Disclosed is a BOG reliquefaction system. The BOG reliquefaction system includes: a compressor compressing BOG; a heat exchanger cooling the BOG compressed by the compressor through heat exchange using BOG discharged from a storage tank as a refrigerant; a bypass line through which the BOG is supplied to the compressor after bypassing the heat exchanger; a second valve disposed on a second supply line through which the BOG used as the refrigerant in the heat exchanger is supplied to the compressor, the second valve regulating a flow rate of fluid and opening/closing of the second supply line; and a pressure reducer disposed downstream of the heat exchanger and reducing a pressure of fluid cooled by the heat exchanger, wherein the compressor includes at least one oil-lubrication type cylinder and the bypass line is joined to the second supply line downstream of the second valve.

A system and method for capturing and separating carbon dioxide from mixed gas streams. The gas stream is processed in a structure including a compression module comprising a plurality of compressors, intercoolers and inter-stage condensate separators. The flow path from the compression module includes a plurality of flow separators, gas stream splitters, heat exchangers and at least a first mixer and a first expander. The gas stream is sequentially compressed and cooled to form process condensate and separate it from the compressed gas stream. The gas stream is further dried and cooled to liquefy carbon dioxide and separate it from the non-condensable portion. Selective expansion of liquid carbon dioxide streams provides cooling for the system, and further energy efficiency is achieved by selective recycling of portions of gas streams, allowing for compact equipment and economical operation, while providing for high purity product streams of carbon dioxide.

Implementations described and claimed herein provide systems and methods for processing liquefied natural gas (LNG). In one implementation, a dry feed gas is received. The dry feed gas is chilled with clean vapor from a heavies removal column to form a chilled feed gas. The chilled feed gas is partially condensed into a vapor phase and a liquid phase. The liquid phase retains freezing components. The freezing components are extracted using a reflux stream in the heavies removal column. The freezing components are removed as a condensate. The vapor phase is compressed into a clean feed gas. The clean feed gas is free of the freezing components for downstream liquefaction.

The present invention relates to the extraction of gasoline from a gas G, with (a) a step of extracting gasoline from the gas to be treated comprising methanol GM obtained from step (d), (b) a step of separating said fluid GL1 partially condensed in step (a), producing a first aqueous liquid phase A1, a first liquid phase H1 of hydrocarbon(s) a gaseous phase G1 obtained from the gas G; (c) a step of contacting a portion of the gas G to be treated with said first aqueous liquid phase A1, producing a second aqueous liquid phase A2, a gaseous phase of gas to be treated comprising methanol GM′; (d) a step of mixing said gaseous phase of gas to be treated comprising methanol GM′ with the remainder of the gas G to be treated, producing a gas to be treated comprising methanol GM, (e) a step of stabilizing said first liquid phase H1 of hydrocarbon(s).

An apparatus for producing a purified, pressurized liquid carbon dioxide stream includes a distillation column (B) having packing (C) therein and a sump (D) below the packing, the distillation column in fluid communication with the liquid carbon dioxide supply tank for receiving the liquid carbon dioxide stream and the packing stripping volatile impurities from the liquid carbon dioxide stream; a heater (E) in contact with the liquid carbon dioxide stream in the sump (D) for vaporizing the liquid carbon dioxide stream in the sump; a vent in the distillation column (B) from which a first vaporized portion (G) of carbon dioxide vapor in the sump (D) is withdrawn from the distillation column: and a conduit (I) in fluid communication with the sump (D) and from which a second vaporized portion (H) of the carbon dioxide vapor in the sump is withdrawn into the conduit (I) to be introduced into the carbon dioxide vapor feed stream.

A system and method for removing nitrogen from natural gas using two fractionating columns, that may be stacked, and a plurality of separators and heat exchangers, with horsepower requirements that are 50-80% of requirements for prior art systems. The fractionating columns operate at different pressures. A feed stream is separated with a vapor portion feeding the first column to produce a first column bottoms stream that is split into multiple portions at different pressures and first column overhead stream that is split or separated into two portions at least one of which is subcooled prior to feeding the top of the second column. Optional heat exchange between first column and second column streams provides first column reflux and reboil heat for a second column ascending vapor stream. Three sales gas streams are produced, each at a different pressure.

A bio-renewable conversion process for making fuel from bio-renewable feedstocks is combined with a hydrogen production process that includes recovery of CO.sub.2. The integrated process uses a purge gas stream comprising hydrogen from the bio-renewable hydrocarbon production process in the hydrogen production process.

A system for removing nitrogen from a natural gas fluid feed stream includes a main heat exchanger that receives the natural gas fluid feed stream. A distillation column receives a cooled fluid stream from the main heat exchanger and features a return vapor outlet and a side vapor outlet port. The return vapor outlet provides nitrogen vapor to the main heat exchanger which is warmed therein. The side vapor outlet port provides vapor to the main heat exchanger and a reflux compressor receives and compresses the resulting fluid from the main heat exchanger. A reflux aftercooler receives and cools fluid from the reflux compressor, directs cooled fluid to the main heat exchanger and the resulting fluid is directed to a reflux separation device. The reflux separation device has a vapor outlet and a liquid outlet. The vapor outlet of the reflux separation device directs fluid to the main heat exchanger so that fluid is directed to the first reflux inlet port of the distillation column. The liquid outlet of the reflux separation device directs fluid to a second reflux inlet port of the distillation column.

Implementations described and claimed herein provide systems and methods for processing liquefied natural gas (LNG). In one implementation, a dry feed gas is received. The dry feed gas is chilled with clean vapor from a heavies removal column to form a chilled feed gas. The chilled feed gas is partially condensed into a vapor phase and a liquid phase. The liquid phase retains freezing components. The freezing components are extracted using a reflux stream in the heavies removal column. The freezing components are removed as a condensate. The vapor phase is compressed into a clean feed gas. The clean feed gas is free of the freezing components for downstream liquefaction.

A system and method for cooling a gas using a mixed refrigerant includes a compressor system and a heat exchange system, where the compressor system may include an interstage separation device or drum with no liquid outlet, a liquid outlet in fluid communication with a pump that pumps liquid forward to a high pressure separation device or a liquid outlet through which liquid flows to the heat exchanger to be subcooled. In the last situation, the subcooled liquid is expanded and combined with an expanded cold temperature stream, which is a cooled and expanded stream from the vapor side of a cold vapor separation device, and subcooled and expanded streams from liquid sides of the high pressure separation device and the cold vapor separation device, or combined with a stream formed from the subcooled streams from the liquid sides of the high pressure separation device and the cold vapor separation device after mixing and expansion, to form a primary refrigeration stream.