Hydrogen liquefaction with stored hydrogen refrigeration source

Abstract

Systems and methods for liquefying a hydrogen feed stream use a high pressure hydrogen stream from a storage source to provide refrigeration for the system. After providing refrigeration to the system, hydrogen from the high pressure storage source is at a pressure not lower than a cold box feed stream of the system, where the cold box feed stream includes a hydrogen feed stream and at least one recycle stream and is not recycled back through the system, but rather leaves the system.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of U.S. Provisional Application No. 63 / 276,888, filed on November 8, 2021, the contents of which are incorporated herein by reference. Technical Field

[0003] The present invention relates generally to systems and methods for liquefying hydrogen, and more particularly to systems and methods for liquefying hydrogen and using hydrogen storage as a refrigerant source. Background Art

[0004] Industrial gases, such as natural gas or hydrogen, are advantageously stored or transported in liquid form because they occupy a much smaller volume (e.g., natural gas is 1 / 600 of the gaseous state). The liquefied gas is then evaporated back into the gaseous state for use on site or in the system.

[0005] Gaseous hydrogen is converted to liquid hydrogen by cooling to at least about -253° C. Typical cooling processes utilize large amounts of energy and can be very expensive in terms of equipment costs. The process may include multiple refrigeration cycles and involve multiple stages of gas compression.

[0006] U.S. Patent No. 10,634,425 to Guillard et al. describes the use of exhaust energy from high pressure gas to provide refrigeration and reduce operating costs in a hydrogen liquefaction system. The '425 patent uses exhaust energy from a high pressure gas other than hydrogen to provide cooling at the hot end of the system and uses a methanol production unit as a source of high pressure hydrogen-rich purge gas for exhaust refrigeration energy to provide cooling at the cold end of the system. After being used to provide cooling, the hydrogen-rich stream is sent back to the methanol plant as low pressure fuel.

[0007] It would be desirable to provide a hydrogen liquefaction system and method that reduces operating and equipment costs in at least some applications. Summary of the invention

[0008] Aspects of the present subject matter may be implemented individually or together in the methods, devices, and systems described and claimed below. These aspects may be used alone or in combination with other aspects of the subject matter described herein, and the description of these aspects is not intended to exclude the individual use of these aspects or the individual claims of these aspects or the different combinations set forth in the appended claims.

[0009] In one aspect, a system for liquefying a hydrogen feed stream includes a cold box feed line configured to receive a cold box feed stream having a cold box feed stream pressure, wherein the cold box feed stream includes at least a hydrogen feed stream. A heat exchanger system has a liquefier cooling passage in fluid communication with the cold box feed line and is configured to receive and cool the liquefier stream, thereby forming a product stream. A product expansion device is in fluid communication with an outlet of the liquefier cooling passage and is configured to receive the product stream, thereby forming an expanded product stream.

[0010] The heat exchanger system includes a refrigerant cooling passage configured to receive a refrigerant feed stream to form a cooled refrigerant feed stream. A refrigerant expansion device is in fluid communication with the refrigerant cooling passage of the heat exchanger system to form an expanded refrigerant stream. The heat exchanger system includes a refrigerant heating passage in fluid communication with an outlet of the refrigerant expansion device to provide cooling in the heat exchanger system.

[0011] The heat exchanger system includes a first hydrogen high-pressure refrigerant cooling passage configured to receive and cool a high-pressure hydrogen supplemental refrigerant feed stream to form a cooled hydrogen supplemental refrigerant stream. The supplemental refrigerant expansion device has an inlet fluidly connected to the first hydrogen high-pressure refrigeration cooling passage to produce an expanded hydrogen supplemental refrigerant stream having a pressure not less than the pressure of the cold box feed stream. The heat exchanger system includes a high-pressure hydrogen refrigerant heating passage fluidly connected to the outlet of the supplemental refrigerant expansion device and configured to receive the expanded hydrogen supplemental refrigerant stream to provide cooling in the heat exchanger system and form a high-pressure hydrogen product stream having a pressure greater than the pressure of the cold box feed stream.

[0012] In another aspect, a method for liquefying a hydrogen feed stream comprises the steps of: receiving a cold box feed stream comprising at least a hydrogen feed stream into a heat exchanger system, wherein the cold box feed stream has a cold box feed stream pressure; cooling a liquefier feed stream comprising the cold box feed stream in the heat exchanger system to form a product stream; expanding the product stream to form an expanded product stream; cooling a refrigerant stream in the heat exchanger system to form a cooled refrigerant stream; expanding the cooled refrigerant stream to form a first expanded refrigerant stream; heating the first expanded refrigerant stream to provide cooling in the heat exchanger system; cooling a high pressure hydrogen make-up refrigerant feed stream in the heat exchanger system to form a cooled hydrogen make-up refrigerant stream; expanding the cooled hydrogen make-up refrigerant stream to form an expanded hydrogen make-up refrigerant stream having a pressure not less than the pressure of the cold box feed stream; and heating the expanded make-up hydrogen refrigerant stream to provide cooling in the heat exchanger system and form a high pressure hydrogen product stream having a pressure greater than the pressure of the cold box feed stream. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 is a process flow diagram and schematic diagram illustrating an embodiment of a hydrogen liquefaction system of the present disclosure.

[0014] Figure 2 are process flow diagrams and schematics illustrating alternative embodiments of the hydrogen liquefaction system of the present disclosure. DETAILED DESCRIPTION

[0015] According to the present disclosure, hydrogen from high pressure storage, such as hydrogen storage caverns, high pressure gas cylinders, hydrogen pipelines and / or other high pressure storage or components is used to provide refrigeration to a hydrogen liquefaction system. The high pressure hydrogen then leaves the system as a hydrogen stream that can be utilized by different systems and / or processes. Using a stored high pressure hydrogen source, including the depressurization energy provided by such a source, eliminates or greatly reduces the need for refrigeration from other sources, reducing the power required and operating costs.

[0016] Figure 1 A process flow diagram and schematic diagram illustrating an embodiment of a hydrogen liquefaction system of the present disclosure are provided in FIG.

[0017] It should be noted here that pipelines, conduits, pipes, channels and similar structures and corresponding flows are sometimes represented by the same element numbers shown in the figures. In addition, as used herein, and as known in the art, a heat exchanger is a device or a region in a device in which indirect heat exchange occurs between two or more flows at different temperatures, or between a flow and an environment. In addition, all heat exchangers mentioned herein may be incorporated into one or more heat exchanger devices, or may each be a separate heat exchanger device. As used herein, unless otherwise specified, the term "communication" and the like generally refer to fluid communication. And although the two fluids in communication can exchange heat when mixed, such exchange will not be considered to be the same as the heat exchange in a heat exchanger, although such exchange may occur in a heat exchanger. A heat exchange system or heat exchanger system may include items that are not specifically described but are generally known in the art as a part of a heat exchanger, such as an expansion device, a flash valve, etc. As used herein, the terms "high", "medium", "warm", "cold", etc. are relative to comparable flows, as is customary in the art.

[0018] refer to Figure 1 In the embodiment of the present invention, the hydrogen feed stream 3 is combined with the first hydrogen recycle stream and then combined with the second medium-pressure hydrogen recycle stream 2. The first hydrogen recycle stream is formed by compressing the low-pressure hydrogen recycle stream 1 in the first hydrogen compressor 101. The resulting mixture is fed to the second hydrogen compressor 102 at approximately ambient temperature. The fluid leaves the second hydrogen compressor as the hydrogen cold box feed stream 4.

[0019] The hydrogen cold box feed stream 4 may have a pressure of about 200-600 psig, preferably 250-400 psig. The first and second hydrogen compressors 101 and 102 may each be comprised of a single compressor or compressor stage or more than one compressor or compressor stage. Alternatively, compressors 101 and 102 may represent stages of the same compressor with at least one interstage feed. If the pressure of the hydrogen feed 3 is high enough to feed the cold box, compression of this stream is unnecessary and it may be combined with the recycle stream downstream of the second compressor 102, such as Figure 1 As shown by the dotted line at 130.

[0020] The hydrogen cold box feed 4 is cooled to about 80°K in the first heat exchanger 103 to form a first adsorber feed vapor 5 which is fed to a first adsorber system 104 which removes trace impurities to prevent impurity freezing and subsequent plugging of the heat exchanger channels. Figure 1 The first adsorber system 104 shown is generally constructed of parallel vessels and on-off valves to allow regeneration of saturated adsorber vessels in continuous operation. Suitable adsorber systems are well known in the art.

[0021] The stream leaving the first adsorber is split or divided into a liquefier feed stream 6 and a hydrogen refrigerant stream 7. Preferably, about 20% of this stream will become the liquefier feed 6 and the remainder will become the hydrogen refrigerant 7.

[0022] The liquefier feed 6 is further cooled in a second heat exchanger 106, which includes a second heat exchanger catalyst channel 107 containing an ortho-para conversion catalyst. The ortho-para conversion catalyst converts a portion of the orthohydrogen to parahydrogen during the liquefaction process to minimize the volatilization of the liquid product. Alternatively, one or more catalytic reactors outside the heat exchanger can be used. Suitable catalysts, such as iron oxide, chromium oxide or vanadium oxide, are well known in the art.

[0023] The liquefier feed 6 leaves the second heat exchanger 106 as a cooled liquefier feed stream 8. The cooled liquefier feed 8 is further cooled in the third heat exchanger 109, the fourth heat exchanger 112, and the fifth heat exchanger 116, which contain third heat exchanger catalyst channels 110, fourth heat exchanger catalyst channels 113, and fifth heat exchanger catalyst channels 117, respectively, to produce a cooled high pressure hydrogen stream 11. Alternatively, one or more catalytic reactors external to the heat exchanger may be used instead of the catalyst within the heat exchanger channels 110, 113, and / or 117.

[0024] In alternative embodiments of the system, a single heat exchanger or more than three heat exchangers may replace the third to fifth heat exchangers (109, 112, and 116). In fact, a single heat exchanger or heat exchanger system may replace or may combine any or all of the first to fifth heat exchangers (103, 106, 109, 112, and / or 116).

[0025] The cold high pressure hydrogen stream 11 is expanded through a product expansion device 118 to further cool it and produce a mixed phase product stream or two-phase hydrogen stream 12 which is fed to a hydrogen product separator 119. Figure 1 As with any expansion device or valve disclosed in the invention, the product expansion device 118 may be a Joule-Thomson valve or any other type of expansion valve or expansion device known in the art, including but not limited to a turbine or an orifice. Figure 1 As is the case with any of the separators disclosed in, product separator 119 can be an accumulation drum or any other separation vessel or other type of separation device known in the art, including but not limited to a cyclone separator, a distillation unit, a coalescer, or a mesh or vane demister.

[0026] Liquid hydrogen product stream 13 exits the bottom of hydrogen product separator 119, while saturated hydrogen vapor stream 14 exits the top. Saturated hydrogen vapor stream 14 is heated in fifth heat exchanger 116, where it provides refrigeration to help produce cold high pressure hydrogen stream 11, and exits as heated hydrogen vapor stream 15.

[0027] The hydrogen refrigerant 7 is cooled in the second heat exchanger 106 and the third heat exchanger 109 to produce cooled hydrogen refrigerant streams 16 and 17, respectively. A first portion 18 of the cooled hydrogen refrigerant stream 17 is further cooled in the fourth heat exchanger 112 to produce a cooled high pressure hydrogen refrigerant stream 20, while the remaining portion or second portion 19 of the cooled hydrogen refrigerant 17 is fed to a cold expansion device, such as a cold expansion turbine 111, where it is expanded to a lower pressure and leaves as a cold turbine product 29 at a lower temperature.

[0028] The cold high pressure hydrogen refrigerant stream 20 is expanded in the refrigerant expansion device 114 to further cool it and produce a mixed phase or two-phase hydrogen refrigerant stream 21, which is fed to the hydrogen refrigerant separator 115. The liquid hydrogen refrigerant stream 22 leaves the bottom of the hydrogen refrigerant separator 115 and is fed to the fifth heat exchanger 116, where most of it is evaporated to provide refrigeration to the fifth heat exchanger 116 and leaves as a mixed phase hydrogen refrigerant stream 23, which is fed to the hydrogen refrigerant separator 115.

[0029] The hydrogen refrigerant vapor stream 24 leaving the hydrogen refrigerant separator 115 is combined with the heated hydrogen vapor 15 to form a cold low-pressure hydrogen refrigerant stream 25. The cold low-pressure hydrogen refrigerant stream 25 and the cold turbine product stream 29 are heated in the fourth heat exchanger 112 and the third heat exchanger 109 to form a hot low-pressure hydrogen refrigerant stream 27 and a hot turbine product 31. The hot low-pressure hydrogen refrigerant stream 27 is further heated in the second heat exchanger 106 and the first heat exchanger 103 to form a low-pressure hydrogen recycle stream 1. The hot turbine product stream 31 is further heated in the first heat exchanger 103 to form a medium-pressure hydrogen recycle stream 2.

[0030] A high pressure hydrogen supplemental refrigeration feed stream 41 at a pressure above about 600 psig, typically about 1000-2000 psig, is cooled in the first heat exchanger 103 and fed as stream 42 to a second adsorber system 105 operating at a higher pressure and temperature similar to the first adsorber system 104 to form a purified high pressure hydrogen stream 43 which is further cooled in the second heat exchanger 106 to form a hot expansion turbine feed 44 which is fed to a hot expansion device, such as a hot expansion turbine 108. The hot expansion turbine 108 operates at a higher temperature, higher inlet pressure, and higher outlet pressure than the cold expansion turbine 111 and forms a hot expansion turbine product 45 at a higher pressure than the hydrogen cold box feed 4 pressure. The warm expansion turbine product 45 is heated in the third heat exchanger 109 and the first heat exchanger 103 to form a high pressure hydrogen product 47 at a pressure lower than the high pressure stored hydrogen feed 41 but higher than the hydrogen cold box feed 4 pressure. The high pressure hydrogen product 47 may be supplied to a gas turbine, a chemical process, a pipeline, an energy production process, hydrogen storage or other application. Alternatively, the high pressure hydrogen product 47 may be supplied to a gas turbine for powering a compressor stage or compressors 101 and / or 102.

[0031] An external refrigerant, such as liquid or gaseous nitrogen, may be used to provide additional refrigeration for the process. A second heat exchanger refrigerant stream 51, such as liquid nitrogen or another source of refrigeration, is heated in the second heat exchanger 106 and / or the first heat exchanger 103 to provide additional cooling. A first heat exchanger refrigerant stream 54, such as cold gaseous nitrogen or another source of refrigeration, is heated in the first heat exchanger 103 to provide additional cooling.

[0032] As previously described, heat exchangers 103, 106, 109, 112, and 116 may be incorporated into a heat exchanger system. By way of example only, such a heat exchanger system may include a single heat exchanger, separate heat exchangers (e.g., Figure 1), or combined in multiple heat exchangers (e.g., 103 and 106 are combined in a first heat exchanger, and 109, 112, and 116 are combined in a second heat exchanger). In addition, in alternative embodiments of the disclosed system, the number of heat exchangers may be different from Figure 1 In addition, any heat exchanger can be divided into more than one exchanger.

[0033] In an alternative embodiment, a portion of the high pressure hydrogen product 47 can be used as cold box feed 4, such as Figure 1 This is shown by the dashed line at 132. This still saves hydrogen compression power and cost compared to a typical hydrogen liquefaction process, but does not provide a high pressure gas product that can be used as a gas turbine feed.

[0034] In another alternative embodiment, a portion of the hot expansion turbine product stream 45 may be further cooled and expanded in a valve or expander to provide additional refrigeration in heat exchangers 109 and / or 106 and / or 103 since stream 45 is already cold and available at a higher pressure.

[0035] Thus, embodiments of the disclosed systems and methods utilize energy stored in a high pressure storage system such as a hydrogen cavern, pipeline, fixed storage system, or other high pressure hydrogen storage to provide refrigeration for the liquefaction system, thereby improving system efficiency and saving equipment and / or operating costs. Figure 1 47) in can provide a source of hydrogen for additional systems or processes.

[0036] As mentioned earlier, enter Figure 1 The hydrogen stream 5 from the first adsorber 104 is divided into a liquefier feed stream 6 and a hydrogen refrigerant stream 7, wherein about 20% of stream 5 preferably becomes the liquefier feed stream 6 and the remainder becomes the hydrogen refrigerant 7. This is a much higher fraction of hydrogen than is typical in a standard hydrogen liquefaction process not combined with high pressure storage.

[0037] also, Figure 1 Embodiments utilize energy stored in a high pressure storage system, such as a hydrogen cavern, pipeline, fixed hydrogen storage system, or other high pressure storage system, to provide refrigeration for the liquefier while still recovering hydrogen at a pressure above the cold box feed pressure. This is a significant advantage where the cavern, pipeline, or other high pressure storage system and the liquefier are co-located.

[0038] Even if the recovered hydrogen (stream 47) is not at a higher pressure than the cold box feed 4, it may be useful to use the outlet hydrogen rather than recycling it back to the liquefier.

[0039] Example

[0040] The following example provides more information about one configuration of the present invention. It is not intended to limit the disclosed invention or the scope of the present disclosure. Figure 1 In the embodiment of the present invention, a hydrogen cold box feed stream 4 of 4886 lbmol / hr consisting of normal hydrogen is supplied to the process of this embodiment after leaving the second hydrogen compressor 102, which raises the pressure of the feed gas 4 to 360 psig. Operating at high pressure enables the cryogenic liquefaction process.

[0041] In this embodiment, the first heat exchanger 103 reduces the temperature of the stream to 81K. Trace impurities are removed in the first adsorber system 104, and the stream is divided into a liquefier feed 6 (1000 lbmol / hr) and a hydrogen refrigerant stream 7 (3886 lbmol / hr). This results in a 20-21% split of the feed stream sent to the liquefier, which is higher than conventional hydrogen liquefiers known in the art. The liquefier feed 6 is cooled from 81K to produce a cold high pressure hydrogen stream 11 at 22K in heat exchangers 106, 109, 112 and 116. This stream is expanded to 45 psia in the product expansion device 118 to form a liquid hydrogen product stream 13.

[0042] Hydrogen refrigerant stream 7 is cooled in heat exchangers 106 and 109 to produce a 51K cooled hydrogen refrigerant stream 17, which is divided into a first portion 18 (351 lbmol / hr), which is cooled to 27K in heat exchanger 112, and a second portion 19 (3553 lbmol / hr), which is fed to a cold expansion turbine 111. The second portion 19 is expanded from 356 psia to 35 psia in the turbine and cooled from 51K to 24K. The cold turbine product 29 is used to provide refrigeration in the heat exchanger. The first portion 18 is cooled in heat exchanger 112 to produce a 27K cold high pressure hydrogen refrigerant stream 20, which is expanded from 356 psia to 18 psia in the refrigerant expansion valve device 114, and cooled from 27K to 21K, and is partially condensed. The partially condensed stream is mixed with the mixed phase hydrogen refrigerant stream 23 and separated in the hydrogen refrigerant separator 115 to form a liquid hydrogen refrigerant stream 22 (1170 lbmol / hr) and a hydrogen refrigerant vapor stream 24 (351 lbmol / hr). The liquid hydrogen refrigerant stream is partially evaporated to provide cooling in the coldest heat exchanger 116 and returned to the hydrogen refrigerant separator. The refrigerant vapor stream provides cooling in the other heat exchangers 112, 109, 106 and 103. Liquid nitrogen 51 (106 lbmol / hr) and cold nitrogen vapor 54 (961 lbmol / hr) provide additional refrigeration.

[0043] In this example, the high pressure stored hydrogen feed 41 is fed to the heat exchanger system at 2780 lbmol / hr of standard hydrogen at 300K and 2000 psia and is cooled to 79K and then fed to the hot expansion turbine 108 where it is expanded to 500 psia and cooled to 55K. This is a sufficiently low temperature to provide refrigeration for the system and in effect replaces the standard warm expander of the prior art. In addition, the stream is recovered from the cold box at 498 psia as a high pressure hydrogen product 47. Recovering the stream at a pressure no less than that of the cold box feed can provide the combined benefits of recovering the hydrogen stream at high pressure for use outside the liquefier and reducing refrigeration requirements compared to conventional hydrogen liquefaction processes.

[0044] The conditions and composition of the selected streams in the above example are shown in Table 1.

[0045] Table 1

[0046]

[0047] In another embodiment, the hydrogen refrigerant is passed through a series of expanders operating at different pressures and / or temperatures, or is fed to a set of more than one parallel expanders also operating at different temperatures. In this case, an expander for the hydrogen supplemental refrigeration stream would be added to the standard hydrogen liquefaction process. Although this would represent an additional capital cost, operating and power costs could be reduced compared to standard processes known in the art. As hydrogen liquefaction becomes more common, these processes can become larger, and the reduction in operating costs could justify the additional capital costs. Additional high temperature hydrogen refrigerant expanders could also increase operational flexibility to accommodate fluctuating pressures in high pressure hydrogen storage sources. This can be beneficial because hydrogen storage pressures, such as those in caverns or pipelines, can fluctuate as supply and demand change.

[0048] In an alternative embodiment, reference Figure 1 ,exist Figure 1 The high-temperature hydrogen expander represented by the dotted line 134 receives a portion of the cooling hydrogen refrigerant stream 16 and returns the expansion / cooling stream 136 to the refrigeration stream 30 and / or the expansion / cooling stream 138 to the refrigeration stream 26. The high-temperature hydrogen expander 134 can be a turbine or any other expansion device known in the art. Therefore, the high-pressure expander 108 is connected in parallel with the high-temperature hydrogen expander 134 and bears some but not all of the refrigeration load. This means that the additional capital cost of the third expander system is required to save the power cost of part of the high-temperature expander 134. Compared with the operating cost, the relative importance of capital cost decreases as the scale of the plant increases, so this method becomes more economical as the scale of the plant increases.

[0049] exist Figure 2In the embodiment of the invention, a closed refrigeration loop is shown, rather than a hydrogen refrigeration system mixed with the feed. The closed refrigeration loop can use helium, hydrogen, a mixture of helium and neon, or other suitable refrigerants that do not freeze at the lowest temperature in the loop. Figure 2 All reference numerals repeated in Figure 1 The same stream or device as shown in .

[0050] and Figure 1 In contrast to the embodiment of Figure 2 In the embodiment of the invention, the heated hydrogen vapor 15 is not mixed with another stream before being heated in the heat exchanger system. Figure 2 In the heat exchanger configuration shown, the heated hydrogen vapor 15 is heated in the heat exchanger system into a first hydrogen vapor recycle stream 61, a second hydrogen vapor recycle stream 62 and a third hydrogen vapor recycle stream 63 before exiting as a hydrogen recycle stream 64. Figure 1 The low pressure hydrogen recycle stream 1 in is equivalent, but has a lower flow rate.

[0051] Figure 1 and Figure 2 The main difference between the two process configurations is Figure 2 In the closed-loop refrigeration cycle of the embodiment of Figure 2 In the closed loop refrigeration cycle of FIG. 2 , hot low-pressure refrigerant 71 is compressed in the refrigerant compressor 201 to form hot high-pressure refrigerant 72, which is partially cooled to about 80K in the heat exchanger system to form a refrigerant adsorber feed stream 73. The refrigerant adsorber feed stream 73 is fed to the low-temperature refrigerant adsorption system 202, which removes impurities from the refrigerant that may have been introduced into the closed loop to produce a refrigerant adsorber product stream 74. The low-temperature refrigerant adsorption system 202 can be smaller and regenerated less frequently than other adsorption systems because no impurities are continuously introduced into the stream.

[0052] The refrigerant adsorber product vapor 74 is further cooled in the heat exchanger system to produce a first cooled refrigerant stream 75 and a second cooled refrigerant stream 76. In one embodiment, a portion of the first cooled refrigerant stream 141 is expanded in a first refrigerant expander 140 to produce a first low pressure refrigerant stream 142, which provides cooling to the heat exchanger system. The expander provides additional cooling if the heat expansion turbine 108 cannot provide sufficient cooling.

[0053] A portion of the second cooling refrigerant stream 77 is expanded in the second refrigerant expander 203 to produce a second low-pressure refrigerant stream 78, which provides cooling for the heat exchanger system. The remaining portion of the second cooling refrigerant stream 82 is further cooled in the heat exchanger system to produce a cold high-pressure refrigerant stream 83, which is expanded in the third refrigerant expander 204 to produce a third low-pressure refrigerant stream 84, which provides cooling for the heat exchanger system. The third low-pressure refrigerant stream 84 is partially heated in the heat exchanger system to produce a hot third low-pressure refrigerant 85, which is mixed with the second low-pressure refrigerant stream 78 to produce a mixed low-pressure refrigerant 86, which is heated in the heat exchanger system into a first heating refrigerant stream 79, a second heating refrigerant stream 80, and a third heating refrigerant stream 81 before leaving as hot low-pressure refrigerant 71.

[0054] exist Figure 2 In an alternative to the configuration shown, the second and third refrigerant expanders 203 and 204 can be operated in series, rather than in parallel. In this case, the second low-pressure refrigerant stream 78 is fed to the third refrigerant expander 204 as a series expander feed 87. In this case, there is no second cooling refrigerant stream 82. In another alternative, a valve or other pressure reducing device can be used instead of an expander.

[0055] One advantage of a closed loop refrigeration system is that the ortho-para conversion of the cold box feed 4 can be started at a higher temperature. In this case, because the entire stream is liquefied, it is advantageous to start the ortho-para conversion in the first heat exchanger 103 by filling the ortho-para conversion catalyst 120 into the low temperature portion of the cold box feed channel. This allows 75% of the ortho-hydrogen feed to be converted to about 50% ortho-hydrogen before entering the first adsorber system 104.

[0056] While preferred embodiments of the present disclosure have been shown and described, it will be apparent to those skilled in the art that changes and modifications may be made thereto without departing from the spirit of the present disclosure, the scope of which is defined by the appended claims.

Claims

1. A system for liquefying a hydrogen feed stream, comprising: a. a cold box feed line configured to receive a cold box feed stream having a cold box feed stream pressure, wherein the cold box feed stream comprises at least a hydrogen feed stream; b. a heat exchanger system having a liquefier cooling channel in fluid communication with the cold box feed line and configured to receive and cool the liquefier stream to form a product stream; c. a product expansion device in fluid communication with the outlet of the liquefier cooling passage and configured to receive the product stream to form an expanded product stream; d. The heat exchanger system comprises a first refrigerant cooling channel configured to receive a refrigerant feed stream to form a cooling refrigerant feed stream; e. a first refrigerant expansion device in fluid communication with a first refrigerant cooling passage of the heat exchanger system, thereby forming a first expanded refrigerant flow; f. The heat exchanger system comprises a first refrigerant heating passage in fluid communication with an outlet of the first refrigerant expansion device, thereby providing cooling in the heat exchanger system; g. The heat exchanger system comprises a first hydrogen high pressure refrigerant cooling passage configured to receive and cool a high pressure hydrogen supplemental refrigerant feed stream, thereby forming a cooled hydrogen supplemental refrigerant stream; h. A supplementary refrigerant expansion device having an inlet in fluid communication with the first hydrogen high-pressure refrigeration cooling channel, thereby generating an expanded hydrogen supplementary refrigerant flow having a pressure not less than the pressure of the cold box feed flow; as well as i. The heat exchanger system includes a high-pressure hydrogen refrigerant heating channel, which is connected to the outlet fluid of the supplemental refrigerant expansion device and is configured to receive an expanded hydrogen supplemental refrigerant flow, thereby providing cooling in the heat exchanger system and forming a high-pressure hydrogen product flow having a pressure higher than the pressure of the cold box feed flow.

2. The system according to claim 1, wherein: The heat exchanger system also includes a feed stream cooling channel, which is fluidly connected to the cold box feed pipeline and is configured to receive and cool the cold box feed stream to form a first adsorber feed stream. The heat exchanger system also includes a first adsorber, which is configured to receive the first adsorber feed stream to form a liquefier feed stream.

3. The system according to claim 2, wherein: The heat exchanger system includes a first heat exchanger having the feed stream cooling passage and a second heat exchanger having the liquefier cooling passage, and wherein the first and second heat exchangers are each separate and discrete heat exchanger devices.

4. The system of claim 1, further comprising a flow splitter in fluid communication with the cold box feed line and configured to split a fluid flow into a liquefier feed flow and a refrigerant flow.

5. The system according to claim 1, wherein: The product expansion device is configured to form a mixed-phase expanded product stream and further comprises: j. a product separator having a product separator vapor outlet and a product separator liquid outlet, the product separator being configured to receive the mixed-phase product stream from the product expansion device and to produce a liquid hydrogen product stream exiting the product separator through the product separator liquid outlet and a hydrogen vapor stream exiting the product separator through the product separator vapor outlet; k. The heat exchanger system comprises a first product separator vapor recirculation passage in fluid communication with the product separator vapor outlet, thereby providing cooling and forming a first recirculation stream in the heat exchanger system; l. a first recycle compressor having an inlet configured to receive a first recycle stream, thereby forming a compressed first recycle stream; The cold box feed stream comprises at least a compressed first recycle stream and a hydrogen feed stream.

6. The system according to claim 5, wherein: The heat exchanger system further comprises: i) a second liquefier cooling passage in fluid communication with the liquefier cooling passage and a product expansion device; ii) a second refrigerant cooling passage in fluid communication with the first refrigerant cooling passage and the first refrigerant expansion device; iii) a second refrigerant heating channel; And also includes: m. a second refrigerant expansion device configured to receive a first portion of the cooling refrigerant flow exiting the first refrigerant cooling passage, thereby forming a second expanded refrigerant flow; n. The second refrigerant cooling channel is configured to receive and cool a second portion of the cooling refrigerant flow; o. The second refrigerant heating passage is in fluid communication with the outlet of the second refrigerant expansion device, thereby providing cooling in the heat exchanger system; p. A second recirculation compressor having an inlet connected to the second refrigerant heating channel and the outlet fluid of the first recirculation compressor to form a compressed second recirculation flow, the second recirculation compressor having an outlet connected to the cold box feed pipeline fluid, and wherein the inlet or outlet of the second recirculation compressor is configured to receive a hydrogen feed flow, so that the second recirculation compressor receives the hydrogen feed flow or the cold box feed flow contains the hydrogen feed flow.

7. The system according to claim 6, wherein: The second refrigerant expansion device is a turbine.

8. The system according to claim 6 further includes a high-temperature hydrogen expander, which is configured to receive a portion of the cooling refrigerant flow leaving the first refrigerant cooling passage, so that a hydrogen expander refrigerant expansion flow is formed and directed to the first product separator vapor recirculation passage, the second refrigerant heating passage, or both the first product separator vapor recirculation passage and the second refrigerant heating passage of the heat exchanger system.

9. The system according to claim 5, wherein: The first refrigerant expansion device is configured so that the expanded refrigerant flow is a mixed phase, and also includes a refrigerant separator, which is configured to receive the expanded refrigerant flow and separate it into a vapor refrigerant flow and a liquid refrigerant flow, the refrigerant separator having a refrigerant separator vapor outlet and a refrigerant separator liquid outlet, and wherein the refrigerant separator vapor outlet is connected to the first compressor inlet fluid.

10. The system according to claim 5, wherein: The heat exchanger system further comprises: i) a product liquefier cooling passage in fluid communication with the liquefier cooling passage and a product expansion device; ii) a product vapor heating passage configured to receive and heat a hydrogen vapor stream from a product separator vapor outlet of the product separator.

11. The system according to claim 10, wherein: The heat exchanger system is configured to receive and heat the liquid stream from the refrigerant separator to form a mixed-phase hydrogen refrigerant stream, and return the mixed-phase hydrogen refrigerant stream to the refrigerant separator.

12. The system according to claim 10, wherein: The second liquefier cooling passage and the product liquefier cooling passage each contain an ortho-para conversion catalyst or are in fluid communication with one or more catalytic reactors.

13. The system according to claim 10, wherein: The heat exchanger system includes a product heat exchanger including the product liquefier cooling passage and a product vapor heating passage.

14. The system according to claim 13, wherein: The heat exchanger system includes a first heat exchanger configured to receive and cool the cold box feed stream and a second heat exchanger having the liquefier cooling passage and a refrigerant cooling passage, and the first, second and product heat exchangers are each a separate heat exchanger device.

15. The system of claim 1 further comprising a second adsorber configured to receive the cooled hydrogen supplemental refrigeration flow, and wherein: The heat exchanger system includes a second hydrogen high pressure refrigeration cooling passage in fluid communication with an outlet of a second adsorber and an inlet of a supplemental refrigerant expansion device.

16. The system of claim 1, wherein: The supplemental refrigerant expansion device is a turbine.

17. The system of claim 1, wherein: Each of the product expansion device and the refrigerant expansion device is a Joule-Thomson valve.

18. The system of claim 1, wherein: The liquefier cooling passages of the heat exchanger system contain an ortho-para conversion catalyst or are in fluid communication with one or more catalytic reactors.

19. The system of claim 1, wherein: The heat exchanger system includes a first supplemental refrigerant passage configured to receive a non-hydrogen supplemental refrigerant.

20. The system of claim 1, wherein: The cold box feed stream pressure is about 200-600 psig.

21. The system of claim 1, wherein: The cold box feed stream pressure is about 250-400 psig.

22. The system according to claim 1 further includes a first closed-loop compressor and a closed-loop expansion device, wherein the first closed-loop compressor has an inlet connected to the refrigerant heating channel fluid and an outlet connected to the refrigerant cooling channel fluid, and the closed-loop expansion device has an inlet connected to the refrigerant cooling channel fluid and an outlet connected to the refrigerant heating channel fluid.

23. The system of claim 22, wherein: The refrigerant includes helium or neon.

24. The system of claim 22, wherein: The heat exchanger system further comprises: i) a second liquefier cooling passage in fluid communication with the liquefier cooling passage and a product expansion device; ii) a second refrigerant cooling passage in fluid communication with the refrigerant cooling passage and the first refrigerant expansion device; iii) a second refrigerant heating channel; And also includes: j. a second refrigerant expansion device configured to receive a first portion of the cooling refrigerant flow exiting the refrigerant cooling passage to form a second expanded refrigerant flow; k. The second refrigerant cooling channel is configured to receive and cool a second portion of the cooling refrigerant flow; l. The first and second refrigerant heating passages are in fluid communication with the outlets of the first and second refrigerant expansion devices, thereby providing cooling in the heat exchanger system; m. The closed-loop compressor inlet is in fluid communication with the first and second refrigerant heating passages.

25. A method for liquefying a hydrogen feed stream comprising the steps of: a. receiving a cold box feed stream comprising at least a hydrogen feed stream into a heat exchanger system, wherein the cold box feed stream has a cold box feed stream pressure; b. cooling the liquefier feed stream including the cold box feed stream in a heat exchanger system to form a product stream; c. expanding the product stream to form an expanded product stream; d. cooling the refrigerant flow in the heat exchanger system to form a cooling refrigerant flow; e. expanding the cooled refrigerant stream to form a first expanded refrigerant stream; f. heating the first expanded refrigerant stream, thereby providing cooling in the heat exchanger system; g. cooling the high pressure hydrogen supplemental refrigerant feed stream in the heat exchanger system to form a cooled hydrogen supplemental refrigerant stream; h. expanding the cooled hydrogen supplementary refrigerant stream to form an expanded hydrogen supplementary refrigerant stream having a pressure not less than the cold box feed stream pressure; and i. Heating and expanding the make-up hydrogen refrigerant stream to provide cooling in the heat exchanger system and to form a high pressure hydrogen product stream at a pressure higher than the pressure of the cold box feed stream.

26. The method according to claim 25, wherein: Step c. comprises forming a mixed phase product stream, and further comprising the steps of: j. separating the mixed phase product stream into a liquid hydrogen product stream and a hydrogen vapor stream; k. heating the hydrogen vapor stream to provide cooling in a heat exchanger system and to form a first recycle stream; 1. Compressing the first recycle stream to form a compressed first recycle stream, and combining the compressed first recycle stream with the hydrogen feed stream to form a cold box feed stream.

27. The method according to claim 26, further comprising the steps of: m. The cooling refrigerant stream is divided into a liquefier feed stream and a refrigerant stream; o. dividing the refrigerant stream into a first portion and a second portion, wherein the first portion is expanded to form a first expanded refrigerant stream; p. expanding a second portion of the refrigerant stream to form a second expanded refrigerant stream; q. heating the second expanded refrigerant stream to provide cooling in the heat exchange system and form a second recirculation stream; r. Combining the second recycle stream with the compressed first recycle stream and the feed gas stream to form a cold box feed stream.

28. The method according to claim 25, wherein: The liquefier feed stream comprises about 20-25% of a purified, cooled cold box feed stream.

29. The method according to claim 25, wherein: The cold box feed stream pressure is about 200-600 psig.

30. The method of claim 25, wherein: The cold box feed stream pressure is about 250-400 psig.

31. The method of claim 25 further comprising the step of converting a portion of the liquefier feed stream from orthohydrogen to parahydrogen.

32. The method of claim 25 further comprising the step of cooling and purifying the cold box feed stream to form the liquefier feed stream.

33. The method of claim 25, wherein: The refrigerant stream includes hydrogen.

34. The method of claim 25, wherein: Step f. produces a heated refrigerant stream, and further comprises the step of compressing the heated refrigerant stream to provide the cooled refrigerant stream in step d.

35. The method of claim 34, wherein: The refrigerant includes helium.

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