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 of nitrogen and methane. The feed is separated in a first separator to form helium-enriched stream and a CO2-enriched stream. The helium-enriched stream is separated in a pressure swing adsorption unit to form a helium-rich product stream and a helium-lean stream. At least a portion of the helium-lean stream is recycled to the first separator with the feed. In some embodiments, a membrane separation unit is used to enhance helium recovery.

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: Systems and methods are provided for recovering helium from a feed comprising helium, carbon dioxide, and at least one of nitrogen and methane. The feed is separated in a first separator to form helium-enriched stream and a CO2-enriched stream. The helium-enriched stream is separated in a pressure swing adsorption unit to form a helium-rich product stream and a helium-lean stream. At least a portion of the helium-lean stream is recycled to the first separator with the feed. In some embodiments, a membrane separation unit is used to enhance helium recovery.

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 “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.

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: Impurities that are less volatile than carbon dioxide, e.g. hydrogen sulfide, are removed from crude carbon dioxide by processes involving distillation of said crude carbon dioxide in a distillation column system operating at super-atmospheric pressure(s) to produce carbon dioxide-enriched overhead vapor and bottoms liquid enriched with said impurities. Where such processes involve a single heat pump cycle, significant savings in power consumption are realized when the distillation column system is re-boiled by at least partially vaporizing liquid in or taken from an intermediate location in the column system.

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: Impurities that are less volatile than carbon dioxide, e.g. hydrogen sulphide, are removed from crude carbon dioxide by processes involving sub-ambient distillation of said crude carbon dioxide in a distillation column system operating at super-atmospheric pressure(s) to produce carbon dioxide-enriched overhead vapour and bottoms liquid enriched with said impurities. Where such processes involve at least one heat pump cycle, significant savings in power consumption are realised when the process uses more than one recycle pressure in the heat pump cycle(s).

Abstract: A system and process for liquefying a gas, comprising introducing a feed stream into a liquefier comprising at least a warm expander and a cold expander; compressing the feed stream in the liquefier to a pressure greater than its critical pressure and cooling the compressed feed stream to a temperature below its critical temperature to form a high pressure dense-phase stream; removing the high pressure dense-phase stream from the liquefier, reducing the pressure of the high pressure dense-phase stream in an expansion device to form a resultant two-phase stream and then directly introducing the resultant two-phase stream into a storage tank; and combining a flash portion of the resultant two-phase stream with a boil-off vapor from a liquid in the storage tank to form a combined vapor stream, wherein the temperature of the high pressure dense-phase stream is lower than the temperature of a discharge stream of the cold expander.

Abstract: Refrigeration duty in a carbon dioxide purification unit (CPU) operating at elevated pressure and sub-ambient temperature can be provided in at least a first part by indirect heat exchange against at least latent heat of at least one liquid first refrigerant, preferably carbon dioxide liquid(s) produced in the CPU, thereby typically evaporating the liquid(s), and a second part by indirect heat exchange with sensible heat energy alone of a second refrigerant. The second refrigerant may be nitrogen gas imported from an integrated cryogenic air separation unit (ASU) or carbon dioxide liquid exported from the CPU, cooled and returned to the CPU. One advantage is that total power consumption of the CPU and an integrated ASU is reduced.

Abstract: An open brayton cycle power generation system is enabled and improved by integration of an energy storage system utilizing cryogenic storage of atmospheric gas. A particular improved system is an open brayton cycle power generation system in which the heating source is Concentrating Solar Power. Multiple embodiments are described which permit various modes of operation and improved overall efficiency.

Abstract: Disclosed are a method and system involving pressurizing an atmospheric gas stream to form at least a compressed atmospheric gas stream, directing the compressed atmospheric gas stream to a first regenerator for cooling, pressurizing to above a second predetermined pressure to form at least a supercritical atmospheric gas stream, directing the supercritical atmospheric gas stream to a second regenerator for cooling, reducing pressure to form at least a liquefied atmospheric gas stream, selectively storing the liquefied atmospheric gas stream, pressurizing the liquefied atmospheric gas stream to form at least a pressurized liquefied atmospheric gas stream, heating the pressurized liquefied atmospheric gas stream in the second regenerator to form at least a heated stream, expanding the heated stream to form at least a medium pressure atmospheric gas stream, directing the medium pressure atmospheric gas stream to the first regenerator, and heating the medium pressure atmospheric gas stream in the first regenerat

Abstract: Disclosed is a method and a system. The method and system involve compressing an atmospheric gas stream to form a supercritical atmospheric gas stream, forming at least a first stream from the supercritical atmospheric gas stream, directing the first stream to a regenerator for cooling to form a first cooled stream, directing the first cooled stream from the regenerator, expanding the first cooled stream to form a liquefied atmospheric gas stream, storing at least a portion of the liquefied atmospheric gas stream, pressurizing at least a portion of the stored portion of the liquefied atmospheric gas stream, and heating at least a portion of a pressurized liquefied atmospheric gas stream in the regenerator. In the method and system, refrigeration below the critical temperature of the atmospheric gas is directly or indirectly provided to at least one portion of the system from a non-combustible source.

Abstract: NO2 may be removed from a carbon dioxide feed gas comprising NOx and at least one “non-condensable” gas as contaminants by passing the feed gas at a first elevated pressure through a first adsorption system that selectively adsorbs at least NO2 to produce at least substantially NO2-free carbon dioxide gas. The adsorption system is at least partially regenerated using a carbon dioxide-rich gas recovered from the substantially NO2-free carbon dioxide gas after purification. The invention has particular application in removing NOx and water from flue gas generated by oxyfuel combustion.