Apparatus for precooling hydrogen for liquefaction using external liquid nitrogen and high pressure gaseous nitrogen

An integrated industrial unit comprising:

• a nitrogen source configured to provide liquid nitrogen and pressurized gaseous nitrogen;
• a hydrogen source configured to provide gaseous hydrogen at a pressure of at least 15 bar(a);
• a hydrogen liquefaction unit, wherein the hydrogen liquefaction unit comprises a precooling system, and a liquefaction system;
• and
• a liquid hydrogen storage tank,
• wherein the precooling system is configured to receive the gaseous hydrogen from the hydrogen source and cool the gaseous hydrogen to a temperature between 70K and 100K,
• wherein the precooling system comprises a primary refrigeration system and a secondary refrigeration system,
• wherein the liquefaction system is in fluid communication with the precooling system and is configured to liquefy the gaseous hydrogen received from the precooling system to produce liquid hydrogen,
• wherein the liquid hydrogen storage tank is in fluid communication with the liquefaction system and is configured to store the liquid hydrogen received from the liquefaction system,
• wherein the primary refrigeration system comprises expanders configured to expand the pressurized gaseous nitrogen, wherein the expanders are configured to have an outlet pressure of P1,
• wherein the secondary refrigeration system provides refrigeration to the precooling system by vaporization of the liquid nitrogen at pressure P2, wherein the primary and secondary refrigerants are in fluid communication,
• wherein the nitrogen source comprises an air separation unit,
• wherein the hydrogen source is a hydrogen generation unit,
• wherein the air separation unit is configured to produce at least an oxygen stream, the pressurized gaseous nitrogen, and the liquid nitrogen, wherein the air separation unit is in fluid communication with the hydrogen generation unit and the precooling system, such that the air separation unit is configured to send the oxygen stream to the hydrogen generation unit, the pressurized nitrogen gaseous stream to the primary refrigeration system, and the liquid nitrogen to the secondary refrigeration system,
• wherein the pressurized gaseous nitrogen is provided as a first nitrogen product stream from the air separation unit and the liquid nitrogen is provided as a separate, second nitrogen product stream from the air separation unit, wherein the first and second nitrogen product streams are supplied as utilities to the hydrogen liquefaction unit.

An integrated industrial unit comprising:

• a nitrogen source configured to provide liquid nitrogen and pressurized gaseous nitrogen;
• a hydrogen source configured to provide gaseous hydrogen at a pressure of at least 15 bar(a), wherein the hydrogen source is a hydrogen generation unit;
• a hydrogen liquefaction unit, wherein the hydrogen liquefaction unit comprises a precooling system, and a liquefaction system;
• and
• a liquid hydrogen storage tank,
• wherein the precooling system is configured to receive the gaseous hydrogen from the hydrogen source and cool the gaseous hydrogen to a temperature between 70K and 100K,
• wherein the precooling system comprises a primary refrigeration system and a secondary refrigeration system,
• wherein the liquefaction system is in fluid communication with the precooling system and is configured to liquefy the gaseous hydrogen received from the precooling system to produce liquid hydrogen,
• wherein the liquid hydrogen storage tank is in fluid communication with the liquefaction system and is configured to store the liquid hydrogen received from the liquefaction system,
• wherein the primary refrigeration system provides refrigeration by expansion of the pressurized gaseous nitrogen,
• wherein the secondary refrigeration system provides refrigeration by vaporization of the liquid nitrogen,
• wherein the nitrogen source is an air separation unit, wherein the air separation unit is configured to produce at least an oxygen stream, the pressurized gaseous nitrogen, and the liquid nitrogen, wherein the air separation unit is in fluid communication with the hydrogen generation unit and the precooling system, such that the air separation unit is configured to send the oxygen stream to the hydrogen generation unit, the pressurized nitrogen gaseous stream to the primary refrigeration system, and the liquid nitrogen to the secondary refrigeration system
• wherein the integrated industrial unit further comprises a control system configured to control a flow rate of the liquid nitrogen to the secondary refrigeration system as a function of a flow rate of the oxygen stream sent to the hydrogen generation unit, thereby optimizing the energy balance of the integrated industrial unit.