TW202407272A - System and method for cooling fluids containing hydrogen or helium - Google Patents

Abstract

A system for cooling a feed stream including hydrogen or helium with a mixed refrigerant includes a pre-cooling heat exchanger. A compression system has an inlet in fluid communication with the pre-cooling heat exchanger and receives and increases a pressure of a refrigerant vapor stream including hydrogen and/or helium mixed with at least one other refrigerant such that the molecular weight of the mixture is greater than 6 kg/kgmol. The compression system has an outlet in fluid communication with the pre-cooling heat exchanger. A first refrigerant separation device receives fluid from the pre-cooling heat exchanger and has a liquid outlet in fluid communication with the pre-cooling heat exchanger and a vapor outlet. A refrigerant purifier has a purifier inlet in fluid communication with the vapor outlet of the first refrigerant separation device and an outlet in fluid communication with the pre-cooling heat exchanger.

Description

Systems and methods for cooling fluids containing hydrogen or helium

This application claims the benefit of U.S. Provisional Application No. 63/342338, filed on May 16, 2022, the contents of which are incorporated herein by reference.

The present invention relates generally to systems and methods for liquefying gases, and more particularly to systems and methods for liquefying fluids containing hydrogen or helium.

Industrial gases such as natural gas or hydrogen are advantageously stored or transported in the liquid state because they occupy a much smaller volume (eg 1/600 of a gas for natural gas and 1/848 for hydrogen). Liquefied gases are often evaporated back to the gaseous state for use on site or in a system.

Gaseous hydrogen is converted to liquid hydrogen by cooling below about 20-25K. Typical cooling processes utilize large amounts of energy and are very expensive in terms of equipment costs. The process can include multiple refrigeration cycles and involve multiple stages of gas compression.

Prior art hydrogen liquefaction systems typically use reciprocating or screw compressors. Systems and/or processes that can use dynamic compressors for hydrogen liquefaction are desirable. Dynamic compressors are more reliable than reciprocating compressors and more efficient than screw compressors. Dynamic compressors include those that do not require positive displacement, such as centrifugal, radial, or axial compressors. In prior art liquefaction systems, dynamic compressors are less suitable for low molecular weight gases (<6 kg/kgmol) such as hydrogen or helium.

An example of a prior art hydrogen liquefaction system is described in U.S. Patent 3,992,167 to Beddome, which describes a process in which propane is added to the hydrogen such that the compressed refrigerant circulation stream is 33% propane and 67% hydrogen. . Additional components with higher molecular weights than propane are desirable to increase the efficiency of the process by allowing more compression power to be used for the hydrogen or helium and to simplify separation of the additional components from the hydrogen or helium. The process of Beddome's '167 patent also contains a single adsorption purification unit for delivering the hydrogen stream to the coldest part of the process. This results in uncondensed hydrocarbons being purged from the process when the adsorbent is regenerated. Processes with near-zero hydrocarbon emissions are desirable and may be particularly important under environmental regulations.

US Patent 5,579,655 to Grenier describes a prior art process in which small amounts of saturated C2, C3, optional C4 and C5 hydrocarbons are mixed with hydrogen to form a mixed refrigerant. The process consists of a separate hydrogen feed stream that is liquefied and not mixed with the mixed refrigerant stream, thus requiring dual cryogenic purifiers at 75-80K. Purification of hydrogen from small amounts of mixed refrigerant components is more complex due to the inclusion of ethane in the mixed refrigerant and requires a liquid propane scrubber for separation, resulting in the need for continuous hydrocarbon make-up to compensate for hydrocarbon losses to the environment. Liquid propane scrubbers also add cost and complexity to the process.

US Patent 10928127 to Cardella et al. describes a method for hydrogen liquefaction using mixed refrigerants. The refrigerant mixtures mentioned contain nitrogen, neon, argon and hydrocarbons, but not hydrogen or helium. The refrigerant mixtures of the invention described here must contain hydrogen or helium. Additionally, the method described in US Pat. No. 1,0928,127 also uses a substantially pure hydrogen gas stream, which requires a positive displacement compressor as a separate refrigerant in addition to the mixed refrigerant. The process described in US Patent 10928127 does not provide pre-cooling of the hydrogen feed below 85K. This increases the refrigeration load on the hydrogen refrigerant compared to standard methods using liquid nitrogen pre-cooling or the invention described herein.

U.S. Patent 3,490,245 to Muenger describes a heat exchanger that removes trace impurities, including carbon dioxide, hydrogen sulfide, carbon disulfide, and carbonyl sulfide, from an ammonia synthesis feed by freezing them from the stream being purified. It has been demonstrated that this type of heat exchanger can be used in place of adsorption systems to remove impurities that would otherwise freeze in a cold box heat exchanger. A freezing device is defined as a device that removes one or more impurities from a mixed stream by selectively freezing specific one or more components. The device described in US Patent 3,490,245 is an example of a freezing device.

Various aspects of the subject matter may be implemented separately or together in the methods, apparatus, 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 preclude the use of these aspects alone or separate claims for these aspects or as set forth in the attached claims. combination.

In one aspect, a system for cooling a feed stream including hydrogen or helium with a mixed refrigerant includes a precooling heat exchanger having a feed stream cooling channel, a first refrigerant cooling channel, a second refrigerant cooling channel, and Refrigerant heating channel. The compression system has an inlet in fluid communication with the refrigerant warming passage and is configured to receive and increase the pressure of a refrigerant vapor stream of hydrogen and/or helium mixed with at least one other refrigerant such that the mixture has a molecular weight greater than 6 kg/kg mol. The compression system has an outlet in fluid communication with the first refrigerant cooling passage. The first refrigerant separation device is configured to receive fluid from the first refrigerant cooling channel in the pre-cooling heat exchanger. The first refrigeration separation device has a liquid outlet and a steam outlet in fluid communication with the refrigerant heating channel.

The refrigerant purifier has a purifier inlet in fluid communication with the vapor outlet of the first refrigerant separation device and an outlet in fluid communication with the second refrigerant cooling passage. The second refrigerant cooling channel has an outlet in fluid communication with the refrigerant warming channel.

In another aspect, a method of liquefying a feed stream comprising hydrogen or helium includes the steps of mixing the hydrogen or helium refrigerant with at least one additional refrigerant component having a molecular weight greater than that of the hydrogen or helium to form a refrigerant having a molecular weight of at least 6 kg/kg mol the mixed refrigerant; compressing the mixed refrigerant using a dynamic compressor; separating at least one additional refrigerant component from the hydrogen or helium refrigerant at a temperature of 75K or higher to obtain the remaining hydrogen or helium refrigerant; and The remaining hydrogen or helium refrigerant is used to cool the hydrogen or helium feed stream to produce a liquid hydrogen or helium product from the feed stream.

In yet another aspect, a system for cooling a cryogenic fluid feed stream containing hydrogen or helium with a mixed refrigerant includes a pre-cooling heat exchanger having a pre-cooled feed stream cooling channel, a low pressure refrigerant warming channel, an intermediate pressure A refrigerant heating channel, a first refrigerant cooling channel and a second refrigerant cooling channel. The mixed gas compressor is configured to receive the mixed refrigerant vapor flow from the low pressure refrigerant warming passage. The mixed gas aftercooler is in fluid communication with the mixed gas compressor. The mixing device has a first inlet, a second inlet and a mixing device vapor outlet in fluid communication with the mixed gas aftercooler. The second inlet is configured to receive a flow of mixed refrigerant vapor from the intermediate pressure refrigerant warming passage. The first interstage compressor is in fluid communication with the mixing device vapor outlet. The first interstage aftercooler is in fluid communication with the first interstage compressor. The high-pressure accumulator is in fluid communication with the first interstage aftercooler and has a high-pressure accumulator vapor outlet and a high-pressure accumulator liquid outlet. The high-pressure accumulator steam outlet is in fluid communication with the first refrigerant cooling channel, and the high-pressure accumulator liquid outlet is in fluid communication with the medium-pressure refrigerant heating channel. The first refrigerant separation device is in fluid communication with the first refrigerant cooling channel and has a first refrigerant separation device liquid outlet in fluid communication with the low-pressure refrigerant warming channel and a first refrigeration outlet in fluid communication with the second refrigerant cooling channel. Steam outlet of agent separation device. The second refrigerant separation device is in fluid communication with the second refrigerant cooling passage and has a second refrigerant separation device liquid outlet and a second refrigerant separation device vapor outlet in fluid communication with the low pressure refrigerant warming passage. The refrigerant purifier has a purifier inlet and a purifier outlet in fluid communication with the steam outlet of the second refrigerant separation device, wherein the purifier outlet is in fluid communication with the low-pressure refrigerant warming channel and the medium-pressure refrigerant warming channel.

It should be noted here that lines, conduits, ducts, channels and similar structures and the corresponding flows are sometimes designated by the same element numbers as shown in the figures.

Furthermore, as used herein, and as is known in the art, a heat exchanger is a device or area within a device in which indirect heat occurs between two or more streams of different temperatures or between the streams and the environment. Exchange. Furthermore, all heat exchangers mentioned herein may be combined into one or more heat exchanger devices, or may each be a separate heat exchanger device. As used herein, the terms "communicate" and the like generally refer to fluid communication unless otherwise stated. And although two fluids in communication can exchange heat when mixed, this exchange is not the same as heat exchange in a heat exchanger, although such exchange can occur in a heat exchanger.

As used herein, the terms "high," "medium," "warm," "cold" and the like are relative to comparable flows, as is customary in the art.

By way of non-limiting example only, any tower mentioned in the following description may be a spray tower, a packed tower, a plate tower and/or any combination thereof.

Reference numbers introduced in the specification in connection with the figures may be reused in one or more subsequent figures for a shared element or component without additional description in the specification to provide context for other features.

In the claims, letters are used to identify the claimed steps (eg a, b and c). These letters are used to aid reference to method steps and are not intended to indicate the order in which the claimed steps should be performed, unless and only to the extent such order is specifically recited in the claim.

Embodiments of the disclosure described below provide methods and apparatus for liquefying hydrogen or helium using a refrigeration cycle in which the circulating fluid primarily includes hydrogen or helium and an optional closed supplemental refrigerant refrigeration cycle. The primary refrigeration cycle fluid is a mixture containing hydrogen or helium and at least one additional component with a higher molecular weight and a higher boiling point, which mixture is compressed outside the cold box and used to provide the hydrogen or helium feed stream in the cold box Cool. Removing one or more from the hydrogen-rich or helium-rich refrigerant stream in the cold box by a series of preferential partial condensation steps and adsorption and/or freezing and/or distillation at temperatures below ambient temperature and above about 75 K Various additional components. The removed components provide cooling to the cooling box as they are flashed to low pressure, reheated, and recycled back to a point in the compression train. Including controlled direct heat and mass transfer process steps between hydrogen or helium and one or more additional components in at least one interstage compression drum operating as a direct contact mixing vessel, providing simultaneous heat and mass transfer quality, ensuring evaporation of high molecular weight components and control of the composition, molecular weight and thermal properties of the mixed refrigerant stream in all cases. The remaining cryogenically purified hydrogen or helium is used as the primary refrigerant at temperatures below about 75-80K.

Increasing the molecular weight of a compressed hydrogen- or helium-containing stream by mixing in other components that are subsequently removed allows the use of dynamic compressors in place of less reliable reciprocating compressors in the compression process of mixed refrigerants.

Furthermore, the use of higher molecular weight components than in the prior art in the examples described below improves compressor performance while maintaining a relatively high hydrogen concentration in the mixture. The use of fluorinated hydrocarbons increases the molecular weight of the added component, which reduces the amount required to increase the molecular weight of the mixture, thereby increasing the hydrogen or helium concentration in the mixture.

The embodiments disclosed below reduce the power required for the supplemental refrigerant precooling cycle by utilizing the supplemental refrigeration load provided by the higher molecular weight components. This supplemental cooling load occurs primarily above about 190K. These improvements increase the overall efficiency of the precooling process. The excess supplemental refrigeration load supplied can exceed the needs of the hydrogen/supplemental refrigerant precooling system, and this excess load can provide refrigeration for other processes or systems.

The examples disclosed below also use refrigerant mixtures that do not contain hydrocarbons that boil at temperatures below about 190K. The removal of ethane and ethylene from the mixtures proposed in the prior art significantly simplifies and improves the separation of hydrocarbons from the hydrogen or helium stream before it is fed to the cold end process. The description of the figures refers to the case where hydrogen is the feed stream and the material to be liquefied. If helium is used, there is no positive secondary conversion catalyst and the final temperature is lower, but the description generally applies.

In one embodiment, as shown in Figure 1, the high pressure hydrogen feed 101 at about 14-26 bar and near ambient temperature is cooled to about 77-80 K in the pre-cooling heat exchanger 1 and used as the pre-cooled hydrogen feed Material 102 left. As is known in the art, the pre-cooling heat exchanger 1 is located inside the insulated cold box 7 . The pre-cooling heat exchanger 1 may be filled with a normal-para-conversion catalyst 2 in the hydrogen cooling channel to promote the conversion of a portion of the high-pressure hydrogen feed 101 from normal hydrogen to para-hydrogen. The pre-cooled hydrogen feed 102 is sent to an adsorption-based cryogenic purifier (51, shown in Figure 2) similar to the second refrigerant purifier 23, and hydrogen liquefaction processes in which a majority of the hydrogen is liquefied are well known in the art (an example is shown in Figure 2). A small portion of the precooled hydrogen feed is returned to precooling heat exchanger 1 as cold hydrogen recycle stream 103 .

The cold hydrogen recycle stream 103 is warmed in the pre-cooling heat exchanger 1 to provide cooling to the high pressure hydrogen feed 101 . The cold hydrogen recirculation will be at a lower pressure than the high pressure hydrogen feed 101 . This stream may optionally be passed through the normal secondary reforming catalyst 3 to take advantage of the additional cooling capacity available in the reforming. The cold hydrogen recycle stream 103 exits the precooling heat exchanger 1 as a warm hydrogen recycle stream 104 which can be compressed and returned to the process as part of the high pressure hydrogen feed 101 .

In many cases, an optional high-pressure supplemental refrigerant such as nitrogen 111 is cooled in the precooling heat exchanger 1 to form a cold high-pressure supplemental refrigerant stream 112 , which is expanded in the supplemental refrigerant expander 4 to form a cold Supplemental refrigerant flow 113. The cold supplemental refrigerant stream 113 provides cooling to the pre-cooling heat exchanger 1 and exits as a warm low pressure supplemental refrigerant stream 114 which is compressed in the supplemental refrigerant compressor 5 to form a hot compressed supplemental refrigerant. Stream 115 , which is cooled in the supplemental refrigerant compressor aftercooler 6 to form a high pressure supplemental refrigerant feed 111 . The supplementary refrigerant compressor 5 and the aftercooler 6 can consist of more than one stage, depending on the required pressure rise. Likewise, the supplementary refrigerant expander 4 can also be composed of more than one stage. Alternatively, the loop can be enhanced to include a more efficient scheme, such as that shown in Figure 3.

A low-pressure gas mixture 121 consisting of hydrogen and/or helium and at least one other substance with a higher molecular weight and a boiling point above 80 K is compressed in the first mixed gas compressor 11 and in the first compressor aftercooler 12 is cooled to form a first medium pressure mixture 122 that can be sent to the mixing vessel 13 . The first mixed gas compressor 11 may be a single-stage compressor, a compressor with more than one stage, or the lowest pressure stage of a multi-stage compressor. The mixing vessel 13 is designed to operate with or without liquid level and contains sprayers and/or heating coils, packing or other devices to enhance direct contact and heat and mass transfer between the inlet streams. Examples of these other substances include hydrocarbons, halogenated hydrocarbons, perfluorocarbons, neon, and other refrigerants. The second mixture 123 leaves the mixing vessel 13 and is compressed in the second mixed gas compressor 14 and cooled in the second compressor after-cooler 15 to form a second medium-pressure mixture 124, which is fed to the second A phase separator or interstage separation device 16 designed to remove any small amounts of liquid that may form. The second mixed gas compressor 14 may be a single-stage compressor, a compressor with more than one stage, or one or more stages of a multi-stage compressor operating at a higher pressure than the first mixed gas compressor. Controlled operation of the heat input of the mixing vessel 13 maximizes the amount of higher molecular weight components in the second mixture 123 by allowing the mixture to operate at or near its saturation or dew point conditions. This increases the molecular weight of the second mixture and increases its ability to be compressed. The third mixture 125 leaves the interstage separation device 16 and is compressed in the third mixed gas compressor 17 and cooled in the third compressor aftercooler 18 to form a high-pressure mixture 126 which is fed to the second Phase separator or high pressure accumulator19. The third compressor may be a single-stage compressor, a compressor with more than one stage, or one or more stages of a multi-stage compressor operating at a higher pressure than the second compressor. As shown in FIG. 1 , in all the following embodiments, the first, second and third mixed gas compressors 11 , 14 and 17 are located outside the cold box 7 .

The first liquid 160 exits the bottom of the interstage separation device 16 and can be discharged through the first phase separator valve 41 to form a low pressure first liquid 161 . The second liquid 162 , which mainly contains the high molecular weight components of the original mixture, leaves the bottom of the high-pressure accumulator 19 and can be discharged through the second phase separation valve 42 to form a low-pressure second liquid 163 and combine with the low-pressure first liquid 161 Mix to form a low pressure mixed liquid 164.

The low pressure mixed liquid 164 may be distributed in four different streams, namely mixing vessel recirculation stream 170, mixing vessel refrigeration feed 166, low pressure gas mixture vessel refrigeration feed 167 and low pressure gas mixture vessel recirculation stream 172. The mixing vessel recycle stream 170 is expanded through the mixing vessel valve 43 to form a low pressure mixing vessel recycle stream 171 , which is returned to the mixing vessel 13 . Mixing vessel refrigeration feed 166 is expanded by mixing vessel refrigeration expansion device 45 (eg, valve) to form cooling mixing vessel refrigerant 169 , which provides cooling to precooling heat exchanger 1 and back to mixing vessel 13 . A portion of the cooling mixing vessel refrigerant 174 may be conveyed as a separate stream through the precooling heat exchanger 1 such that it exits the precooling heat exchanger 1 as a two-phase flow. This reduces temperature differences in the heat exchanger and increases efficiency. The low pressure gas mixture vessel refrigeration feed 167 is expanded by the low pressure mixture vessel refrigeration expansion device 46 (eg, a valve) to form a cooling low pressure gas mixture vessel refrigerant 168 that provides cooling to the precooling heat exchanger 1 and returns to the low pressure gas mixture vessel twenty four. The low pressure gas mixture container recycle stream 172 is expanded through the low pressure gas mixture container valve 44 to form a reduced pressure gas mixture container recycle stream 173 which is returned to the low pressure gas mixture container 24 . The accumulated liquid 175 from the mixing container 13 may be pressurized using the mixing container pump 49 to form a pressurized accumulated liquid 176 and mixed with the first liquid 160 or the second liquid 162 . The pump 49 and mixing vessel 13 allow the molecular weight of the compressor feed stream to be controlled and maintained at a relatively high level. Alternatively (not shown), the accumulated liquid 175 may be mixed with the low pressure gas mixture vessel feed 143 and supplied to the low pressure gas mixture vessel 24 .

The second phase separator vapor 127 leaves the top of the high-pressure accumulator 19 and is cooled in the pre-cooling heat exchanger 1 to form a first cooling mixed refrigerant 128 which is fed to the first mixed refrigerant separator 20 . The first mixed refrigerant vapor 129 leaves the top of the first mixed refrigerant separator 20 and returns to the pre-cooling heat exchanger 1 where it is further cooled to form a second cooled mixed refrigerant stream 130 which is fed to The second mixed refrigerant separator 21. The second mixed refrigerant vapor 131 leaves the top of the second mixed refrigerant separator 21 and is purified in the mixed refrigerant purifier 22, which removes substantially all mixture components with boiling points above 80K. The mixed refrigerant purifier 22 may be an adsorption system that preferentially removes mixture components with boiling points above 80K. An adsorption system usually consists of more than one adsorption bed, such that one or more adsorption beds are regenerable while another adsorption bed or beds are active. Freezing units, distillation columns or other purification methods can also be used as refrigerant purifiers. Freezing units will require similar regeneration. The mixed refrigerant purifier regeneration feed 191 is used to purge trapped impurities out of the mixed refrigerant purifier 22 to regenerate them for a new feed step. Purifier regeneration feeds typically consist of nitrogen, hydrogen, helium, or mixtures thereof. Regeneration is typically performed at lower pressures and higher temperatures than the purifier's typical operating pressures and temperatures. When there are at least two mixed refrigerant purifiers, traces of heavy refrigerant components in the first purifier can be selectively removed without removing lighter impurities introduced with the feed, such as nitrogen or argon. The impurity-containing regeneration stream 192 may be recycled to the inlet of the first mixed gas compressor or low pressure gas mixing vessel 24 . This allows the system to recover trace amounts of other substances in the mixed refrigerant removed in the refrigerant purifier 22 . Where the hydrocarbon is used as another substance, this ensures essentially complete recovery of the hydrocarbon and essentially zero hydrocarbon emissions, unlike processes in the prior art.

The purified hydrogen/helium stream 132 leaves the mixed refrigerant purifier 22 and returns to the pre-cooling heat exchanger 1 where it is further cooled and leaves as cooling refrigerant 133 which is processed in the second refrigerant purifier is further purified in 23, which purifier is similar to mixed refrigerant purifier 22, except that the second refrigerant purifier is designed to remove lighter impurities, including nitrogen and argon, while the mixed refrigerant purifier is designed to remove higher boiling point impurities. Higher molecular weight substances above 80K. The low temperature refrigerant 134 exits the second refrigerant purifier 23 and is fed to the hydrogen liquefaction process. Similar to the mixed refrigerant purifier 22 , the second refrigerant purifier regeneration feed 193 is used to regenerate the second refrigerant purifier 23 . All or a portion of the second impurity-containing regeneration stream 194 may be recycled to a crude hydrogen purifier (not shown) or vented, since nitrogen, argon, and other light impurities can accumulate to unacceptably high concentrations if never removed. Alternatively, a portion of the regeneration flow can be recycled to the compressor inlet, depending on its pressure. A crude hydrogen purifier is a device located upstream of the high pressure hydrogen feed 101 and may be, for example, a pressure swing adsorption system that separates hydrogen from other components in the mixture produced by a hydrogen generation system such as a reformer or electrolyzer. . In an alternative, the two refrigerant purifiers can be combined into a single unit. In this case, the regeneration stream can be recycled to the crude hydrogen purifier, or a portion of the regeneration stream can be recycled to the compressor inlet, depending on its pressure.

The first mixed refrigerant liquid 181 exits the bottom of the first mixed refrigerant separator 20 and expands in the first mixed refrigerant liquid expansion device 47 (eg, a valve) to cool the flow and reduce its pressure, thereby forming a cooling low pressure First mixed refrigerant liquid stream 182 . The second mixed refrigerant liquid 184 exits the bottom of the second mixed refrigerant separator 21 and expands in the second mixed refrigerant liquid expansion device 48 (eg, a valve) to cool the flow and reduce its pressure, thereby forming a cooling low pressure Second mixed refrigerant liquid stream 185 . The cooled low pressure first mixed refrigerant liquid stream 182 and the cooled low pressure second mixed refrigerant liquid stream 185 combine to form a low pressure mixed refrigerant recirculation stream 183 which enters the precooling heat exchanger 1 to provide cooling.

Low pressure refrigerant 141 is recycled from the hydrogen liquefaction process and enters the pre-cooling heat exchanger 1 to provide cooling. The low-pressure refrigerant 141 is mixed in the pre-cooling heat exchanger 1 with the cooling low-pressure gas mixture container refrigerant 168 and the low-pressure mixed refrigerant recirculation stream 183 and leaves as warm mixed refrigerant 142 which reacts with the reduced pressure The gas mixture vessel recycle streams 173 combine to produce a low pressure gas mixture vessel feed 143 into the low pressure gas mixture vessel 24 .

The medium pressure refrigerant 151 leaves the hydrogen liquefaction process and enters the pre-cooling heat exchanger 1 to provide cooling. The intermediate pressure refrigerant 151 is mixed with the cooling mixing vessel refrigerant 169 in the precooling heat exchanger 1 and exits as mixing vessel recirculation feed 152 entering the mixing vessel 13 .

Figure 2 illustrates an example cold end process for producing liquid hydrogen product. There are many variations of this configuration known in the art that may be suitable for the techniques of the present disclosure. The example shown in Figure 2 is just one of many possible options. The cold end configuration chosen has no significant impact on the technology of the present disclosure or its use.

Precooled hydrogen feed 102 from Figure 1 enters hydrogen feed purifier 51, similar to the second refrigerant purifier in Figure 1 . The hydrogen feed purifier removes any impurities in the hydrogen feed before the stream is further cooled. These impurities typically consist primarily of nitrogen and argon with other trace components that may have been frozen in the cryogenic heat exchanger. The purified hydrogen feed 201 exits the hydrogen feed purifier 51 and enters the first cold heat exchanger 53 where it is cooled and a portion of the orthohydrogen is converted to secondary hydrogen on the reforming catalyst located in the first cold heat exchanger catalyst channel 52 hydrogen to produce a second purified hydrogen feed 202.

The second purified hydrogen feed 202 exits the first cold heat exchanger 53 and enters the second cold heat exchanger 55, where a portion of the orthohydrogen is converted to parahydrogen on the reforming catalyst located in the second cold heat exchanger catalyst channel 54 to produce Third purified hydrogen feed 203. The third purified hydrogen feed 203 exits the second cold heat exchanger 55 and enters the third cold heat exchanger 57, where a portion of the orthohydrogen is converted to parahydrogen on the reforming catalyst located in the third cold heat exchanger catalyst channel 56 to produce a third cold heat exchanger 57. Four purified hydrogen feed 204. The fourth purified hydrogen feed 204 exits the third cold heat exchanger 57 and enters the fourth cold heat exchanger 59, where a portion of the orthohydrogen is converted to parahydrogen on the reforming catalyst located in the fourth cold heat exchanger catalyst channel 58 to produce a third cold heat exchanger. 5. Purified hydrogen feed 205. If required, the cold and heat exchangers can be combined into one, two or three heat exchangers with side feeds and outlets. In most cases, these heat exchangers will be combined to reduce capital costs, piping, connections and cold box volume. The selected combination of heat exchangers does not affect the technology of the invention or its use.

The fifth purified hydrogen feed 205 is expanded through an expansion device such as hydrogen product expansion valve 60 to form a two-phase hydrogen feed 206 which is separated in hydrogen product separator 61 . Liquid hydrogen product 207 is discharged from the bottom of the separator. Cold hydrogen vapor 208 is removed from the top of the separator and supplied to the fourth cold heat exchanger 59, the third cold heat exchanger 57, the second cold heat exchanger 55 and the first cold heat exchanger 53, where it is heated to Provides cooling of the hydrogen feed. The cold hydrogen vapor 208 forms first warm hydrogen vapor flow 209, second warm hydrogen vapor flow 210 and third warm hydrogen vapor after leaving the fourth heat exchanger 59, the third heat exchanger 57 and the second heat exchanger 55 respectively. Stream 211 and exits the heat exchanger as cold hydrogen recycle stream 103, as shown in Figures 1 and 2.

The low-temperature refrigerant 134 leaves the second refrigerant purifier 23 shown in Fig. 1, is supplied to the first cold and heat exchanger 53 in Fig. 2, and leaves as the first hydrogen refrigerant 221, which is The flow is split between an expander feed 222 and a second cold heat exchanger refrigerant feed 223. The first expander feed 222 is expanded in the first hydrogen expander 62 to produce a first hydrogen expander product 224 which is used to provide cooling in the second cold heat exchanger 55 and exits as a warm first hydrogen expander product 225 , and leaves the first heat and cold exchanger 53 before exiting as intermediate pressure refrigerant 151, as shown in Figures 1 and 2 . The second heat and cold exchanger refrigerant feed 223 is supplied to the second heat and cold exchanger 55 and exits as a second hydrogen refrigerant 226 which is exchanged between the second expander feed 227 and the third heat and cold exchanger 55 . The refrigerant feed 231 of the device is divided. The second expander feed 227 is expanded in the second hydrogen expander 63 to produce a second hydrogen expander product 228 which is used to provide cooling in the third cold heat exchanger 57 .

The third heat and cold exchanger refrigerant feed 231 is supplied to the third heat and cold exchanger 57 and exits as a third hydrogen refrigerant 232 which is supplied to the hydrogen refrigerant expansion valve 64 to form two Phase hydrogen refrigerant 233 is separated in the refrigerant separator 65 . Liquid refrigerant 237 is removed from the bottom of the separator and provided with cooling in the fourth heat and cold exchanger 59 where it is at least partially evaporated and returned to the refrigerant separator as a second two-phase refrigerant 238 . Cold hydrogen refrigerant vapor 234 is removed from the top of refrigerant separator 65, mixed with second hydrogen expander product 228 to form cold refrigerant feed 229, and supplied to third cold heat exchanger 57 as a second cold The refrigerant feed 235 exits the second cold heat exchanger 55 and exits the first cold heat exchanger 53 as a third cold refrigerant feed 236 where it is warmed to provide cooling to the hydrogen feed. The cold refrigerant supply 229 exits the cold heat exchanger as low pressure refrigerant 141 as shown in Figures 1 and 2. The heat exchangers 53, 55, 57 and 59 of Figure 2 may be located within the cold box 7 of Figure 1, or they may be located within their own cold box.

Alternatives to the process shown in Figure 2 include processes in which the expanders are operated in series rather than in parallel, or in which the heat exchangers are combined in any of a single possible configuration. If helium is used as the refrigerant and the process is used to liquefy hydrogen, there is no need to produce liquid helium and refrigerant separator 65 is not necessary because there is no liquid refrigerant 237. None of these changes affect the practice and advantages of the techniques described here.

Figure 3 shows another example warm end process with an improved supplemental refrigerant cooling system. The supplemental refrigerant may be nitrogen or another refrigerant with appropriate refrigeration properties for the desired cycle. All numbers represent essentially the same streams or devices as shown in Figure 1 and described previously. This alternative includes a modified supplemental refrigerant refrigeration circuit, with pre-cooled hydrogen feed 102 mixed with cooling refrigerant 133 and fed to a single hydrogen purifier 33 to produce a combined pre-cooled hydrogen stream 135 . Other processes include the use of modified supplemental refrigerant refrigeration circuits or mixing of cold streams, but not other processes.

The advantage of combining precooled hydrogen feed 102 and purified hydrogen stream 132 to form combined purifier feed 135 is that only one cryogenic purifier is required for both streams and produces a combined purifier product 136 . The disadvantage is that both streams must be at the same pressure, and the refrigerant and feed must be the same material. For example, if helium refrigerant is used to liquefy hydrogen, these streams cannot be combined. The benefit of reducing capital costs by eliminating the second purifier and subsequently shrinking the cold box can be compared with the cost of reduced operational flexibility to determine whether mixing streams is beneficial. In this case, as shown in Figure 2, a portion of the combined purifier product 136 is diverted to form purified hydrogen feed 201, while the remaining portion becomes cryogenic refrigerant 134 as shown in Figure 2.

The improved supplemental refrigerant refrigeration circuit includes a cooling high-pressure supplemental refrigerant flow 211 which is fed to the precooling heat exchanger 1 . The first supplemental refrigerant portion 212 is taken from the cooled high pressure supplemental refrigerant stream 211 and expanded in the first supplemental refrigerant expander 4 to form a first supplemental refrigerant 213 which is returned to the pre-cooling heat exchanger 1 where There it provides refrigeration. The second supplemental refrigerant portion 214 is taken from the cooled high-pressure supplemental refrigerant stream 211 at a lower temperature than the first portion 212 and expanded in the second supplemental refrigerant expander 5 to form a second supplemental refrigerant 215 which is returned to the pre-cooling Heat exchanger 1, where it provides refrigeration. The remaining makeup refrigerant 217 cooling the high pressure makeup refrigerant stream 211 leaves the pre-cooling heat exchanger 1 at a minimum temperature and expands in the makeup refrigerant expansion valve 6 to form cold makeup refrigerant 218 which is returned to the pre-cooling heat exchanger Unit 1, where it provides refrigeration. Cold supplemental refrigerant 218 is warmed in the pre-cooling heat exchanger 1 to create a warmed low pressure supplemental refrigerant recirculation 219 which is compressed in the first supplemental refrigerant compressor 7 to form a compressed first supplemental refrigeration 220 and is cooled in the first supplemental refrigerant compressor aftercooler 8 to create a first medium pressure supplemental refrigerant recirculation 221 . The first supplementary refrigerant 213 and the second supplementary refrigerant 215 are combined in the precooling heat exchanger 1 and are heated to produce a warmed medium pressure supplementary refrigerant recirculation 216 which is recirculated with the first medium pressure supplementary refrigerant. Cycles 221 combine to produce medium pressure makeup refrigerant 222 . Medium-pressure supplemental refrigerant 222 is compressed in the second supplemental refrigerant compressor 9 to form compressed medium-pressure supplemental refrigerant 223, and is cooled in the second supplemental refrigerant compressor aftercooler 10 to produce cooling high-pressure supplemental refrigeration. Agent flow 211. The first supplemental refrigerant compressor and/or the second supplemental refrigerant compressor may be a single-stage compressor, a compressor with more than one stage, or one or more stages of a multi-stage compressor such that the second supplemental refrigerant compressor Operate at a higher pressure than the first supplemental refrigerant compressor.

In an alternative, a portion of the cooled pressurized first supplemental refrigerant portion 251 of the first portion 212 of the high pressure supplemental refrigerant flow 211 is output to the external process 31 for use as refrigerant. The makeup refrigerant is then returned to the process as makeup refrigerant return stream 252 . The external process 31 may be any process capable of utilizing additional refrigeration between the temperature of the first supplemental refrigerant portion 212 and the ambient temperature. Another alternative is that a portion of the first supplemental refrigerant 213 can be exported. This has the advantage of being at a lower temperature and not requiring additional expansion devices in the external process 31 , but also having lower pressure and less driving force to move through the external process 31 .

In the process of Figure 4, 165 is fed to the pre-cooling heat exchanger 1 before being expanded in the mixing vessel refrigeration expansion device 45. This allows the cooling mixing vessel refrigerant 169 to be at a lower temperature than possible and provides additional cooling to the process. Another variation shown in Figure 4 is for the first mixed refrigerant liquid 181 to be split and expanded in either the first mixed refrigerant liquid expansion device 47B or the second mixed refrigerant liquid expansion device 47A (eg a valve) to cool the flow and Its pressure is reduced, thereby forming a cooled low-pressure first mixed refrigerant liquid stream 182 or a second low-pressure mixed refrigerant recirculation flow 183A, which has a higher pressure than the cooled low-pressure first mixed refrigerant liquid stream 182 . The cooling low pressure first mixed refrigerant liquid stream 182 is combined with the cooling low pressure second mixed refrigerant liquid stream 185 to form a cold mixed refrigerant recirculation stream 183B, which is mixed with the low pressure refrigerant 141 entering the precooling heat exchanger 1 to form the The process provides refrigeration.

Other potential configurations in which the disclosed technology can be practiced will be apparent to those skilled in the art.

Example Referring to Figure 5, the following example illustrates one possible way of practicing the invention. The process produces 15 tons/day (625 kg/hour) of liquid hydrogen product. The conditions and composition of the selected streams are shown in Table 1.

The refrigerant mixture chosen for this example is a mixture of hydrogen, propane, and isopentane. The molecular weight of the low pressure gas mixture 121 is ~28kg/kgmol and the molecular weight of the second mixture 123 is ~11kg/kgmol. These are high enough to use dynamic compressors, which are more reliable than typical positive displacement compressors for hydrogen, which has a molecular weight of ~2kg/kgmol. Other hydrocarbons or other refrigerants may be used, including halogenated hydrocarbons and partially halogenated hydrocarbons. Other ingredients or proportions may also be used. Due to the conditions and refrigerant makeup in the example, there is no flow in streams 160, 167, 170, 172 or 175 shown in Figure 4 and therefore these streams are not shown in Figure 5.

High pressure hydrogen feed 101 is 373.5kgmol/hr. The flow rate of hot hydrogen recycle stream 104 is 35.3 kgmol/hr. This means that 338.2kgmol/hr of hydrogen is liquefied in the process. Liquid product flow rate is 15 metric tons/day, or 310.0 kgmol/hr. From the process to the time the truck leaves the factory gate, the estimated loss is 7-10%, or about 8.5%. Most of these losses can be recovered and recycled to the feed using appropriate equipment not described here.

The refrigeration required to produce this liquid product is provided by a low-pressure gas mixture 121 containing 51.4% hydrogen, 29.4% propane and 19.2% isopentane, which is compressed in the first gas mixture compressor 11 to 1.2 to 4.0 bar. This stream is mixed with the mixing vessel recycle feed 152 in the mixing vessel 13 and forms a second mixture 123 , compressed to 34.1 bar and separated in the second phase separator 19 . The second liquid 162 exiting the second phase separator 19 contains mostly isopentane and some propane and a small amount of dissolved hydrogen. This stream is cooled to 199.8 K in pre-cooling heat exchanger 1 and recycled to mixing vessel 13.

The second phase separator steam 127 leaves the top of the second phase separator 19 and is cooled to 155.3K in the pre-cooling heat exchanger 1 to form the first cooling mixed refrigerant 128, which is fed to the first mixed refrigeration agent separator 20. The first mixed refrigerant liquid 181 containing almost all remaining isopentane and most of the propane leaves the bottom of the first mixed refrigerant separator 20 and is split into streams 183A and 182, stream 183A being expanded to 4.1 bar and having 45.4 kgmol /hr molar flow, stream 182 is expanded to 1.3 bar and has a flow rate of 182.7 kgmol/hr. These two streams provide cooling in the pre-cooling heat exchanger and are recycled to the first (183B) and second (183A) stages of the mixed gas compressor.

The first mixed refrigerant vapor 129 containing 99.98% hydrogen leaves the top of the first mixed refrigerant separator 20 and returns to the pre-cooling heat exchanger 1, where it is further cooled to 110.9K to form a second cooled mixed refrigeration The refrigerant stream 130 is fed to the second mixed refrigerant separator 21 . The second mixed refrigerant liquid 184 contains most of the remaining propane and has a flow rate of only 0.3 kgmol/hr. It is discharged from the bottom of the second mixed refrigerant separator 21 and expands in the second mixed refrigerant liquid expansion device 48 (such as a valve). to cool and reduce the pressure of the return refrigerant stream 183B before it forms part of the return refrigerant stream 183B.

The second mixed refrigerant vapor 131 exits the top of the second mixed refrigerant separator 21 and is purified in the mixed refrigerant purifier 22 to remove any remaining propane, in this case less than 1 ppm. The purified hydrogen stream 132 leaves the mixed refrigerant purifier 22 and returns to the pre-cooling heat exchanger 1 where it is cooled to 80.1 K and leaves as cooling refrigerant 133 which in the second refrigerant purifier 23 is further purified, similar to mixed refrigerant purifier 22, except that the second refrigerant purifier removes 1 ppm of nitrogen from the original hydrogen feed. The low temperature refrigerant 134 exits the second refrigerant purifier 23 and is fed to the hydrogen liquefaction process.

After circulating in the closed loop through the liquefaction process, the pure hydrogen cryogenic refrigerant is returned as two separate streams: low pressure stream 141 and medium pressure stream 151. 1.3 bar of low pressure refrigerant 141 is recycled from the hydrogen liquefaction process and into the pre- Cooling heat exchanger 1 provides cooling and returns to the first stage of the mixed gas compressor. The medium pressure refrigerant 151 at 4.1 bar leaves the hydrogen liquefaction process and enters the pre-cooling heat exchanger 1 to provide cooling and returns to the second stage of the mixed gas compressor.

Table 1 - Flow conditions and composition used in Example 1. Table 1 stream name 101 102 103 104 121 123 Stream description Mutually steam steam steam steam steam steam temperature K 308.0 80.1 79.1 305.0 292.5 296.1 pressure -bar 20.0 19.9 1.4 1.4 1.2 4.0 flow kgmol/hr 373.5 373.5 35.3 35.3 372.4 2342.8 molecular weight kg/kgmol 2.0 2.0 2.0 2.0 27.8 10.8 Components H2 mole fraction 0.999999 0.999999 1.000000 1.000000 0.514377 0.847046 propane mole fraction 0.000000 0.000000 0.000000 0.000000 0.293648 0.067764 Isopentane mole fraction 0.000000 0.000000 0.000000 0.000000 0.191974 0.085188 N2 mole fraction 0.000000 0.000000 0.000000 0.000000 0.000001 0.000001 stream name 127 128 129 130 131 132 Stream description Mutually steam mix steam mix steam steam temperature K 308.1 155.3 155.3 110.9 110.9 110.9 pressure -bar 34.1 33.9 33.8 33.7 33.7 33.7 flow kgmol/hr 2207.5 2200.7 1973.0 1973.0 1972.7 1972.7 molecular weight kg/kgmol 7.5 7.5 2.0 2.0 2.0 2.0 Components H2 mole fraction 0.897428 0.897428 0.999827 0.999827 0.999999 0.999999 propane mole fraction 0.062009 0.062009 0.000171 0.000171 0.000000 0.000000 Isopentane mole fraction 0.040563 0.040563 0.000001 0.000001 0.000000 0.000000 N2 mole fraction 0.000001 0.000001 0.000001 0.000001 0.000001 0.000001 stream name 133 134 141 151 152 162 Stream description Mutually steam steam steam steam steam liquid temperature K 80.1 80.1 79.1 79.1 292.6 308.1 pressure -bar 33.4 33.3 1.3 4.1 4.0 34.1 flow kgmol/hr 1972.7 1972.7 189.7 1789.8 1970.4 135.3 molecular weight kg/kgmol 2.0 2.0 2.0 2.0 7.6 65.9 Components H2 mole fraction 0.999999 1.000000 1.000000 1.000000 0.910267 0.024986 propane mole fraction 0.000000 0.000000 0.000000 0.000000 0.024863 0.161671 Isopentane mole fraction 0.000000 0.000000 0.000000 0.000000 0.064869 0.813342 N2 mole fraction 0.000001 0.000000 0.000000 0.000000 0.000001 0.000001 stream name 166 181 183A 183B 184 Stream description Mutually liquid liquid mix liquid liquid temperature K 199.8 155.3 158.5 158.7 110.9 pressure -bar 34.1 33.8 4.1 1.3 33.7 flow kgmol/hr 135.3 227.7 45.4 182.7 0.3 molecular weight kg/kgmol 65.9 54.7 54.7 54.7 44.0 Components H2 mole fraction 0.0024987 0.010078 0.010079 0.010068 0.004398 propane mole fraction 0.161671 0.597864 0.597864 0.598597 0.992619 Isopentane mole fraction 0.813342 0.392058 0.392058 0.391335 0.002983 N2 mole fraction 0.000000 0.000001 0.000000 0.000000 0.000000

While the preferred embodiments of the present disclosure have been shown and described, it will be obvious to those skilled in the art that changes and modifications can be made therein without departing from the spirit of the disclosure, the scope of which is determined by The attached request is restricted.

1: Cooling heat exchanger 2, 3: ortho-secondary conversion catalyst 4: Replenish the refrigerant expander 5: Supplementary refrigerant compressor 6: Aftercooler 7: Cold box 11: First mixed gas compressor 12:First compressor aftercooler 13: Mixing container 14: Second mixed gas compressor 15:Second compressor aftercooler 16:Separation device 17: The third mixed gas compressor 18:Third compressor aftercooler 19:High-pressure accumulator 20: First mixed refrigerant separator 21: Second mixed refrigerant separator 22: Mixed refrigerant purifier 23: Second refrigerant purifier 24: Low pressure gas mixture container 31:External process 41: First phase separator valve 42: Second phase separation valve 43: Mixing container valve 44: Low pressure gas mixture container valve 45, 46: Refrigeration expansion device 47, 47A, 47B: expansion device 48:Liquid expansion device 49:Pump 51: Low temperature purifier 52: First cold heat exchanger catalyst channel 53:First heat and cold exchanger 54: Second cold heat exchanger catalyst channel 55: Second heat and cold exchanger 56: Third cold heat exchanger catalyst channel 57:Third heat and cold exchanger 58:Catalyst channel of the fourth cold and heat exchanger 59: The fourth heat and cold exchanger 60: Expansion valve 61:Separator 62: First hydrogen expander 63: Second hydrogen expander 64: Hydrogen refrigerant expansion valve 65:Refrigerant separator 101: High pressure hydrogen feed 102: Pre-cooled hydrogen feed 103: Cold hydrogen recirculation stream 104: Warm Hydrogen Recirculation Stream 111: High pressure supplementary refrigerant 112: Cold high pressure supplementary refrigerant flow 113: Cold supplemental refrigerant flow 114: Warm low pressure supplemental refrigerant flow 115: Thermal Compression Supplementary Refrigerant Flow 121:Low pressure gas mixture 122: First medium pressure mixture 123: Second mixture 124: Second medium pressure mixture 125:Third mixture 126:High pressure mixture 127: Second phase separator steam 128: First cooling mixed refrigerant 129: First mixed refrigerant vapor 130: Second cooling mixed refrigerant flow 131: Second mixed refrigerant vapor 132:Purified Helium Stream 133: Cooling refrigerant 134: Low temperature refrigerant 135: Pre-cooled hydrogen stream 136: Purifier product 141: Low pressure refrigerant 142: Warm mixed refrigerant 143: Low pressure gas mixture container feeding 151:Medium pressure refrigerant 152: Mixing vessel recirculation feed 160:First Liquid 161: Low pressure first liquid 162:Second liquid 163: Low pressure second liquid 164: Low pressure mixed liquid 165: Warm mixing vessel refrigeration feed 166, 167: Mixing container refrigeration feed 168: Refrigerants for cooling low-pressure gas mixture containers 169: Cooling mixed container refrigerant 170: Mixing vessel recirculation flow 171: Low pressure mixing vessel recirculation flow 172: Low pressure gas mixture container recirculation flow 173: Recirculation flow of reduced pressure gas mixture container 174: Cooling mixed container refrigerant 175: Accumulated liquid in mixing container 176: Pressurized accumulated liquid 181, 182: First mixed refrigerant liquid 183, 183A, 183B: Low-pressure mixed refrigerant recirculation flow 184, 185: Second mixed refrigerant liquid 191: Mixed refrigerant purifier regeneration feed 192: Regeneration stream containing impurities 193: Second refrigerant purifier regeneration feed 194: The second impurity-containing regeneration stream 191 mixed refrigerant purifier regeneration feed 192 Regeneration stream containing impurities 193 Second refrigerant purifier regeneration feed 194 Second impurity-containing regeneration logistics 201, 202, 203, 204, 205: Purified hydrogen feed 206: Two-phase hydrogen feed 207: Liquid hydrogen product 208:Cold hydrogen vapor 209, 210, 211: Warm hydrogen vapor flow 212: First supplementary refrigerant section 213, 220: first supplementary refrigerant 214: Second supplementary refrigerant part 215: Second supplementary refrigerant 216, 219: Supplementary refrigerant recirculation 217: Remaining supplementary refrigerant 218:Cold supplementary refrigerant 221:The first hydrogen refrigerant 222: First expander feed 223: Second cold heat exchanger refrigerant feed 224: First hydrogen expander product 225: First hydrogen expander product 226: Second hydrogen refrigerant 227: Second expander feed 228: Second hydrogen expander product 229: Cold refrigerant feed 231: Refrigerant feed to the third cold and heat exchanger 232:Third hydrogen refrigerant 233: Two-phase hydrogen refrigerant 234:Cold hydrogen refrigerant vapor 235: Second cold refrigerant feed 236: Third cold refrigerant feed 237:Liquid refrigerant 238: Second two-phase refrigerant 251: First supplementary refrigerant 252: Supplementary refrigerant return flow

Figure 1 is a process flow diagram illustrating a first embodiment of the pre-cooling portion of an embodiment of the system of the present disclosure.

Figure 2 is a process flow diagram illustrating an embodiment of the liquefaction portion of an embodiment of the disclosed system.

Figure 3 is a process flow diagram illustrating a second embodiment of the pre-cooling portion of an embodiment of the system of the present disclosure.

Figure 4 is a process flow diagram illustrating a third embodiment of the pre-cooling portion of an embodiment of the system of the present disclosure.

Figure 5 is a process flow diagram illustrating a fourth embodiment of the pre-cooling portion of an embodiment of the system of the present disclosure.

1: Cooling heat exchanger

2, 3: ortho-secondary conversion catalyst

4: Replenish the refrigerant expander

5: Supplementary refrigerant compressor

6: Aftercooler

7: Cold box

11: First mixed gas compressor

12:First compressor aftercooler

13: Mixing container

14: Second mixed gas compressor

15:Second compressor aftercooler

16:Separation device

17: The third mixed gas compressor

18:Third compressor aftercooler

19:High-pressure accumulator

20: First mixed refrigerant separator

21: Second mixed refrigerant separator

22: Mixed refrigerant purifier

23: Second refrigerant purifier

24: Low pressure gas mixture container

41: First phase separator valve

42: Second phase separation valve

43: Mixing container valve

44: Low pressure gas mixture container valve

45, 46: Refrigeration expansion device

48:Liquid expansion device

49:Pump

101: High pressure hydrogen feed

102: Pre-cooled hydrogen feed

103: Cold hydrogen recirculation stream

104: Warm Hydrogen Recirculation Stream

111: High pressure supplementary refrigerant

112: Cold high pressure supplementary refrigerant flow

113: Cold supplemental refrigerant flow

114: Warm low pressure supplemental refrigerant flow

115: Thermal Compression Supplementary Refrigerant Flow

121:Low pressure gas mixture

122: First medium pressure mixture

123: Second mixture

124: Second medium pressure mixture

125:Third mixture

126:High pressure mixture

127: Second phase separator steam

128: First cooling mixed refrigerant

129: First mixed refrigerant vapor

130: Second cooling mixed refrigerant flow

131: Second mixed refrigerant vapor

132:Purified Helium Stream

133: Cooling refrigerant

134: Low temperature refrigerant

141: Low pressure refrigerant

142: Warm mixed refrigerant

143: Low pressure gas mixture container feeding

151:Medium pressure refrigerant

152: Mixing vessel recirculation feed

161: Low pressure first liquid

162:Second liquid

163: Low pressure second liquid

164: Low pressure mixed liquid

166, 167: Mixing container refrigeration feed

168: Refrigerants for cooling low-pressure gas mixture containers

169: Cooling mixed container refrigerant

170: Mixing vessel recirculation flow

171: Low pressure mixing vessel recirculation flow

172: Low pressure gas mixture container recirculation flow

173: Recirculation flow of reduced pressure gas mixture container

174: Cooling mixed container refrigerant

175: Accumulated liquid in mixing container

176: Pressurized accumulated liquid

181, 182: First mixed refrigerant liquid

183: Low pressure mixed refrigerant recirculation flow

184, 185: Second mixed refrigerant liquid

191: Mixed refrigerant purifier regeneration feed

192: Regeneration stream containing impurities

193: Second refrigerant purifier regeneration feed

194: The second impurity-containing regeneration stream

Claims (53)

A system for cooling a feed stream containing hydrogen or helium with a mixed refrigerant consisting of: a. Pre-cooling heat exchanger, which has a feed flow cooling channel, a first refrigerant cooling channel, a second refrigerant cooling channel and a refrigerant heating channel; b. A compression system having an inlet in fluid communication with the refrigerant heating passage and configured to receive and increase the pressure of a refrigerant vapor stream including hydrogen and/or helium mixed with at least one other refrigerant gas, such that the molecular weight of the mixture is greater than 6kg/kgmol, and the compression system has an outlet in fluid communication with the first refrigerant cooling channel; c. A first refrigerant separation device configured to receive fluid from a first refrigerant cooling channel in the pre-cooling heat exchanger, the first refrigerant separation device having a liquid outlet in fluid communication with the refrigerant warming channel and steam outlets; d. A refrigerant purifier having a purifier inlet in fluid communication with the vapor outlet of the first refrigerant separation device and an outlet in fluid communication with a second refrigerant cooling channel, the second refrigerant cooling channel having a vapor outlet with the refrigerant The outlet of the heating channel fluid communication The system of claim 1, wherein the compression system includes: a first interstage compressor having an inlet and an outlet in fluid communication with the refrigerant warming passage; a first interstage aftercooler, having an inlet and an outlet configured to receive fluid from the first interstage compressor; a high pressure accumulator having an inlet in fluid communication with the first interstage aftercooler outlet, the high pressure accumulator having a vapor outlet and a liquid An outlet, the vapor outlet is in fluid communication with the first refrigerant cooling channel, and the liquid outlet is in fluid communication with a compression system. The system of claim 2, further comprising an interstage separation device having an inlet in fluid communication with the first interstage aftercooler outlet, a steam outlet in fluid communication with the high-pressure accumulator, and a steam outlet in fluid communication with the first interstage aftercooler outlet. The liquid outlet of the compression system is in fluid communication. The system according to claim 3, wherein the refrigerant warming channel includes a low-pressure refrigerant warming channel and a medium-pressure refrigerant warming channel, and wherein the compression system includes a mixed gas compressor having a configuration an inlet configured to receive fluid from the low-pressure refrigerant heating passage; a mixed gas aftercooler having an inlet configured to receive fluid from the mixed gas compressor; a mixing device having an inlet configured to receive fluid from the mixed gas aftercooler a first inlet of fluid, a second inlet configured to receive fluid from the medium-pressure refrigerant heating passage, a third inlet, a mixing device vapor outlet in fluid communication with the first interstage compressor, and a third inlet configured to receive fluid from the first interstage compressor. a second interstage compressor of fluid from the vapor outlet of the interstage separation device, a second interstage aftercooler configured to receive fluid from the second interstage compressor and direct the fluid to the high pressure accumulator, and further Includes a simultaneous heat and mass transfer control system that maintains control over the composition and thermal properties of the mixed refrigerant vapor leaving the vapor outlet of the mixing device, the simultaneous heat and mass transfer control system including at least one of the following: i) A mixing vessel valve having a valve inlet configured to receive fluid from the interstage separation device liquid outlet and the high pressure accumulator liquid outlet and a third inlet configured to direct fluid to the mixing device when the mixing vessel valve is opened. valve outlet; ii) Mixed gas aftercooler; and/or iii) First and/or second interstage aftercooler. The system according to claim 4, wherein the mixing device includes a liquid outlet in fluid communication with the low-pressure refrigerant warming channel and/or the medium-pressure refrigerant warming channel. The system according to claim 5, further comprising a pump having a pump inlet fluidly connected to the mixing device liquid outlet and fluidly connected to the low-pressure refrigerant warming channel and/or the medium-pressure refrigerant warming channel. The connected pump outlet is included in the simultaneous heat and mass transfer control system. The system of claim 4, wherein the mixing device includes a heating coil, and the heating coil is included in the simultaneous heat and mass transfer control system. The system according to claim 1, wherein the refrigerant purifier is selected from the group consisting of adsorbents, freezing devices and distillation towers. The system of claim 1, wherein a first refrigerant purifier regeneration stream is recycled to the compression system. The system of claim 9, wherein the second refrigerant purifier regeneration stream is removed from the liquefaction process by draining it or recycling it upstream of the feed stream cooling channel of the pre-cooling heat exchanger. The system of claim 1, wherein the pre-cooling heat exchanger has at least one supplemental refrigerant cooling channel and at least one supplemental refrigerant warming channel. The system of claim 11, wherein at least a portion of the supplemental refrigerant is used to provide refrigeration to an external process or system. The system of claim 1, wherein the feed stream and mixed refrigerant are purified in a combined purifier and the resulting purifier product is separated, with a portion of the purifier product directed to the feed The flow cooling channel, while the other part is directed to the compression system. The system of claim 1, further comprising an insulated cold box having an interior and an exterior, wherein the pre-cooling heat exchanger is located inside the cold box and the compression system is located outside the cold box . The system of claim 1, further comprising a primary refrigerant expansion device operating below ambient temperature, the primary refrigerant expansion device being configured to receive primary refrigerant from the liquid outlet of the first refrigerant separation device , reducing the temperature and pressure of the received main refrigerant, thereby providing expanded main refrigerant, and guiding the expanded main refrigerant to the refrigerant warming channel. A method of liquefying a feed stream containing hydrogen or helium, comprising the following steps: a. Mix hydrogen or helium refrigerant with at least one additional refrigerant component with a molecular weight higher than hydrogen or helium to form a mixed refrigerant with a molecular weight of at least 6kg/kgmol; b. Compress the mixed refrigerant using a compression system containing at least one dynamic compressor or dynamic compressor stage; c. Separate at least one additional refrigerant component from the hydrogen or helium refrigerant at a temperature of at least 75K to obtain the remaining hydrogen or helium refrigerant; d. Use the remaining hydrogen or helium refrigerant to cool the hydrogen or helium feed stream to produce a liquid hydrogen or helium product from the feed stream containing hydrogen or helium. The method of claim 16, wherein the at least one additional refrigerant component is selected from the group consisting of hydrocarbons containing at least three carbon atoms or neon, partially fluorinated hydrocarbons and perfluorinated hydrocarbons. The method of claim 16, wherein step c is accomplished using partial condensation and adsorption. The method of claim 16, wherein step c is accomplished using partial condensation and at least two adsorption steps operating at different temperatures, wherein the at least one additional component is removed at a first temperature, at a temperature higher than the first temperature. Impurities in the feed stream containing hydrogen or helium are removed at the lower second temperature, and the step of discharging the removed impurities is further included. The method of claim 16, further comprising the step of providing refrigeration in a heat exchanger to a feed stream containing hydrogen or helium using at least one additional refrigerant component separated in step c. The method of claim 20, further comprising the step of exporting refrigeration provided by the at least one additional refrigerant from the heat exchanger to a second process. The method of claim 21, wherein refrigeration provided by the at least one additional refrigerant is output from the heat exchanger using a flow of supplemental refrigerant below ambient temperature. The method of claim 20, wherein the step of providing refrigeration in a heat exchanger to a feed stream containing hydrogen or helium using at least one additional refrigerant component separated in step c includes removing from the heat exchanger Two-phase flow. The method of claim 16, wherein the step of cooling the hydrogen or helium feed stream is performed within a heat exchanger located within the cold box and the step of compressing the mixed refrigerant using a compression system is performed outside the cold box. A system for cooling a cryogenic fluid feed stream including hydrogen or helium with a mixed refrigerant, comprising: a. Pre-cooling heat exchanger, which has a pre-cooling feed flow cooling channel, a low-pressure refrigerant heating channel, a medium-pressure refrigerant heating channel, a first refrigerant cooling channel and a second refrigerant cooling channel; b. A mixed gas compressor configured to receive a flow of mixed refrigerant vapor from the low pressure refrigerant heating passage; c. Mixed gas aftercooler in fluid communication with the mixed gas compressor; d. A mixing device having a first inlet in fluid communication with the mixed gas aftercooler, a second inlet and a mixing device vapor outlet, the second inlet being configured to receive mixed refrigerant vapor from the medium-pressure refrigerant warming channel flow; e. A first interstage compressor in fluid communication with the vapor outlet of the mixing device; f. A first interstage aftercooler in fluid communication with the first interstage compressor; g. A high-pressure accumulator in fluid communication with the first interstage aftercooler and having a high-pressure accumulator steam outlet and a high-pressure accumulator liquid outlet, the high-pressure accumulator steam outlet being connected to the first refrigerant cooling channel Fluid communication, the high-pressure accumulator liquid outlet is in fluid communication with the medium-pressure refrigerant heating channel; h. The first refrigerant separation device is in fluid communication with the first refrigerant cooling channel and has a first refrigerant separation device liquid outlet in fluid communication with the low-pressure refrigerant heating channel and in fluid communication with the second refrigerant cooling channel. The steam outlet of the first refrigerant separation device; i. A second refrigerant separation device that is in fluid communication with the second refrigerant cooling channel and has a second refrigerant separation device liquid outlet and a second refrigerant separation device vapor outlet that are in fluid communication with the low-pressure refrigerant heating channel; j. A refrigerant purifier having a purifier inlet and a purifier outlet in fluid communication with the steam outlet of the second refrigerant separation device, wherein the purifier outlet is in fluid communication with the low-pressure refrigerant heating channel and the medium-pressure refrigerant heating channel. . The system of claim 25, further comprising: k. A liquefaction heat exchanger having a liquefaction feed flow cooling channel configured to receive a pre-cooled feed flow cooling channel from the pre-cooling feed flow cooling channel, a low-pressure refrigerant addition configured to direct refrigerant to the pre-cooling heat exchanger. a liquefied low-pressure refrigerant warming passage of the warm passage, a liquefied intermediate-pressure refrigerant warming passage configured to direct refrigerant to the pre-cooling heat exchanger, a third liquefied intermediate-pressure refrigerant warming passage in fluid communication with the purifier outlet. a refrigerant cooling channel and a fourth refrigerant cooling channel configured to receive the first refrigerant portion from the third refrigerant cooling channel; l. A first expansion device configured to receive the second refrigerant portion from the third refrigerant cooling passage and to direct the expanded second refrigerant portion to the liquefied intermediate-pressure refrigerant warming passage; m. A second expansion device configured to receive the cooled first refrigerant portion from the fourth refrigerant cooling passage and to direct the expanded cooled first refrigerant portion to the liquefied low pressure refrigerant warming passage. The system of claim 26, wherein the liquefaction heat exchanger includes a first liquefaction heat exchanger including the third refrigerant cooling channel and a second liquefaction heat exchanger including the fourth refrigerant cooling channel. device, and wherein the liquefied feed flow cooling channel, the liquefied low-pressure refrigerant warming channel and the liquefied intermediate-pressure refrigerant warming channel pass through the first and second liquefaction heat exchangers. The system according to claim 26, further comprising a recirculation channel passing through the liquefaction heat exchanger and the precooling heat exchanger, and further comprising a product expansion device and a product separation device, the product expansion device being configured to extract from the The liquefied feed stream cooling passage receives the liquid product stream and directs the resulting expanded product fluid stream to a product separation device having a product separation device vapor outlet and a product separation device liquid outlet in fluid communication with the recirculation passage. The system of claim 25, further comprising a refrigerant expansion device having an inlet in fluid communication with the liquid outlet of the high pressure accumulator and an outlet in fluid communication with the medium pressure refrigerant warming passage. The system of claim 25, wherein the mixing device includes a sprayer and/or a heating coil. The system according to claim 25, wherein the pre-cooling heat exchanger further includes a first supplementary refrigerant warming channel, a second supplementary refrigerant warming channel and a supplementary refrigerant cooling channel, and further includes: k. A first supplemental refrigerant compressor configured to receive a first supplemental refrigerant vapor flow from the first supplemental refrigerant warming passage; l. A first supplemental aftercooler in fluid communication with the first supplemental refrigerant compressor; m. A second supplemental refrigerant compressor in fluid communication with the first supplemental aftercooler and configured to receive a second supplemental refrigerant vapor flow from the second supplemental refrigerant warming passage; n. a second supplemental aftercooler in fluid communication with the second supplemental refrigerant compressor, the second supplemental aftercooler having a second supplemental aftercooler outlet configured to direct fluid to the supplemental refrigerant cooling passage; o. A third expansion device having a third expansion device inlet in fluid communication with the supplemental refrigerant cooling passage and a third expansion device outlet in fluid communication with the second supplemental refrigerant warming passage; p. A fourth expansion device having a fourth expansion device inlet in fluid communication with the supplemental refrigerant cooling passage and a fourth expansion device outlet in fluid communication with the first supplemental refrigerant warming passage. The system of claim 25, wherein the mixed gas compressor and the first interstage compressor are dynamic compressors or staged dynamic compressors. The system of claim 25, wherein the mixing device includes a mixing device liquid outlet, and further includes: k. An interstage separation device in fluid communication with the first interstage compressor and having a vapor outlet of the interstage separation device and a liquid outlet of the interstage separation device; l. A second interstage compressor in fluid communication with the steam outlet of the interstage separation device; m. A second interstage aftercooler having an inlet in fluid communication with the second interstage compressor and an outlet in fluid communication with the high-pressure accumulator; n. The mixing device liquid outlet, the interstage separation device liquid outlet and the high-pressure accumulator liquid outlet are configured to combine the liquid leaving the mixing device, the interstage separation device and the high-pressure accumulator, so that a combined refrigeration is formed The refrigerant liquid flow is guided to the low-pressure refrigerant heating channel and the medium-pressure refrigerant heating channel. The system of claim 33, wherein the pre-cooling heat exchanger includes a combined refrigerant liquid flow cooling passage, and wherein the combined refrigerant liquid flow is directed to the low pressure refrigerant warming passage It is cooled in the combined refrigerant liquid flow cooling channel. The system of claim 33, wherein the mixed gas compressor, the first interstage compressor and the second interstage compressor are dynamic compressors or staged dynamic compressors. The system of claim 25, wherein the first refrigerant separation device liquid outlet is also in fluid communication with the medium-pressure refrigerant warming channel. The system of claim 36, further comprising: a fifth expansion device configured to receive fluid from the first refrigerant separation device liquid outlet and direct the expanded fluid to the intermediate pressure refrigerant warming passage ; and a sixth expansion device configured to receive fluid from the liquid outlet of the first refrigerant separation device and guide the expanded fluid to the low-pressure refrigerant warming channel. The system of claim 25, further comprising a refrigerant purifier line in fluid communication with the refrigerant purifier and the mixed gas compressor, and configured such that a refrigerant purifier regeneration flow flows from the refrigerant purifier Recirculated to the compression system. The system according to claim 25, wherein the pre-cooling heat exchanger further includes a supplementary refrigerant heating channel and a supplementary refrigerant cooling channel, and further includes: k. A supplemental refrigerant compressor configured to receive the first supplemental refrigerant vapor flow from the supplemental refrigerant heating passage; l. A supplemental aftercooler having an inlet in fluid communication with the supplemental refrigerant compressor and an outlet in fluid communication with the supplemental refrigerant cooling channel; m. A third expansion device having an inlet in fluid communication with the supplemental refrigerant cooling passage and a third expansion device outlet in fluid communication with the supplemental refrigerant warming passage. The system of claim 39, wherein the mixed gas compressor, first interstage compressor and supplemental refrigerant compressor are dynamic compressors or staged single dynamic compressors. The system of claim 25, wherein the refrigerant purifier is selected from the group consisting of adsorbents, freezing devices and distillation towers. The system of claim 25, wherein the refrigerant purifier is a freezing device. The system of claim 42, further comprising a refrigerant purifier line in fluid communication with the freezing device and the mixed gas compressor and configured to recirculate a refrigerant purifier regeneration flow from the freezing device to The compression system. The system of claim 42, wherein the refrigerant purifier is a purifier heat exchanger. The system of claim 44, wherein the purifier heat exchanger is a brazed aluminum heat exchanger or a tubular heat exchanger. The system of claim 44, wherein the purifier heat exchanger includes a filter configured to capture frozen high molecular weight species. The system of claim 25, wherein the refrigerant purifier is a first refrigerant purifier having a first refrigerant purifier outlet, and further comprising a first refrigerant purifier having a first refrigerant purifier outlet in fluid communication with the first refrigerant purifier outlet. A second refrigerant purifier at the inlet of the two refrigerant purifiers, wherein the first refrigerant purifier is configured to remove higher molecular weight impurities with boiling points above 80 K, and the second refrigerant purifier is configured to remove lighter molecular weight impurities. The system of claim 47, wherein the higher molecular weight impurities include hydrocarbons and the lighter molecular weight impurities include nitrogen and/or argon. The system of claim 48, further comprising a refrigerant purifier line in fluid communication with the first refrigerant purifier and the mixed gas compressor and configured such that the refrigerant purifier includes higher molecular weight impurities A regeneration stream is recycled from the freezing device to the compression system. The system of claim 49, wherein the second refrigerant purifier is configured to exhaust the lighter molecular weight impurities to the atmosphere. The system of claim 47, further comprising a purified refrigerant cooling channel in the pre-cooling heat exchanger configured to receive fluid from the first refrigerant purifier outlet and direct the cooling fluid to The second refrigerant purifier inlet. The system of claim 25, wherein the refrigerant purifier is configured to remove nitrogen and/or argon impurities and hydrocarbon impurities from the refrigerant stream. The system of claim 52, further comprising a refrigerant purifier line in fluid communication with the refrigerant purifier and the mixed gas compressor and configured to include nitrogen and/or argon impurities as well as hydrocarbon impurities. The refrigerant purifier regeneration stream is recirculated from the freezing device to the compression system.