Abstract: A process for producing compressed hydrogen gas, said process comprising electrolysing water to produce hydrogen gas and compressing said hydrogen gas in a multistage compression system to produce compressed hydrogen gas. The multistage compression system comprises at least one centrifugal compression stage, and the hydrogen gas is fed to the centrifugal compression stage at a pre-determined feed temperature and pressure and having a pre-determined relative humidity. The process further comprises adding water and heat to the hydrogen gas upstream of the centrifugal compression stage, as required, to humidify the hydrogen gas to the pre-determined relative humidity.

Abstract: A process for producing compressed hydrogen gas including: electrolysing water to produce hydrogen gas, and compressing the hydrogen gas in a multistage compression system including: a centrifugal compression stage and a recycle system for recycling a portion of the hydrogen gas from a product end to a feed end of the centrifugal compression stage; wherein hydrogen gas feed is fed to the feed end at a pre-determined feed temperature and pressure and mole fraction of water; wherein a portion of the hydrogen gas is removed from the product end, reduced in pressure in the recycle system to the pre-determined feed pressure and is then recycled to form at least part of the hydrogen gas feed to the centrifugal compression stage; and further including cooling hydrogen gas comprising the reduced pressure hydrogen gas such that the water mole fraction in the hydrogen gas feed is at the pre-determined water mole fraction.

Abstract: Recovery of hydrogen from an ammonia cracking process in which the cracked gas is purified in a PSA device is improved by using a membrane separator on the PSA tail gas.

Abstract: A method for supplying hydrogen gas for consumption in at least one downstream process, the method comprising: electrolysing water to provide hydrogen gas; compressing the hydrogen gas in a multistage compression system to provide compressed hydrogen gas; and feeding at least a portion of the compressed hydrogen gas to the downstream process(es); wherein the multistage compression system comprises at least one centrifugal compression stage; wherein the hydrogen gas is dosed with nitrogen gas upstream of the centrifugal compression stage(s); and wherein the nitrogen gas is present in the compressed hydrogen gas when fed to the downstream process(es).

Abstract: A process for producing compressed hydrogen gas including: electrolysing water to produce hydrogen gas, and compressing the hydrogen gas in a multistage compression system including: a centrifugal compression stage and a recycle system for recycling a portion of the hydrogen gas from a product end to a feed end of the centrifugal compression stage; wherein hydrogen gas feed is fed to the feed end at a pre-determined feed temperature and pressure and mole fraction of water; wherein a portion of the hydrogen gas is removed from the product end, reduced in pressure in the recycle system to the pre-determined feed pressure and is then recycled to form at least part of the hydrogen gas feed to the centrifugal compression stage; and further including cooling hydrogen gas comprising the reduced pressure hydrogen gas such that the water mole fraction in the hydrogen gas feed is at the pre-determined water mole fraction.

Abstract: A process for producing compressed hydrogen gas, said process comprising electrolysing water to produce hydrogen gas and compressing said hydrogen gas in a multistage compression system to produce compressed hydrogen gas. The multistage compression system comprises at least one centrifugal compression stage, and the hydrogen gas is fed to the centrifugal compression stage at a pre-determined feed temperature and pressure and having a pre-determined relative humidity. The process further comprises adding water and heat to the hydrogen gas upstream of the centrifugal compression stage, as required, to humidify the hydrogen gas to the pre-determined relative humidity.

Abstract: A method for supplying hydrogen gas for consumption in at least one downstream process, the method comprising: electrolysing water to provide hydrogen gas; compressing the hydrogen gas in a multistage compression system to provide compressed hydrogen gas; and feeding at least a portion of the compressed hydrogen gas to the downstream process(es); wherein the multistage compression system comprises at least one centrifugal compression stage; wherein the hydrogen gas is dosed with nitrogen gas upstream of the centrifugal compression stage(s); and wherein the nitrogen gas is present in the compressed hydrogen gas when fed to the downstream process(es).

Abstract: A helium-containing stream is recovered from a natural gas feed using a membrane followed by multiple distillation steps. Refrigeration is provided by expanding a bottoms liquid with a higher nitrogen content than the feed, achieving a lower temperature in the process. The helium-enriched vapor is then purified and the helium-containing waste stream is recycled to maximize recovery and reduce the number of compressors needed. The helium-depleted natural gas stream can be returned at pressure for utilization or transportation.

Abstract: A crude helium stream is recovered from a natural gas feed by distillation. Refrigeration from expanding a portion of the bottoms liquid is used to partially condense the helium-enriched overhead vapor and generate a crude helium vapor and a helium-containing liquid stream that is recycled to the distillation column to maximize helium recovery. The helium-depleted natural gas stream can be returned at pressure for utilization or transportation.

Abstract: A helium-containing stream is recovered from a natural gas feed using a membrane followed by multiple distillation steps. Refrigeration is provided by expanding a bottoms liquid with a higher nitrogen content than the feed, achieving a lower temperature in the process. The helium-enriched vapor is then purified and the helium-containing waste stream is recycled to maximize recovery and reduce the number of compressors needed. The helium-depleted natural gas stream can be returned at pressure for utilization or transportation.

Abstract: The power required to recover C3+ hydrocarbons from crude carbon dioxide comprising C1+ hydrocarbons and hydrogen sulfide may be reduced by distilling the crude carbon dioxide to produce carbon dioxide-enriched overhead vapor and C3+ hydrocarbon-enriched bottoms liquid such that the hydrogen sulfide is rejected with the overhead vapor. Power consumption reductions may be achieved by incorporating a heat pump cycle using carbon dioxide vapor as working fluid to provide at least a part of the refrigeration duty and using a side reboiler to reduce the bottom reboiler duty. Where the bottoms liquid is further processed to produce “lighter” and “heavier” hydrocarbon fractions, the process enables optimization of upgrading crude oil on the basis of API gravity, Reid Vapor pressure and/or viscosity.

Abstract: In a process for separating at least one “heavy” impurity such as hydrogen sulfide from crude carbon dioxide comprising significant quantities of at least one “light” impurity such as non-condensable gases, involving at least one heat pump cycle using carbon dioxide-containing fluid from the process as the working fluid, the “light” impurity is removed from the crude carbon dioxide and carbon dioxide is subsequently recovered from the removed “light” impurity, thereby improving overall carbon dioxide recovery and efficiency in terms of energy consumption.

Abstract: Helium can be recovered from nitrogen-rich natural gas at high pressure with low helium loss by cryogenic distillation of the natural gas after pre-treatment of the gas to remove incompatible impurities and then recovery of natural gas liquid (NGL) from the pre-treated gas by distillation. Overall power consumption may be reduced, particularly if the feed to the helium recovery column system is at least substantially condensed by indirect heat exchange against a first portion of nitrogen-enriched bottoms liquid at first pressure, and a second portion of nitrogen-enriched bottoms liquid at a second pressure that is different from the first pressure.

Abstract: Overall power consumption in a cryogenic distillation process for recovering helium from nitrogen-rich gases comprising helium may be reduced if the feed to the distillation column system is at least substantially condensed by indirect heat exchange against a first bottoms liquid at first pressure, and a second bottoms liquid at a second pressure that is different from the first pressure.

Abstract: Systems and methods are provided for recovering helium from a feed comprising helium, carbon dioxide, and at least one intermediate component having a volatility between those of helium and carbon dioxide. In particular, processes of the present invention comprise separating the carbon dioxide and the components of intermediate volatility from the helium at a temperature greater than ?82.7° C. to form a helium-rich product stream, wherein the concentration of at least one of the intermediate components in the helium-rich product stream is lower than its concentration in the feed stream, and wherein at least part of the separation is effected by contacting a vapor with a liquid.

Abstract: Helium can be recovered from nitrogen-rich natural gas at high pressure with low helium loss by cryogenic distillation of the natural gas after pre-treatment of the gas to remove incompatible impurities and then recovery of natural gas liquid (NGL) from the pre-treated gas by distillation. Overall power consumption may be reduced, particularly if the feed to the helium recovery column system is at least substantially condensed by indirect heat exchange against a first portion of nitrogen-enriched bottoms liquid at first pressure, and a second portion of nitrogen-enriched bottoms liquid at a second pressure that is different from the first pressure.

Abstract: Overall power consumption in a cryogenic distillation process for recovering helium from nitrogen-rich gases comprising helium may be reduced if the feed to the distillation column system is at least substantially condensed by indirect heat exchange against a first bottoms liquid at first pressure, and a second bottoms liquid at a second pressure that is different from the first pressure.

Abstract: The power required to recover C3+ hydrocarbons from crude carbon dioxide comprising C1+ hydrocarbons and hydrogen sulfide may be reduced by distilling the crude carbon dioxide to produce carbon dioxide-enriched overhead vapor and C3+ hydrocarbon-enriched bottoms liquid such that the hydrogen sulfide is rejected with the overhead vapor. Power consumption reductions may be achieved by incorporating a heat pump cycle using carbon dioxide vapor as working fluid to provide at least a part of the refrigeration duty and using a side reboiler to reduce the bottom reboiler duty. Where the bottoms liquid is further processed to produce “lighter” and “heavier” hydrocarbon fractions, the process enables optimization of upgrading crude oil on the basis of API gravity, Reid Vapor pressure and/or viscosity.

Abstract: Sulfur dioxide (SO2) is removed from a carbon dioxide feed gas by maintaining the feed gas at elevated pressure(s) in the presence of oxygen (O2), water and NOx for a period of time sufficient to convert SO2 to sulfuric acid and NOx to nitric acid and produce SO2-depleted, NOx-lean carbon dioxide gas. The invention resides in separating the sulfuric and nitric acids from said SO2-depleted, NOx-lean carbon dioxide gas, and then neutralizing the acids by reaction with an alkaline sorbent in an acid/sorbent reactor system to produce sorbent-derive sulfate. The method has particular application in the removal of SO2 and NOx from flue gas produced by oxyfuel combustion of a carbonaceous fuel.

Abstract: In a process for separating “heavy” impurities such as hydrogen sulfide from crude carbon dioxide comprising significant quantities of “light” impurities such as non-condensable gases, involving at least one heat pump cycle using as working fluid a fluid from the “heavy” impurity separation, the “light” impurities are removed from carbon dioxide-enriched gas generated in the “heavy” impurity separation. The carbon dioxide-enriched gas, or a compressed carbon dioxide-enriched gas produced therefrom, is at least partially condensed by indirect heat exchange against intermediate liquid also generated in the “heavy” impurity separation. Total and specific energy consumption is reduced compared to conventional processes in which “light” impurities are removed from carbon dioxide product gas.