Hydrogen Liquefaction System and Method

Abstract

A system and method for liquefying a hydrogen gas feed stream uses a pre-cooling refrigerant for pre-cooling the feed stream, where the pre-cooling refrigerant is compressed, cooled and then separated to provide high pressure mixed refrigerant vapor and liquid streams. The high pressure vapor stream is cooled and directed to a cold vapor separator where cold separator liquid and vapor streams are formed. The cold separator vapor stream is cooled and expanded to provide a pre-cool refrigeration stream in a heat exchanger system. The high pressure pre-cooling refrigerant liquid and cold separator liquid streams are cooled and expanded and directed to the pre-cool refrigeration stream. A high pressure primary refrigerant steam, after compression and cooling, is further cooled in the heat exchanger system and then expanded using warm and cold expanders, with the resulting expanded primary refrigerant streams used to liquefy the pre-cooled hydrogen feed stream via heat exchange in the heat exchanger system.

What is claimed is: 
     
         1 . A system for liquefying hydrogen gas feed comprising:
 a. a heat exchanger system having a feed gas inlet configured to receive the hydrogen gas feed stream, a product outlet, a cooling passage in fluid communication with the feed gas inlet and the product outlet, a primary refrigerant feed passage, a primary refrigeration passage and a pre-cooling refrigeration passage;   b. a primary refrigerant compression system configured to direct a conditioned primary refrigerant to the primary refrigerant feed passage;   c. a warm expander in fluid communication with the primary refrigerant feed passage, said warm expander having a warm expander outlet in fluid communication with the heat exchanger system and the primary refrigerant compression system;   d. a cold expander in fluid communication with the primary refrigerant feed passage, said cold expander having a cold expander outlet in fluid communication with the primary refrigeration passage;   e. an intermediate cooling passage within the heat exchanger system in fluid communication with the warm expander and the cold expander;   f. said cooling passage configured so that hydrogen therein is cooled and liquefied by countercurrent heat exchange with primary refrigerant in the primary refrigeration passage;   g. said primary refrigerant compression system configured to receive, compress and cool vaporized primary refrigerant from the primary refrigeration passage so that a conditioned primary refrigerant is provided;   h. a pre-cooling refrigerant compression system configured to receive, compress and cool a pre-cooling refrigerant vapor from an outlet of the pre-cooling refrigerant passage so that a conditioned pre-cooling refrigerant is provided to an inlet of the pre-cooling refrigerant passage;   i. said cooling passage configured so that hydrogen therein is cooled by countercurrent heat exchange with pre-cooling refrigerant in the pre-cooling refrigeration passage.   
     
     
         2 . The system of  claim 1  wherein the warm expander is configured to receive a first portion of primary refrigerant from the primary refrigerant feed passage and the warm expander and the cold expander are turbines that power either compressors or generators and further comprising:
 j. said intermediate cooling passage within the heat exchanger system configured to receive and cool fluid from the warm expander and to direct fluid to the cold expander, wherein said cold expander outlet is configured to direct an expanded first portion of primary refrigerant to the primary refrigeration passage; 
 k. a primary feed expansion device configured to receive and expand a second portion of primary refrigerant that has been further cooled in the primary refrigerant feed passage and direct an expanded second portion of the primary refrigerant to the heat exchanger system. 
 
     
     
         3 . The system of  claim 2  further comprising:
 l. a supplemental cold expansion device configured to direct fluid to the primary refrigeration passage; 
 m. a supplemental intermediate cooling passage within the heat exchanger system configured to receive and cool fluid from the cold expander and to direct fluid to the supplemental cold expansion device. 
 
     
     
         4 . The system of  claim 1  wherein the warm expander is a first warm expander configured to receive a first portion of primary refrigerant from the primary refrigerant feed passage and further comprising:
 j. a second warm expander configured to receive a first portion of fluid from the first warm expander and to direct fluid to the primary refrigeration passage; 
 k. said intermediate cooling passage within the heat exchanger system configured to receive and cool a second portion of fluid from the first warm expander and to direct fluid to the cold expander; 
 l. a primary feed expansion device configured to receive and expand a second portion of primary refrigerant that has been further cooled in the primary refrigerant feed passage and direct an expanded second portion of the primary refrigerant to the heat exchanger system. 
 
     
     
         5 . The system of  claim 1  wherein the heat exchanger system includes a first primary refrigeration passage and the primary refrigeration passage is a second primary refrigeration passage and the warm expander is configured to receive a first portion of primary refrigerant from the primary refrigerant feed passage and further comprising:
 j. an intermediate expander configured to receive a second portion of primary refrigerant from the primary refrigerant feed passage and to direct an expanded second portion of primary refrigerant to the first primary refrigeration passage; 
 k. said intermediate cooling passage within the heat exchanger system configured to receive and cool fluid from the warm expander and to direct fluid to the cold expander, wherein said cold expander outlet is configured to direct an expanded first portion of primary refrigerant to the second primary refrigeration passage; 
 l. a primary feed expansion device configured to receive and expand a third portion of primary refrigerant that has been further cooled in the primary refrigerant feed passage and direct an expanded third portion of the primary refrigerant to the heat exchanger system. 
 
     
     
         6 . A system for liquefying hydrogen gas feed comprising:
 a. a heat exchanger system having a feed gas inlet configured to receive the hydrogen gas feed stream, a product outlet, a cooling passage in fluid communication with the feed gas inlet and the product outlet, a primary refrigerant feed passage, a first primary refrigeration passage, a second primary refrigeration passage and a pre-cooling refrigeration passage;   b. a primary refrigerant compression system configured to direct a conditioned primary refrigerant to the primary refrigerant feed passage;   c. a first warm expander configured to receive a first portion of primary refrigerant from the primary refrigerant feed passage;   d. a second warm expander configured to direct fluid to the first primary refrigeration passage;   e. an intermediate cooling passage within the heat exchanger system configured to receive and cool fluid from the first warm expander and to direct fluid to the second warm expander;   f. a cold expander configured to receive a second portion of primary refrigerant from the primary refrigerant feed passage and direct an expanded second portion of primary refrigerant to the second primary refrigeration passage;   g. said cooling passage configured so that hydrogen therein is cooled and liquefied by countercurrent heat exchange with primary refrigerant in the first and second primary refrigeration passages;   h. said primary refrigerant compression system configured to receive, compress and cool vaporized primary refrigerant from the first and second primary refrigeration passages so that a conditioned primary refrigerant is provided;   i. a pre-cooling refrigerant compression system configured to receive, compress and cool a pre-cooling refrigerant vapor from an outlet of the pre-cooling refrigerant passage so that a conditioned pre-cooling refrigerant is provided to an inlet of the pre-cooling refrigerant passage;   j. said cooling passage configured so that hydrogen therein is cooled by countercurrent heat exchange with pre-cooling refrigerant in the pre-cooling refrigeration passage; and   k. a primary feed expansion device configured to receive and expand a third portion of primary refrigerant that has been further cooled in the primary refrigerant feed passage and direct an expanded third portion of the primary refrigerant to the heat exchanger system.