30 results about "Membrane gas separation" patented technology

A method for forming a synthesis gas with a tailored hydrogen/carbon dioxide ratio that is optimized for use in one or more predetermined downstream processes wherein membrane gas separation is employed to form a hydrogen rich stream and a separate synthesis gas product which product has said tailored ratio.

The present invention is directed toward a method for purifying a natural gas stream comprising: 1) removing the bulk of CO₂ by at least one non-membrane gas separation means; and 2) removing oxygen and other impurities by at least one additional gas separation means, wherein the final natural gas product has low level of CO₂ and oxygen.

A process involving membrane-based gas separation and power generation, specifically for controlling carbon dioxide emissions from gas-fired power plants. The process includes a compression step, a combustion step, and an expansion/electricity generation step, as in traditional power plants. The process also includes a sweep-driven membrane separation step and a carbon dioxide removal or capture step. The carbon dioxide removal step is carried out on a portion of gas from the compression step.

A process for removing carbon dioxide or nitrogen from gas, especially natural gas. The process uses three membrane separation stages without compression between the second and third stages.

A process for regenerating a facilitated-transport membrane, such as a gas separation membrane, that contains an ionic complexing agent, and that has lost performance as a result of reduction of at least some of the ions to a less charged or uncharged form. The process involves exposing the membrane to an oxidizing agent, such as hydrogen peroxide. The invention also includes membranes that have been regenerated in this way, and their use, particularly for separating light olefins from light paraffins by membrane gas separation.

Gas separation membranes formed from polyether-urethane or polyether-urea block copolymers are useful for separating gases from gas mixtures. The membranes and processes are especially suited for separating polar gases from mixtures that contain polar and non-polar species. The novel membranes exhibit good permeability and permselectivity, as well as durability, making them well suited for industrial applications such as removal of acid gases from natural gas and removal of carbon dioxide from synthesis gas.

Gas separation membrane compositions including at least one crosslinked polymer, gas separation membranes made of such compositions, methods for making such gas separation membranes, and methods of using such membranes to separate gases are described. In one embodiment, the crosslinked polymer includes polyarylene ethers (PAE).

A gas separation process for treating a gas stream containing vapors of condensable components. The process includes two membrane separation steps, the second step using membranes of lower selectivity than the first step. Advantageously, the first membrane separation step may be carried out outside the pressure-ratio-limited region and the second membrane separation step may be carried out within the pressure-ratio-limited region. The second residue stream is a desired product of the process, and the process is particularly useful for applications where the target concentration of component A in this product is low, such as below 1-2 vol %.

The invention relates to the field of membrane gas separation. A method of removing components of gas mixtures which is based on passing the components of a gas mixture through a nanoporous membrane and subsequently selectively absorbing them with a liquid absorbent that is in contact with the nanoporous membrane, wherein to prevent the gas from getting into the liquid phase of the absorbent and the liquid phase of the absorbent from getting into the gas phase, a nanoporous membrane with homogeneous porosity (size distribution less than 50%) and a pore diameter in the range of 5-500 nm is used, and the pressure differential between the gas phase and the liquid absorbent is kept below the membrane bubble point pressure. An acid gas removal performance of more than 0.3 nm³/(m² hour) in terms of CO₂ is achieved at a hollow-fiber membrane packing density of up to 3200 m²/m³, which corresponds to a specific volumetric performance of acid gas removal of up to 1000 nm³ (m³ hour). The technical result is that of providing effective extraction of undesirable components from natural and process gas mixtures.

Apparatus, methods and uses for separating gas mixtures of at least two different gases under magnetic field and employing a membrane are described.

Separation of a gas mixture comprising first and second gases may be improved using four stages of gas separation membrane modules that includes the additional techniques of cooling the feed gas stream that is fed to the first (feed) stage and using a portion of the fourth (second permeate) stage retentate as a sweep gas on the permeate stage.

Separation of a gas mixture comprising first and second gases may be improved using two cascaded stages of gas separation membrane modules that includes the additional techniques of cooling the feed gas stream that is fed to the feed stage and using a portion of the feed stage retentate as a sweep gas on the feed stage.

The invention relates to the field of membrane gas separation and can be used for the energy-efficient fractionation of hydrocarbon mixtures, including separation and drying of natural and associated petroleum gases. Proposed is a method of fractionating mixtures of low molecular weight hydrocarbons which is based on the capillary condensation of the components of a mixture in the pores of microporous membranes with uniform porosity and a pore diameter in a range of 5 to 250 nm, wherein, for capillary condensation, the temperature of the membrane and the pressure on the permeate side are kept below the temperature and the pressure of the feed mixture such that the equilibrium pressure of the saturated vapors of the separated components on the permeate side is lower than the partial pressure of the components in the feed stream. This method makes it possible to significantly increase membrane permeability with respect to condensable components (over 500 m³/(m²·atm·h) for n-butane), and also component separation factors (the n-C₄H₁₀/CH₄ separation factor is greater than 60 for a mixture having an associated petroleum gas composition), while also making it possible to dispense with deep cooling of the gas stream fed to a membrane module, and to carry out gas separation under insignificant cooling of the membrane on the permeate side (down to −50° C.) For more effective gas separation, permeate is collected in a liquid state. A technical effect of the invention resides in providing a method that makes it possible to efficiently remove high-boiling hydrocarbons (C₃-C₆) from natural gas and associated petroleum gases, as well as to obtain gas mixtures with a constant composition.

The invention provides an electronegative gas electromigration membrane separation method. To-be-separated electronegative and non-electronegative mixed gas is filled into a gas separation device; electrons are generated by utilizing an electron generator in the gas separation device; after electronegative gas in the mixed gas is collided with the electrons, stable negative ions or negative ion clusters are generated; the negative ions or the negative ion clusters enter an electric field consisting of a cathode and an anode in the gas separation device together with a gas flow; a gas separation membrane is arranged in the electric field closed to the inside of the anode; the negative ions or the negative ion clusters permeate and pass through the gas separation membrane under the pushing action of electric field force and a concentration difference between two sides of the gas separation membrane; and the gas passing through the gas separation membrane is further collected, so as to implement separation of the electronegative and non-electronegative mixed gas. By adopting the method provided by the invention, system resistance of membrane gas separation can be greatly reduced; themethod is particularly applicable to the separation of electronegative gas such as O2, H2S, SO2 and the like, and non-electronegative gas such as N2, H2 and the like; and low-energy-consumption high-efficiency separation of the gas can be implemented.