摘要:
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.
摘要:
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.
摘要:
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.
摘要:
Both power and H2 are produced from a gaseous mixture, comprising H2 and CO2, using first and second pressure swing adsorption (PSA) systems in series. The gaseous mixture is fed at super-atmospheric pressure to the first PSA system, which comprises adsorbent that selectively adsorbs CO2 at said pressure, and CO2 is adsorbed, thereby providing an H2-enriched mixture at super-atmospheric pressure. A fuel stream is formed from a portion of the H2-enriched mixture, which is combusted and the combustion effluent expanded to generate power. Another portion of the H2-enriched mixture is sent to the second PSA system, which comprises adsorbent that selectively adsorbs CO2 at super-atmospheric pressure, and CO2 is adsorbed, thereby providing a high purity H2 product. In preferred embodiments, the division of H2-enriched mixture between forming the fuel stream and being fed to the second PSA system is adjustable.
摘要:
According to an embodiment, a method of operating an oxy/fuel system and an oxy/fuel system circulate a support gas in the combustion system prior to activating at least one burner, produce the combustion fluid including CO2, wherein a level of the CO2 in the combustion fluid increases as a function of time, and continue production of the combustion fluid to exceed a predetermined level of the CO2 in the combustion fluid, for a period of time, the predetermined level being sufficient to permit the CO2 to be purified by a CO2 purification unit.
摘要:
SO2 and/or NOx are removed from gaseous CO2 at elevated pressure(s) in the presence of molecular oxygen and water and, when SO2 is to be removed, NOx, to convert SO2 to sulfuric acid and/or NOx to nitric acid. The sulfuric acid and/or nitric acid is/are then removed from the gaseous carbon dioxide to produce SO2-free, NOx-lean carbon dioxide gas. The invention has particular application in the removal of SO2 and/or NOx from carbon dioxide flue gas produced in an oxyfuel combustion process, for example, in a pulverized coal fired power station.
摘要:
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.
摘要:
A feed gas comprising CO2, H2S and H2 is treated to produce an H2-enriched product and a CO2 product. The feed gas is separated by pressure swing adsorption to provide a stream of the H2-enriched product, and two streams of sour gas depleted in H2 and enriched in H2S and CO2 relative to the feed gas. One of the streams of sour gas is processed in an H2S to elemental sulfur conversion system, in which H2S in the sour gas is converted to elemental sulfur order to obtain a stream of sweetened gas, from which the CO2 product is formed. The other of said streams of sour gas is processed in an oxidation system, in which H2S in the sour gas is oxidized to SOx (SO2 and SO3), the SO2 from the oxidation effluent or sulfuric/sulfurous acid obtained therefrom being introduced into the H2S to elemental sulfur conversion system as a reagent.
摘要:
Both power and H2 are produced from a gaseous mixture, comprising H2 and CO2, using first and second pressure swing adsorption (PSA) systems in series. The gaseous mixture is fed at super-atmospheric pressure to the first PSA system, which comprises adsorbent that selectively adsorbs CO2 at said pressure, and CO2 is adsorbed, thereby providing an H2-enriched mixture at super-atmospheric pressure. A fuel stream is formed from a portion of the H2-enriched mixture, which is combusted and the combustion effluent expanded to generate power. Another portion of the H2-enriched mixture is sent to the second PSA system, which comprises adsorbent that selectively adsorbs CO2 at super-atmospheric pressure, and CO2 is adsorbed, thereby providing a high purity H2 product. In preferred embodiments, the division of H2-enriched mixture between forming the fuel stream and being fed to the second PSA system is adjustable.
摘要:
Sulfur dioxide (SO2) is removed from carbon dioxide feed gas comprising SO2 as a contaminant by maintaining the carbon dioxide feed gas at an elevated pressure in contact with an alkaline sorbent for a period of time sufficient to react said alkaline sorbent with SO2. Where NOx, oxygen (O2) and water are also present, not only is the rate of reaction with the sorbent increased, but also additional SO2 is removed by conversion to sulfuric acid, and NOx is removed as nitric acid. The method has particular application in the removal of SO2 and NOx from flue gas produced by oxyfuel combustion of a hydrocarbon or carbonaceous fuel.