An environmental control system includes an air conditioning subsystem and a contaminant removal subsystem downstream of the environment to be conditioned. The contaminant removal subsystem includes: a first gas-liquid contactor-separator; a second gas-liquid contactor-separator; and a dehumidifier disposed either upstream of the first gas-liquid contactor-separator or downstream of the second gas-liquid contactor-separator.

A method for capturing carbon dioxide includes contacting a carbon dioxide lean gas mixture with water. One or more acid gas impurities may pass from the carbon dioxide lean gas mixture to the water to form a gas mixture and an aqueous effluent. The gas mixture is passed to a pressure swing adsorption system or a temperature swing adsorption system to increase a concentration of carbon dioxide in the gas mixture to form a carbon dioxide enriched gas mixture. The carbon dioxide enriched gas mixture is contacted with the aqueous effluent in a carbon dioxide scrubber. Carbon dioxide passes from the carbon dioxide enriched gas mixture to the aqueous effluent to form a stripped gas and acid gas enriched water. The acid gas enriched water is passed to a reactive rock formation. The one or more acid gas impurities and carbon dioxide are mineralized and permanently sequestered.

Various illustrative embodiments of a system and process for recovering high-quality biomethane and carbon dioxide product streams from biogas sources and utilizing or sequestering the product streams are provided. The system and process synergistically yield a biomethane product which meets gas pipeline quality specifications and a carbon dioxide product of a quality and form that allows for its transport and sequestration or utilization and reduction in greenhouse gas emissions. The system and process result in improved access to gas pipelines for products, an improvement in the carbon intensity rating of the methane fuel, and improvements in generation of credits related to reductions in emissions of greenhouse gases.

There is an absorbent mixture usable for the removal of sour gases from gas mixtures. The mixture has at least one organic base having a pK.sub.b (in water) less than or equal to 3.2; at least one alcoholic solvent of general formula R(OH).sub.n having a boiling temperature above or equal to 100° C. at ambient pressure, wherein R is a linear or branched saturated alkyl group having a number of carbon atoms between 2 and 20 and n is a whole number varying between 1 and 20; an aprotic polar solvent having a dielectric constant ε at 25° C. greater than or equal to 30, a viscosity μ at 25° C. less than or equal to 14 cP, preferably less than or equal to 12 cP; and a boiling temperature at normal pressure equal to or above 130° C. There is also a process for the removal of sour gases using the absorbent mixture.

A multi-stage process for the production of an ISO 8217 compliant Product Heavy Marine Fuel Oil from ISO 8217 compliant Feedstock Heavy Marine Fuel Oil involving a Reaction System composed of one or more reactor vessels selected from a group reactor wherein said one or more reactor vessels contains one or more reaction sections configured to promote the transformation of the Feedstock Heavy Marine Fuel Oil to the Product Heavy Marine Fuel Oil. The Product Heavy Marine Fuel Oil has a Environmental Contaminate level has a maximum sulfur content (ISO 14596 or ISO 8754) between the range of 0.05 mass % to 1.0 mass. A process plant for conducting the process for conducting the process is disclosed that can utilize a modular reactor vessel.

A CO.sub.2 separation/recover method in cement production exhaust gas has a step of harmful component removal that removes an acidic component and a harmful component from exhaust gas discharged from a cement production facility; and a step of CO.sub.2 separation and recover that separates and recovers CO.sub.2 by bringing the exhaust gas from which the acidic component and the harmful component are removed into contact with a CO.sub.2 absorption material, so that the acidic component and the harmful component are removed before separating and recovering CO.sub.2, resulting in deterioration of the absorbing ability of the CO.sub.2 absorption material being suppressed; and the cement production exhaust gas can be appropriately disposed.

A CO.sub.2 separation/recover method in cement production exhaust gas has a step of harmful component removal that removes an acidic component and a harmful component from exhaust gas discharged from a cement production facility; and a step of CO.sub.2 separation and recover that separates and recovers CO.sub.2 by bringing the exhaust gas from which the acidic component and the harmful component are removed into contact with a CO.sub.2 absorption material, so that the acidic component and the harmful component are removed before separating and recovering CO.sub.2, resulting in deterioration of the absorbing ability of the CO.sub.2 absorption material being suppressed; and the cement production exhaust gas can be appropriately disposed.

Absorption, or gas absorption, is a unit operation used in the chemical industries to separate gases by washing or scrubbing a gas mixture with a suitable liquid. Gas absorption is usually carried out in vertical countercurrent columns The solvent is fed in at the top of the absorber, the gas mixture from the bottom. We developed the process to get high yield and high efficiency.

A non-aqueous solvent system configured to remove acidic gas from a gas stream comprises a solution formed of a chemical absorption component and a physical absorption component. The chemical absorption component includes a nitrogenous base, wherein the nitrogenous base has a structure such that it reacts with a portion of the acidic gas. The physical absorption component includes an organic diluent that is non-reactive with the acidic gas and that has a structure such that it absorbs a portion of the acidic gas at a pressure above atmospheric pressure. The solvent system has a solubility with water of less than about 10 g of solvent per 100 mL of water.

One variation of a method for carbon sequestration includes: mixing ambient air including carbon dioxide and secondary gases with a working fluid to generate a first mixture; conveying the first mixture through a compressor to pressurize the first mixture from a first pressure to a second pressure greater than the first pressure to promote absorption of carbon dioxide into the working fluid; depositing the first mixture in a high-pressure vessel to generate an exhaust stream of secondary gases and a second mixture including carbon dioxide dissolved in the working fluid; conveying the second mixture through a turbine configured to extract energy and reduce pressure of the second mixture, from the second pressure to the first pressure, to promote desorption of carbon dioxide from the working fluid; transferring the second mixture into the low-pressure vessel; and releasing carbon dioxide, desorbed from the working fluid, from the low-pressure vessel for collection.