that fluidly connect the first supply channel 20 and the second supply channel 30, and four third valves 72A to 72D that correspond one-to-one with the four bypass channels 80A to 80D. In the following description, when there is no need to distinguish between the four bypass channels 80A to 80D, one of the four bypass channels 80A to 80D may simply be referred to as bypass channel 80. Similarly, when there is no need to distinguish between the four third valves 72A to 72D, one of the four third valves 72A to 72D may simply be referred to as third valve 72.

[0036] The bypass channel 80A fluidically connects a connection 21 located upstream of the second heat exchanger 61 in the first supply channel 20 and a connection 31 located upstream of the fourth heat exchanger 63 in the second supply channel 30. Specifically, the connection 21 is located upstream of the first valve 70C and downstream of the tank 10 in the first supply channel 20, and the connection 31 is located upstream of the second valve 71C and downstream of the tank 10 in the second supply channel 30. The bypass channel 80A in this embodiment is an example of the first bypass channel according to the disclosure. The connection 21 according to this embodiment is an example of the first connection according to the disclosure, and the connection 31 according to this embodiment is an example of the second connection according to the disclosure.

[0037] The bypass channel 80B fluidly connects a connection portion 22 located downstream of the first heat exchanger 60 in the first supply channel 20 and a connection portion 32 located downstream of the third heat exchanger 62 in the second supply channel 30. The bypass channel 80B according to this embodiment is an example of the second bypass channel according to the disclosure. The connection portion 22 according to this embodiment is an example of the third connection portion according to the disclosure, and the connection portion 32 according to this embodiment is an example of the fourth connection portion according to the disclosure.

[0038] The bypass flow path 80C fluidly connects a connection portion 23 located downstream of the second heat exchanger 61 and upstream of the first compressor 50 in the first supply flow path 20, and a connection portion 33 located downstream of the fourth heat exchanger 63 and upstream of the second compressor 51 in the second supply flow path 30. Specifically, the connection portion 23 is located upstream of the first valve 70A and downstream of the second heat exchanger 61 in the first supply flow path 20, and the connection portion 33 is located upstream of the second valve 71A and downstream of the fourth heat exchanger 63 in the second supply flow path 30. The bypass flow path 80C according to this embodiment is an example of the third bypass flow path according to this disclosure. The connection portion 23 according to this embodiment is an example of the fifth connection portion according to this disclosure, and the connection portion 33 according to this embodiment is an example of the sixth connection portion according to this disclosure.

[0039] The bypass flow path 80D fluidly connects a connection 24 located downstream of the first compressor 50 and upstream of the first heat exchanger 60 in the first supply flow path 20, and a connection 34 located downstream of the second compressor 51 and upstream of the third heat exchanger 62 in the second supply flow path 30. Specifically, the connection 24 is located upstream of the first valve 70B and downstream of the first compressor 50 in the first supply flow path 20, and the connection 34 is located upstream of the second valve 71B and downstream of the second compressor 51 in the second supply flow path 30.

[0040] The third valves 72 are positioned on their respective bypass passages 80. The third valves 72 are normally closed valves. Except when necessary, the third valves 72 block the flow of hydrogen gas in the corresponding bypass passages 80.

[0041] The first and second compressors 50 and 51 in this embodiment are of the same type of equipment. The first to fourth heat exchangers 60 to 63 in this embodiment are of the same type of equipment. As described above, in this specification, "type" means a group of equipment separated by function. The first and second compressors 50 and 51, which have the function of compressing and increasing the pressure of hydrogen gas, and the first to fourth heat exchangers 60 to 63, which have the function of heating and increasing the temperature of gas, belong to different types. On the other hand, even if the first and second compressors 50 and 51 have different structures, they are of the same type of equipment insofar as they share the common function of adjusting the pressure of hydrogen gas. Also, even if the first to fourth heat exchangers 60 to 63 have different structures, they are of the same type of equipment insofar as they share the common function of adjusting the temperature of hydrogen gas.

[0042] The upstream sections of the first compressor 50 and the second compressor 51 are fluidically connected to each other by a bypass channel 80C, and the downstream sections of the first compressor 50 and the second compressor 51 are fluidically connected to each other by a bypass channel 80D. As a result, the first compressor 50 and the second compressor 51, being of the same type, back up each other.

[0043] The first compressor 50 and the second compressor 51 have mutually replaceable performances. Specifically, the first compressor 50 has performances (for example, capacity, compression ratio, and operating temperature) that enable it to replace the second compressor 51, and the second compressor 51 has performances that enable it to replace the first compressor 50. In addition, both the first compressor 50 and the second compressor 51 have a capacity capable of processing boil-off gas generated in the tank 10. Here, the generation amount of boil-off gas can be predicted from the performance of the tank 10, and both the first compressor 50 and the second compressor 51 are designed to be capable of processing the generation amount of boil-off gas predicted from the performance of the tank 10. In this specification, the "capacity" of a device refers to the flow rate of gas that the device can process in a predetermined period of time. The capacity of the second compressor 51 of the present embodiment is larger than the capacity of the first compressor 50. In addition, the compression ratio of the second compressor 51 is lower than the compression ratio of the first compressor 50.

[0044] The upstream sides of the second heat exchanger 61 and the fourth heat exchanger 63 are fluidly connected to each other by a bypass flow path 80A, and the downstream sides of the second heat exchanger 61 and the fourth heat exchanger 63 are fluidly connected to each other by a bypass flow path 80C. Accordingly, the second heat exchanger 61 and the fourth heat exchanger 63, which are of the same type as each other, mutually back up each other.

[0045] The second heat exchanger 61 and the fourth heat exchanger 63 have mutually replaceable performances. Specifically, the second heat exchanger 61 has performances (for example, capacity and temperature increase range) that enable it to replace the fourth heat exchanger 63, and the fourth heat exchanger 63 has performances that enable it to replace the second heat exchanger 61. In addition, both the second heat exchanger 61 and the fourth heat exchanger 63 have a capacity capable of processing boil-off gas generated in the tank 10. The capacity of the fourth heat exchanger 63 is larger than the capacity of the second heat exchanger 61.

[0046] Upstream sides of the first heat exchanger 60 and the third heat exchanger 62 are fluidly connected to each other via a bypass flow path 80D, and downstream sides of the first heat exchanger 60 and the third heat exchanger 62 are fluidly connected to each other via a bypass flow path 80B. Accordingly, the first heat exchanger 60 and the third heat exchanger 62, which are of the same type as each other, mutually back up each other.

[0047] The first heat exchanger 60 and the third heat exchanger 62 have mutually replaceable performances. Specifically, the first heat exchanger 60 has performance capable of replacing the third heat exchanger 62 (for example, capacity and temperature increase width), and the third heat exchanger 62 has performance capable of replacing the first heat exchanger 60. Further, both the first heat exchanger 60 and the third heat exchanger 62 have a capacity capable of processing boil-off gas generated in the tank 10. The capacity of the third heat exchanger 62 is larger than the capacity of the first heat exchanger 60. Further, the temperature increase width of the third heat exchanger 62 is larger than the temperature increase width of the first heat exchanger 60. Accordingly, the temperature of hydrogen gas that has passed through the third heat exchanger 62 can be made higher than the temperature of hydrogen gas that has passed through the first heat exchanger 60.

[0048] Hereinafter, a method in which devices arranged in the first supply flow path 20 and devices arranged in the second supply flow path 30 mutually back up each other will be described.

[0049] FIG. 2 and FIG. 3 are diagrams showing the flow of hydrogen gas in the liquefied gas facility 1 when hydrogen gas is supplied from the tank 10 to the combustion device 40. Specifically, FIG. 2 and FIG. 3 show the flow of hydrogen gas in the liquefied gas facility 1 when boil-off gas is supplied from the tank 10 to the combustion device 40 in order to adjust the pressure in the tank 10. FIG. 2 shows the flow of hydrogen gas in the liquefied gas facility 1 when all devices arranged in the first supply flow path 20, that is, the first compressor 50, the first heat exchanger 60, and the second heat exchanger 61 are operating normally. FIG. 3 shows the flow of hydrogen gas in the liquefied gas facility 1 when an abnormality occurs in the second heat exchanger 61.

[0050] In Figure 2, all of the first valves 70A to 70C are open, and all of the third valves 72A to 72D are closed. As a result, the boil-off gas taken out of the tank 10 flows through the first supply channel 20 and is supplied to the combustion device 40. The boil-off gas supplied to the combustion device 40 is processed by combustion in the combustion device 40. This lowers the pressure inside the tank 10 and prevents the pressure inside the tank 10 from rising excessively. As a result, the pressure inside the tank 10 is prevented from exceeding the allowable pressure of the tank 10.

[0051] In Figure 3, the first valves 70A, 70B, the second valve 71C, and the third valves 72A, 72C are open, while the first valve 70C, the second valves 71A, 71B, and the third valves 72B, 72D are closed. The boil-off gas taken out of the tank 10 into the first supply channel 20 flows through the bypass channel 80A and into the second supply channel 30 from the connection part 31. The boil-off gas that flows into the second supply channel 30 passes through the fourth heat exchanger 63, is heated, and then returns to the first supply channel 20 via the bypass channel 80C and the connection part 23. After that, the boil-off gas flows sequentially through the first compressor 50 and the first heat exchanger 60 before being supplied to the combustion device 40. In this way, when a malfunction occurs in the second heat exchanger 61, the fourth heat exchanger 63 functions in place of the second heat exchanger 61.

[0052] Although not shown in the diagram, when a malfunction occurs in the first compressor 50, the second compressor 51 functions in place of the first compressor 50 by using the bypass passages 80C and 80D. Similarly, when a malfunction occurs in the first heat exchanger 60, the third heat exchanger 62 functions in place of the first heat exchanger 60 by using the bypass passages 80B and 80D.

[0053] Figures 4 and 5 show the flow of hydrogen gas within the liquefied gas equipment 1 when warming up tank 10. Figure 4 shows the flow of hydrogen gas within the liquefied gas equipment 1 when all equipment located in the second supply channel 30, namely the second compressor 51, the third heat exchanger 62, and the fourth heat exchanger 63, are operating normally. Figure 5 shows the flow of hydrogen gas within the liquefied gas equipment 1 when an abnormality occurs in the fourth heat exchanger 63. As shown in Figures 4 and 5, during the warm-up of tank 10, there is no liquefied hydrogen in tank 10, only hydrogen gas. During the warm-up of tank 10, the hydrogen gas present in tank 10 is used to raise the temperature of tank 10.

[0054] In Figure 4, all of the second valves 71A to 71C are open, and all of the third valves 72A to 72D are closed. As a result, the hydrogen gas taken out of tank 10 is pressurized and heated as it flows through the second supply channel 30 and returned to tank 10. This causes tank 10 to be heated.

[0055] In Figure 5, the first valve 70C, the second valves 71A and 71B, and the third valves 72A and 72C are open, while the first valves 70A and 70B, the second valve 71C, and the third valves 72B and 72D are closed. Hydrogen gas taken out of the tank 10 into the second supply channel 30 flows through the bypass channel 80A and into the first supply channel 20 from the connection 21. The hydrogen gas that flows into the first supply channel 20 passes through the second heat exchanger 61, is heated, and then returns to the second supply channel 30 via the bypass channel 80C and the connection 33. After that, the hydrogen gas flows sequentially through the second compressor 51 and the third heat exchanger 62 before being supplied to the tank 10. In this way, when a malfunction occurs in the fourth heat exchanger 63, the second heat exchanger 61 functions in place of the fourth heat exchanger 63.

[0056] Although not shown in the diagram, when a malfunction occurs in the second compressor 51, the first compressor 50 functions in place of the second compressor 51 by using the bypass passages 80C and 80D. Similarly, when a malfunction occurs in the third heat exchanger 62, the first heat exchanger 60 functions in place of the third heat exchanger 62 by using the bypass passages 80B and 80D.

[0057] A malfunction in the equipment such as the first and second compressors 50 and 51, and the first to fourth heat exchangers 60 to 63 means that the equipment is not operating normally. A malfunction in the compressor may include a state in which the discharge pressure of the compressor has not risen to a predetermined pressure. Such a malfunction can be detected by referring to the pressure measured by a pressure gauge (not shown) located downstream of the compressor. Similarly, a malfunction in the heat exchanger may include a state in which the temperature of the hydrogen gas that has passed through the heat exchanger has not risen to a predetermined temperature. Such a malfunction can be detected by referring to the temperature measured by a thermometer (not shown) located downstream of the heat exchanger. The forms of equipment malfunctions and the detection of equipment malfunctions are not limited to these examples.

[0058] The liquefied gas equipment 1 of this embodiment provides the following effects and advantages.

[0059] The liquefied gas equipment 1 according to this embodiment includes: a tank 10 for storing liquefied gas (in this embodiment, liquefied hydrogen); a first supply channel 20 for supplying gas (in this embodiment, hydrogen gas) generated by the vaporization of liquefied hydrogen from the tank 10 to a supply destination (in this embodiment, a combustion device 40); a second supply channel 30 for supplying hydrogen gas from the tank 10 to a supply destination (in this embodiment, the tank 10) different from the supply destination of the first supply channel 20; a first device (in this embodiment, a second heat exchanger 61) arranged in the first supply channel 20 for adjusting the pressure or temperature of the hydrogen gas; and a second device (in this embodiment, a fourth heat exchanger 63) of the same type as the second heat exchanger 61 arranged in the second supply channel 30 for adjusting the pressure or temperature of the hydrogen gas. The system includes a first bypass channel (bypass channel 80A in this embodiment) connecting a first connection (connection 21 in this embodiment) located upstream of the second heat exchanger 61 in the first supply channel 20 and a second connection (connection 31 in this embodiment) located upstream of the fourth heat exchanger 63 in the second supply channel 30, and a second bypass channel (bypass channel 80B in this embodiment) connecting a third connection (connection 22 in this embodiment) located downstream of the second heat exchanger 61 in the first supply channel 20 and a fourth connection (connection 32 in this embodiment) located downstream of the fourth heat exchanger 63 in the second supply channel 30.

[0060] According to this embodiment, redundancy can be provided to the liquefied gas equipment 1 while suppressing cost increases. The upstream sides of the second and fourth heat exchangers 61 and 63, which are located in the first and second supply channels 20 and 30 respectively, are connected to each other by a bypass channel 80A, and the downstream sides of the second and fourth heat exchangers 61 and 63 are connected to each other by a bypass channel 80B. As a result, the second and fourth heat exchangers 61 and 63, which are of the same type and are located in the first and second supply channels 20 and 30 respectively for supplying hydrogen gas to different destinations, can back each other up. Consequently, compared to a configuration in which a heat exchanger is installed in each of the first and second supply channels 20 and 30 to ensure redundancy, redundancy can be provided to the liquefied gas equipment 1 while suppressing cost increases.

[0061] The liquefied gas equipment 1 according to this embodiment includes a third piece of equipment (a first compressor 50 in this embodiment) of a different type from the second heat exchanger 61 and the fourth heat exchanger 63, which are located downstream of the second heat exchanger 61 in the first supply channel 20 and adjust the pressure or temperature of the hydrogen gas, and a fourth piece of equipment (a second compressor 51 in this embodiment) of the same type as the first compressor 50, which are located downstream of the fourth heat exchanger 63 in the second supply channel 30 and adjust the pressure or temperature of the hydrogen gas.

[0062] According to this embodiment, redundancy can be provided to the liquefied gas equipment 1. By bypass channels 80A and 80B, the second heat exchanger 61 and the first compressor 50 located in the first supply channel 20, and the fourth heat exchanger 63 and the second compressor 51 located in the second supply channel 30, can back up each other with equipment of the same type. As a result, redundancy can be provided to the liquefied gas equipment 1.

[0063] The liquefied gas equipment 1 according to this embodiment includes a third bypass channel (bypass channel 80C in this embodiment) that connects a fifth connection (connection 23 in this embodiment) located downstream of the second heat exchanger 61 and upstream of the first compressor 50 in the first supply channel 20, and a sixth connection (connection 33 in this embodiment) located downstream of the fourth heat exchanger 63 and upstream of the second compressor 51 in the second supply channel 30.

[0064] According to this embodiment, redundancy can be provided to the liquefied gas equipment 1. By bypass channels 80A and 80C, the second and fourth heat exchangers 61 and 63 of the same type, which are located in the first and second supply channels 20 and 30, can back up each other. Also, by bypass channels 80B and 80C, the first and second compressors 50 and 51 of the same type, which are located in the first and second supply channels 20 and 30, can back up each other. In other words, backup of the second and fourth heat exchangers 61 and 63 of the same type and backup of the first and second compressors 50 and 51 of the same type can be performed separately. As a result, redundancy can be provided to the liquefied gas equipment 1.

[0065] In this embodiment, the first compressor 50 is a compressor that increases the pressure of hydrogen gas flowing through the first supply channel 20, the second heat exchanger 61 is a heat exchanger that adjusts the temperature of the hydrogen gas supplied to the first compressor 50, the second compressor 51 is a compressor that increases the pressure of hydrogen gas flowing through the second supply channel 30, and the fourth heat exchanger 63 is a heat exchanger that adjusts the temperature of the gas supplied to the second compressor 51.

[0066] According to this embodiment, redundancy can be provided to the liquefied gas equipment 1. The boil-off gas produced when liquefied hydrogen vaporizes due to natural heat input is at an extremely low temperature (for example, around -250°C). In a configuration where hydrogen gas is directly supplied from the tank 10 to the first and second compressors 50 and 51, it is necessary to use special compressors capable of operating at extremely low temperatures as the first and second compressors 50 and 51. In contrast, in this embodiment, the second heat exchanger 61 adjusts the temperature of the hydrogen gas supplied to the first compressor 50, and the fourth heat exchanger 63 adjusts the temperature of the hydrogen gas supplied to the second compressor 51. Therefore, by raising the temperature of the hydrogen gas supplied to the first and second compressors 50 and 51 by the second and fourth heat exchangers 61 and 63 to, for example, above the boiling point of methane, conventional compressors such as compressors for liquefied natural gas equipment can be used as the first and second compressors 50 and 51. Furthermore, in this configuration, the liquefied gas equipment 1 can be made redundant by having the second heat exchanger 61 and the fourth heat exchanger 63 back up each other.

[0067] In this embodiment, the second heat exchanger 61 is a heat exchanger that adjusts the temperature of the hydrogen gas flowing through the first supply channel 20, and the fourth heat exchanger 63 is a heat exchanger that adjusts the temperature of the hydrogen gas flowing through the second supply channel 30. The capacities of the second heat exchanger 61 and the fourth heat exchanger 63 are greater than the capacity to handle the amount of boil-off gas generated from the tank 10.

[0068] According to this embodiment, redundancy can be provided to the liquefied gas equipment 1. Even if any of the second or fourth heat exchangers 61 or 63 fail, the remaining heat exchangers can process the boil-off gas from the tank 10. As a result, it is possible to suppress an excessive rise in pressure inside the tank 10 due to the boil-off gas, and to prevent the pressure inside the tank 10 from exceeding the allowable pressure of the tank 10. This allows redundancy to be provided to the liquefied gas equipment.

[0069] In this embodiment, the first supply channel 20 is a channel that supplies hydrogen gas taken out of the tank 10 to a combustion device 40 that burns it, the second supply channel 30 is a channel that returns the hydrogen gas taken out of the tank 10 to the tank 10, the second heat exchanger 61 is a heat exchanger that adjusts the temperature of the hydrogen gas flowing through the first supply channel 20, the fourth heat exchanger 63 is a heat exchanger that adjusts the temperature of the hydrogen gas flowing through the second supply channel 30, and the capacity of the fourth heat exchanger 63 is greater than the capacity of the second heat exchanger 61.

[0070] According to this disclosure, redundancy can be provided to the liquefied gas equipment 1. When boil-off gas generated from tank 10 is processed by combustion device 40, if the capacity of the fourth heat exchanger 63 is smaller than the capacity of the second heat exchanger 61, the boil-off gas generated from tank 10 may not be processed if the second heat exchanger 61 fails. As a result, the pressure inside tank 10 may not be kept below the allowable pressure. In contrast, according to the liquefied gas equipment 1 of this embodiment, even if the second heat exchanger 61 fails, the boil-off gas from tank 10 can be processed by the fourth heat exchanger 63. As a result, redundancy can be provided to the liquefied gas equipment 1.

[0071] The vessel according to this embodiment is equipped with a liquefied gas facility 1.

[0072] The liquefied gas equipment 1 in this embodiment is particularly advantageous when installed on a ship with limited installation space, because it eliminates the need to install extra equipment for redundancy. Furthermore, by applying the liquefied gas equipment 1 according to this embodiment to a ship, the ship can be made compliant with the availability rules stipulated in the IGC Code, which is an international rule.

[0073] (Modifications) This disclosure is not limited to the configurations described in the embodiments above, and various modifications are possible.

[0074] Figure 6 is a schematic diagram showing the configuration of a liquefied gas equipment 1 according to one modified example of the above embodiment. The liquefied gas equipment 1 according to the modified example shown in Figure 6 has the same configuration as the liquefied gas equipment 1 according to the above embodiment, except that the first supply channel 20 and the second supply channel 30 supply hydrogen gas to the same destination.

[0075] Referring to Figure 6, the second supply channel 30 in this modified example is a channel for vaporizing the liquefied hydrogen taken from the tank 10 and supplying the resulting hydrogen gas as fuel gas to the combustion device 40. The liquefied gas equipment 1 in this modified example is located upstream of the fourth heat exchanger 63 in the second supply channel 30 and includes a vaporizer 90 for vaporizing the liquefied hydrogen taken from the tank 10. The vaporizer 90 is located upstream of the connection section 31 in the second supply channel 30.

[0076] According to this modified example, the liquefied gas equipment 1 provides the following effects.

[0077] The liquefied gas equipment 1 according to this modified example comprises: a tank 10 for storing liquefied gas (liquefied hydrogen in this modified example); a first supply channel 20 for supplying gas (hydrogen gas in this modified example) generated by the vaporization of liquefied hydrogen to a supply destination (combustion device 40 in this modified example); a second supply channel 30 for supplying hydrogen gas from the tank 10 to the same supply destination as the supply destination of the first supply channel 20; a first device (second heat exchanger 61 in this modified example) located in the first supply channel 20 for adjusting the pressure or temperature of the hydrogen gas; a second device (fourth heat exchanger 63 in this modified example) of the same type as the second heat exchanger 61 located in the second supply channel 30 for adjusting the pressure or temperature of the hydrogen gas; and a third device (first compressor 50 in this modified example) of a different type from the second heat exchanger 61 and the fourth heat exchanger 63 located downstream of the second heat exchanger 61 in the first supply channel 20 for adjusting the pressure or temperature of the hydrogen gas. A second compressor 51 of the same type as the first compressor 50, located downstream of the fourth heat exchanger 63 in the second supply channel 30, which adjusts the pressure or temperature of the hydrogen gas; a first bypass channel (bypass channel 80A in this modified example) connecting a first connection (connection 21 in this modified example) located upstream of the second heat exchanger 61 in the first supply channel 20 and a second connection (connection 31 in this modified example) located upstream of the fourth heat exchanger 63 in the second supply channel 30; a second bypass channel (bypass channel 80B in this modified example) connecting a third connection (connection 22 in this modified example) located downstream of the first compressor 50 in the first supply channel 20 and a fourth connection (connection 32 in this modified example) located downstream of the second compressor 51 in the second supply channel 30; The system includes a fifth connection point (connection point 23 in this modified example) located downstream of the second heat exchanger 61 and upstream of the first compressor 50 in the first supply channel 20, and a third bypass channel (bypass channel 80C in this modified example) connecting the sixth connection point (connection point 33 in this modified example) located downstream of the fourth heat exchanger 63 and upstream of the second compressor 51 in the second supply channel 30.

[0078] According to this modified example, redundancy can be provided to the liquefied gas equipment 1. By bypass channels 80A and 80C, the second and fourth heat exchangers 61 and 63 of the same type, located in the first and second supply channels 20 and 30, can back up each other. Also, by bypass channels 80B and 80C, the first and second compressors 50 and 51 of the same type, located in the first and second supply channels 20 and 30, can back up each other. In other words, backup of the second and fourth heat exchangers 61 and 63 of the same type and backup of the first and second compressors 50 and 51 of the same type can be performed separately. As a result, redundancy can be provided to the liquefied gas equipment 1.

[0079] (Other Modifications) In the above embodiment, an example was described in which the liquefied gas equipment 1 is installed on a ship, but the liquefied gas equipment according to this disclosure may be installed, for example, on a floating structure or on land.

[0080] In the above embodiment, an example was described in which the first supply channel 20 is supplied to a combustion device 40. However, the supply destination of the first supply channel according to this disclosure is not limited to a combustion device that burns gas generated by the vaporization of liquefied gas. Furthermore, in the above embodiment, an example was described in which the first supply channel 20 is used to supply hydrogen gas to the combustion device 40. However, the first supply channel according to this disclosure may be used for different operations.

[0081] In the above embodiment, an example was described in which the destination of the second supply channel 30 is a tank 10, but the destination of the second supply channel according to this disclosure is not limited to a tank for storing liquefied gas. Also, in the above embodiment, an example was described in which the second supply channel 30 is used to warm up the tank 10, but the second supply channel according to this disclosure may be used for different operations.

[0082] In the above embodiments, an example was described in which the liquefied gas according to the disclosure is liquefied hydrogen. However, the liquefied gas according to the disclosure may be other liquefied gases such as liquefied natural gas (LNG) or liquefied petroleum gas (LPG). In other words, the gas generated when the liquefied gas according to the disclosure vaporizes may be other gases such as methane, propane, or butane.

[0083] In the above embodiment, an example was described in which the tank 10 is a cargo tank, but the tank 10 may also be a fuel tank that contains liquefied gas as fuel.

[0084] In the above embodiment, an example was described in which the combustion device according to the disclosure is a boiler, but the combustion device according to the disclosure may be other combustion devices such as a gas combustion unit (GCU).

[0085] In the above embodiment, an example was described in which the first and second devices according to the disclosure are a second heat exchanger 61 and a fourth heat exchanger 63, respectively, and the third and fourth devices according to the disclosure are a first compressor 50 and a second compressor 51, respectively, but the invention is not limited thereto.

[0086] The first device relating to this disclosure may be a first compressor 50, and the second device relating to this disclosure may be a second compressor 51. In this case, the third device relating to this disclosure may be a first heat exchanger 60, and the fourth device relating to this disclosure may be a third heat exchanger 62. In this case, the first bypass flow path relating to this disclosure may be a bypass flow path 80C, the second bypass flow path relating to this disclosure may be a bypass flow path 80B, and the third bypass flow path relating to this disclosure may be a bypass flow path 80D.

[0087] The first device relating to this disclosure may be a first heat exchanger 60, and the second device relating to this disclosure may be a third heat exchanger 62. In this case, the third device relating to this disclosure may be another device located downstream of the first heat exchanger 60, and the fourth device relating to this disclosure may be another device located downstream of the third heat exchanger 62. In this case, the first bypass channel relating to this disclosure may be a bypass channel 80D, and the second bypass channel relating to this disclosure may be a bypass channel 80B.

[0088] In the above embodiment, an example was described in which the first and second devices of the disclosure are heat exchangers and the third and fourth devices of the disclosure are compressors. However, the first to fourth devices of the disclosure may be of a different type than heat exchangers or compressors.

[0089] In the above embodiment, the fourth heat exchanger 63 functioned as a heater, but if the second supply channel 30 is used, for example, for reliquefaction of boil-off gas, the fourth heat exchanger 63 may be used as a cooler.

Claims

1. A liquefied gas facility comprising: a tank for storing liquefied gas; a first supply channel for supplying gas generated by the vaporization of the liquefied gas from the tank to a destination; a second supply channel for supplying the gas from the tank to a destination different from the destination of the first supply channel; a first device arranged in the first supply channel for adjusting the pressure or temperature of the gas; a second device of the same type as the first device arranged in the second supply channel for adjusting the pressure or temperature of the gas; a first bypass channel connecting a first connection located upstream of the first device in the first supply channel and a second connection located upstream of the second device in the second supply channel; and a second bypass channel connecting a third connection located downstream of the first device in the first supply channel and a fourth connection located downstream of the second device in the second supply channel.

2. The liquefied gas equipment according to claim 1, comprising: a third device of a different type from the first and second devices, which is located downstream of the first device in the first supply channel and adjusts the pressure or temperature of the gas; and a fourth device of the same type as the third device, which is located downstream of the second device in the second supply channel and adjusts the pressure or temperature of the gas.

3. The liquefied gas equipment according to claim 2, further comprising a third bypass channel connecting a fifth connection located downstream of the first equipment and upstream of the third equipment in the first supply channel, and a sixth connection located downstream of the second equipment and upstream of the fourth equipment in the second supply channel.

4. The liquefied gas equipment according to claim 3, wherein the third device is a compressor for increasing the pressure of the gas flowing through the first supply channel, the first device is a heat exchanger for adjusting the temperature of the gas supplied to the third device, the fourth device is a compressor for increasing the pressure of the gas flowing through the second supply channel, and the second device is a heat exchanger for adjusting the temperature of the gas supplied to the fourth device.

5. The liquefied gas apparatus according to claim 1, wherein the first device is a heat exchanger that adjusts the temperature of the gas flowing through the first supply channel, and the second device is a heat exchanger that adjusts the temperature of the gas flowing through the second supply channel, and the capacity of each of the first and second devices is greater than the capacity capable of handling the amount of boil-off gas generated from the tank.

6. The liquefied gas equipment according to claim 5, wherein the first supply channel is a channel for supplying the gas taken out of the tank to a combustion device for burning the gas, the second supply channel is a channel for returning the gas taken out of the tank to the tank, the first device is a heat exchanger for adjusting the temperature of the gas flowing through the first supply channel, the second device is a heat exchanger for adjusting the temperature of the gas flowing through the second supply channel, and the capacity of the second device is greater than the capacity of the first device.

7. A tank for storing liquefied gas; a first supply channel for supplying gas generated by the vaporization of the liquefied gas to a destination; a second supply channel for supplying the gas from the tank to the same destination as the first supply channel; a first device arranged in the first supply channel for adjusting the pressure or temperature of the gas; a second device of the same type as the first device arranged in the second supply channel for adjusting the pressure or temperature of the gas; a third device of a different type from the first and second devices, arranged downstream of the first device in the first supply channel for adjusting the pressure or temperature of the gas; a fourth device of the same type as the third device, arranged downstream of the second device in the second supply channel for adjusting the pressure or temperature of the gas; a first bypass channel connecting a first connection located upstream of the first device in the first supply channel and a second connection located upstream of the second device in the second supply channel. A liquefied gas facility comprising: a second bypass channel connecting a third connection located downstream of the third device in the first supply channel and a fourth connection located downstream of the fourth device in the second supply channel; a third bypass channel connecting a fifth connection located downstream of the first device and upstream of the third device in the first supply channel and a sixth connection located downstream of the second device and upstream of the fourth device in the second supply channel.

8. A ship equipped with the liquefied gas equipment described in claim 1 or 7.

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