A method is described for removing carbon dioxide during Liquid Natural Gas production from natural gas at gas pressure letdown stations. The above method removes carbon dioxide from a Liquid Natural Gas production stream by using hydrocarbon fractions taken from a gas for consumption stream as a carbon dioxide stripping adsorption agent for a stripping column used to remove carbon dioxide.

A cryogenic method for capturing carbon dioxide in the gaseous emissions produced from the fossil-energy combustion of solid, liquid, or gaseous fossil fuels in a power generation installation employing an OxyFuel mode of combustion. The method includes: producing essentially pure carbon dioxide under elevated pressure and at near ambient temperatures in a Carbon-Dioxide Capture Component from the carbon-dioxide content of at least a part of the gaseous emissions produced from fossil-energy fueled combustion in the Oxyfuel mode of combustion; separating atmospheric air in an Air Separation Component into a stream of liquid nitrogen and a stream of high-purity oxygen; supplying low temperature, compressed purified air to a cryogenic air separation unit (cold box) within the Air Separation Component; collecting low temperature thermal energy from coolers employed within the Carbon-Dioxide Capture Component and the Air Separation Component; and converting the collected thermal energy to electricity within a Thermal-Energy Conversion Component.

The present disclosure provides method for clean methane startup of a distillation tower. The method includes maintaining a rectifier section and a lower section in the distillation tower, feeding stream to the lower section, directly feeding methane to at least one of the rectifier section and a rectifier section outlet line of the rectifier section when a contaminant concentration of the contaminant exiting as a vapor in an upper portion of the lower section is outside of a predetermined concentration and introducing the vapor from the lower section to the rectifier section when the contaminant concentration exiting the upper portion of the lower section is within the predetermined concentration.

A method and system for separating fluids in a distillation tower. The method may include feeding a stream to the distillation tower, wherein the stream includes carbon dioxide, reducing a carbon dioxide concentration of the stream received by the rectifier section by feeding a first cryogenic fluid to the controlled freeze zone section and accumulating rectifier section stream in at least one of a holding vessel and a sump of the rectifier section, and terminating reducing the carbon dioxide concentration when the carbon dioxide concentration of the stream travelling from the controlled freeze zone section to the rectifier section is less than or equal to a maximum carbon dioxide concentration. The first cryogenic fluid may comprise a substantially carbon-dioxide-free fluid.

A process and apparatus for producing a hydrogen-enriched product and recovering CO.sub.2 from an effluent stream from a hydrogen production process unit are described. The process utilizes a CO.sub.2 recovery system integrated with a PSA system that produces at least two product streams to recover additional hydrogen and CO.sub.2 from the tail gas stream of a hydrogen PSA unit in the hydrogen production process.

A process and apparatus for producing a hydrogen-enriched product and recovering CO.sub.2 from an effluent stream from a hydrogen production unit are described. The effluent from the hydrogen production unit, which comprises a mixture of gases comprising hydrogen, carbon dioxide, water, and at least one of methane, carbon monoxide, nitrogen, and argon, is sent to a PSA system that produces at least two product streams for separation. The PSA system that produces at least two product streams separates the gas mixture into a high-pressure hydrogen stream enriched in hydrogen, optionally a second gas stream containing the majority of the impurities, and a low-pressure tail gas stream enriched in CO.sub.2 and some impurities. The CO.sub.2-rich tail gas stream is compressed and sent to a CO.sub.2 recovery unit, where a CO.sub.2-enriched stream is recovered. The CO.sub.2-depleted overhead gas stream is recycled to the PSA system that produces at least two product streams.

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 process for separating carbon dioxide from a fluid containing carbon dioxide, NO.sub.2, and at least one of oxygen, argon, and nitrogen comprises the steps of separating at least part of the fluid into a carbon dioxide enriched stream, a carbon dioxide depleted stream comprising CO.sub.2 and at least one of oxygen, argon, and nitrogen and a NO.sub.2 enriched stream and recycling said NO.sub.2 enriched stream upstream of the separation step.

A set of process equipment for use in an enhanced oil recovery (EOR) process comprises first piping, a dehydrator, second piping, and a natural gas liquids recovery column. The first piping is configured to receive a wet carbon dioxide recycle stream from a recovery well. The dehydrator is configured to receive the wet carbon dioxide stream from the first piping and configured to dehydrate the wet carbon dioxide recycle stream using ethylene glycol to produce a dry carbon dioxide recycle stream. The second piping is configured to receive the dry carbon dioxide recycle stream from the dehydrator. The natural gas liquids recovery column is configured to receive the dry carbon dioxide recycle stream from the second piping and configured to separate the dry carbon dioxide recycle stream into a carbon dioxide reinjection stream and a natural gas liquids stream.

A method of integrating a fuel cell with a steam methane reformer is provided. The system includes at least one fuel cell including an anode and a cathode, and a steam methane reformer including a syngas stream, and a flue gas stream. The method includes introducing at least a portion of the flue gas stream to the cathode, thereby producing a CO2 depleted flue gas stream and introducing a hydrocarbon containing stream to the anode, thereby producing an electrical energy output and a carbon dioxide and hydrogen containing stream from the fuel cell.