The present invention provides a method of liquefying a contaminated hydrocarbon-containing gas stream: (a) providing a CO2 contaminated hydrocarbon-containing gas stream (20); (b) cooling the contaminated hydrocarbon-containing gas stream to obtain a partially liquefied stream (70); (c) separating the partially liquefied stream obtaining a liquid stream (90); (d) cooling the liquid stream (90) in a direct contact heat exchanger (200) obtaining a multiphase stream (201) containing at least a liquid phase and a solid CO2 phase; (e) separating the multiphase stream in a solid-liquid separator (202) obtaining a CO2 depleted liquid stream (141); (f) passing the CO2 depleted liquid stream (141) to a further cooling, pressure reduction and separation stage to generate a further CO2 enriched slurry stream (206); (g) passing at least part of the further CO2 enriched slurry stream (206) to the direct contact heat exchanger (200) to provide cooling duty to and mix with the liquid stream (90).

Process for liquefying natural gas in a cryogenic heat exchanger by flowing in indirect contact with refrigerant fluid entering heat exchanger at a first inlet at temperature T0 and pressure P1, and flowing through the exchanger as co-current with the natural gas stream, leaving the heat exchanger in the liquid state, then being expanded at the cold end of the exchanger to return to gaseous state at a pressure P1 P1 and temperature T1 T0, before leaving the hot end of exchanger by outlet orifice in gaseous state T0. The fluid is then reliquefied to the inlet of the exchanger via compression followed by partial condensation and phase separation, a first liquid phase taken to the first inlet, a first gaseous portion compressed by a second compressor and cooled in desuperheater by contact with portion of the first liquid phase, prior to condensing in a second condenser.

A process for removing a foulant from a gas stream is disclosed. The gas stream is cooled in a series of heat exchangers, causing a portion of the foulant to desublimate and become entrained in a cryogenic liquid. This foulant slurry stream is pressurized, cooled, and separated into a pressurized foulant solid stream and the cryogenic liquid stream. The pressurized foulant solid stream is melted to produce a liquid foulant stream. Heat exchange processes, both internal and external, are provided that close the heat balance of the process. In this manner, the foulant is removed from the gas stream.

A hydrocyclone for separating a vapor from a carrier gas is disclosed. The hydrocyclone comprises one or more nozzles. A cryogenic liquid is injected to a tangential feed inlet at a velocity that induces a tangential flow and a cyclone vortex in the hydrocyclone. The carrier gas is injected into the cryogenic liquid, causing the vapor to dissolve, condense, desublimate, or a combination thereof, forming a vapor-depleted carrier gas and a vapor-enriched cryogenic liquid. The vapor-depleted carrier gas is drawn through a vortex finder and the vapor-enriched cryogenic liquid is drawn through an apex nozzle outlet. In this manner, the vapor is removed from the carrier gas.

An air-sparged hydrocyclone for separating a vapor from a carrier gas is disclosed. The cyclone comprises a porous sparger covered by an outer gas plenum. A cryogenic liquid is injected to a tangential feed inlet at a velocity that induces a tangential flow and a cyclone vortex in the air-sparged hydrocyclone. The carrier gas is injected into the cyclone through the porous sparger. The vapor dissolves, condenses, desublimates, or a combination thereof, forming a vapor-depleted carrier gas and a vapor-enriched cryogenic liquid. The vapor-depleted carrier gas is drawn through a vortex finder and the vapor-enriched cryogenic liquid is drawn through an apex nozzle outlet. In this manner, the vapor is removed from the carrier gas.

A method for separating a vapor from a carrier gas is disclosed. A hydrocyclone is provided with one or more nozzles on the wall of the hydrocyclone. A cryogenic liquid is provided to the tangential feed inlet at a velocity that induces a tangential flow and a cyclone vortex in the hydrocyclone. The carrier gas is injected into the hydrocyclone through the one or more nozzles. The vapor dissolves, condenses, desublimates, or a combination thereof, forming a vapor-depleted carrier gas and a vapor-enriched cryogenic liquid. The vapor-depleted gas is drawn through the vortex finder while the vapor-enriched cryogenic liquid is drawn through the apex nozzle outlet. In this manner, the vapor is removed from the carrier gas.

Embodiments described herein provide methods and systems for separating a mixed ethane and CO.sub.2. A method described includes generating a liquid stream including ethane and CO.sub.2. The liquid stream is flashed to form an ethane vapor stream and solid CO.sub.2. The solid CO.sub.2 is accumulated in an accumulation vessel and the gas is removed from the top of the accumulation vessel.

A method for cryogenic cooling without fouling is disclosed. The method comprises providing a first cryogenic liquid saturated with a dissolved gas; expanding the first cryogenic liquid into a separation vessel, separating into a vapor, a second cryogenic liquid, and a first solid; drawing the vapor into a heat exchanger and the second cryogenic liquid and the first solid out of the separation vessel; cooling the vapor against a coolant through the heat exchanger, causing the vapor to form a third cryogenic liquid and a second solid, the second solid dissolving in the third cryogenic liquid; and combining the second cryogenic liquid and the first solid with the third cryogenic liquid, producing a final cooled slurry. In this manner, the cryogenic cooling is accomplished without fouling.

The invention relates to a of processing a liquid natural gas stream at a LNG import terminal. The method comprises operating a vaporization unit obtaining a pressurized vaporized natural gas stream and operating a slushification unit to obtain a slush of liquid and solids and a cooled vapour phase. The method further comprises withdrawing the cooled vapour phase from the slushifier providing a cooled vapour stream and passing the cooled vapour stream to the vaporization unit.

Olefins may be recovered from a methanol to olefins reactor effluent by initially feeding the effluent to an absorber demethanizer to contact the effluent with an absorbent to recover an overheads including methane and ethylene and a bottoms including the absorbent, ethylene, and ethane. The bottoms are separated to recover an ethylene fraction and an ethane fraction. The overheads are cooled and partially condensed in a first heat exchanger to a temperature of 40 C. or greater. The resulting stream, or a portion thereof, may be further cooled and condensed via indirect heat exchange with a mixed refrigerant to a temperature of less than 40 C. The non-condensed vapors are separated from the condensed liquids to form a liquid fraction and a methane fraction. The liquid fraction is fed to the absorber demethanizer as reflux, and the methane and ethane fractions combined to form the mixed refrigerant.