Cryogenic gas cooling system and method

A method for precooling a second cryogenic fluid using a first cryogenic fluid comprising the steps of:

• a. dividing a first cryogenic fluid stream into a motive stream and a secondary cooling stream;
• b. directing the motive stream to an ejector having a suction port;
• c. expanding the secondary cooling stream;
• d. cooling a second cryogenic fluid using at least a portion of the expanded secondary cooling stream so that a warmed first cryogenic fluid is formed;
• e. directing the warmed first cryogenic into the suction port of the ejector;
• f. separating a first cryogenic fluid mixed phase stream from an outlet of the ejector into a vapor stream and a liquid recycle stream;
• g. pumping at least a portion of the liquid recycle stream for use as the first cryogenic fluid stream in step a.

A system for liquefying a cryogenic gas feed stream comprising:

• a. a first precool heat exchanger;
• b. a second precool heat exchanger;
• c. a liquefier heat exchanger;
• d. a natural gas precool refrigeration circuit including:
• i) a liquid natural gas warming passage of the first precool heat exchanger configured to receive and warm a liquid natural gas feed stream;
• ii) a first precool expansion device configured to receive a fluid stream from the liquid natural gas warming passage of the first precool heat exchanger;
• iii) a first precool separation device having first precool separation device vapor outlet configured to direct fluid to an inlet of a natural gas warming passage of the first precool heat exchanger, said first precool separation device also having a first precool separation device liquid outlet and configured to receive and separate a fluid stream from the first precool expansion device so that a natural gas vapor stream exits the first precool separation device vapor outlet and a liquid natural gas stream exits the first precool separation device liquid outlet;
• iv) a second precool expansion device configured to receive a liquid natural gas stream from the first precool separation device liquid outlet and direct an expanded fluid stream to an inlet of an expanded fluid warming passage of the first precool heat exchanger;
• v) a first precool compressor having an inlet in fluid communication with an outlet of the expanded fluid warming passage of the first precool heat exchanger so as to lower the pressure within the expanded fluid warming passage;
• e. a nitrogen precool refrigeration circuit comprising:
• i) a nitrogen cooling passage of the first heat exchanger;
• ii) a third precool expansion device configured to receive and expand a fluid stream from the nitrogen cooling passage of the first heat exchanger;
• iii) a second precool separation device having an inlet configured to receive an expanded fluid from the third precool separation device, a second precool separation device vapor outlet and a second precool separation device liquid outlet, said second precool separation device configured to receive and separate a fluid stream from the third precool expansion device so that a nitrogen vapor stream exits the second precool separation device vapor outlet and a liquid nitrogen stream exits the second precool separation device liquid outlet;
• iv) said second precool heat exchanger having a liquid nitrogen warming passage configured to receive and warm a liquid nitrogen stream from the second precool separation device liquid outlet;
• v) said first precool heat exchanger having a nitrogen vapor warming passage having an inlet in fluid communication with outlets of the liquid nitrogen warming passage of the second precool heat exchanger and the second precool separation device vapor outlet;
• vi) a nitrogen compression and cooling system having an inlet in fluid communication with an outlet of the nitrogen vapor warming passage and an outlet in fluid communication with the nitrogen cooling passage of the first heat exchanger;
• f. a primary refrigeration circuit including:
• i) a first primary refrigerant precooling passage in the first precool heat exchanger and a second primary refrigerant precooling passage in the second precool heat exchanger each configured to receive and precool a stream of primary refrigerant;
• ii) a primary refrigerant adsorber configured to receive a precooled primary refrigerant stream from the second primary refrigerant precooling passage of the second precool heat exchanger;
• iii) a liquefier primary refrigerant cooling passage of the liquefier heat exchanger configured to receive a primary refrigerant stream from the primary refrigerant adsorber;
• iv) a first primary refrigerant expander having an inlet in fluid communication with the primary refrigerant cooling passage and configured to receive a first portion of a primary refrigerant flowing through the primary refrigerant cooling passage, said first primary refrigerant expander having an outlet configured to direct expanded primary refrigerant to a first liquefier primary refrigerant warming passage of the liquefier heat exchanger;
• v) a first primary refrigerant expansion device having an inlet configured to receive a second portion of primary refrigerant from the first liquefier primary refrigerant cooling passage and an outlet in fluid communication with a second liquefier primary refrigerant warming passage of the liquefier heat exchanger;
• vi) a first precool primary refrigerant warming passage of the first precool heat exchanger configured to receive and warm a primary refrigerant stream from the first liquefier primary refrigerant warming passage and a second precool primary refrigerant warming passage of the first precool heat exchanger configured to receive and warm a secondary refrigerant stream from the second liquefier primary refrigerant warming passage;
• vii) a primary refrigerant compression and cooling system having a first inlet in fluid communication with an outlet of the first precool primary refrigerant warming passage and a second inlet in fluid communication with an outlet of the second precool primary refrigerant warming passage and an outlet configured to direct primary refrigerant to the inlet of the first primary refrigerant precooling passage in the first precool heat exchanger;
• g. said first precool heat exchanger including a first cryogenic fluid precooling passage configured to receive and cool a cryogenic feed gas stream and said second precool heat exchanger including a second cryogenic fluid precooling passage configured to receive and cool a cryogenic feed gas stream from the first cryogenic fluid precooling passage;
• h. a precool adsorber having an inlet configured to received precooled cryogenic fluid from the second cryogenic fluid precooling passage from the second precool heat exchanger;
• i. a first cryogenic fluid cooling passage of the first liquefier heat exchanger in fluid communication with the precool adsorber and configured to cool cryogenic fluid therein;
• j. a first liquefier adsorber configured to receive cryogenic fluid from the first cryogenic fluid cooling passage;
• k. a second cryogenic fluid cooling passage of the first liquefier heat exchanger configured to receive and cool cryogenic fluid from the first liquefier adsorber;
• l. a second liquefier adsorber in fluid communication with the second cryogenic fluid cooling passage.