30 results about "Membrane gas separation" patented technology

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 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 method is proposed for operating a plant for purifying a high-pressure gas mixture from easily permeating components, which plant comprises membrane gas separating units having a high-pressure chamber and a low-pressure chamber with a selectively permeable membrane therebetween, in which method the low-pressure chamber of at least one membrane gas separating unit is continuously flushed with purified gas mixture (semi-finished product or product), wherein the pressure difference between the aforementioned chambers of the membrane gas separating unit and, likewise, the flow rate of the purified gas mixture used for flushing are maintained so that the amount of each easily permeating component in the product does not exceed the desired values. The proposed method makes it possible to purify a raw material (high-pressure gas mixture) from one or more easily permeating components simultaneously (in particular helium, hydrogen sulphide, mercaptans, carbon dioxide, water and / or heavy hydrocarbons), increase purification efficiency (i.e. the ratio between the total area of the selectively permeable membrane in the plant, the productivity of said membrane and the specific energy consumption of the gas separation process), and provide the possibility of using (treating or preparing) raw material with a higher content of easily permeating components.

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).

The invention relates to a self-polymerized microporous polyimide gas separation membrane and its preparation method and application, belonging to the technical field of membrane gas separation, in order to prepare and synthesize a polymer gas separation membrane with high selectivity and high permeability , to meet the requirements of practical industrial applications. In the present invention, the main chain of self-polymerized microporous polyimide contains a ladder structure, which increases the distance between polymer chains, facilitates the separation and diffusion of gases, and reduces the hydrogen bonds between polymer molecules. function, improve the solubility of the polymer, the present invention utilizes two kinds of diamines with ladder structure and dianhydrides with different structures to prepare through homopolymerization or copolymerization reaction. In the present invention, two kinds of ladder-shaped diamine monomers containing oxa-naphthalene structure were synthesized for the first time, and the trapezoidal self-polymerizing microporous polyimide polymer containing oxa-naphthene structure was synthesized through polycondensation reaction, which has good thermal stability and Mechanical properties, high selectivity to oxygen / nitrogen, can meet the practical application of gas separation.

The invention relates to an asymmetric electrostatic field coupling membrane gas separation device which comprises a raw material chamber, a permeating chamber, a membrane and an electrode, wherein the electrode can be used for generating an asymmetric electrostatic field; the electrode comprises a flat electrode and a needle electrode; a 101-104V direct current voltage is applied to the electrode; the raw gas containing polar gas molecules enters into the raw material chamber; under the dual action of chemical potential gradient and electric potential gradient of the asymmetric electrostatic field, the raw gas spreads and permeates through the membrane at a speed higher than the speed under the existence of pure chemical potential gradient, thereby forming the penetrating gas and flowing from the permeating chamber; and the remaining gas flows from the raw material chamber, thereby separating the raw gas. The invention also relates to an asymmetric electrostatic field coupling membrane gas separation method.

The invention relates to membrane gas separation, in particular to a method of fractionating mixtures of low molecular weight hydrocarbons based on the capillary condensation of the mixture components in the pores of microporous membranes having uniform porosity and a pore diameter 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. The method provides significantly increasing membrane permeability with respect to condensable components, and also component separation factors, while also allowing to avoid 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.). The invention provides for energy-efficient fractionation of hydrocarbon mixtures, including separation and drying of natural and associated petroleum gases.

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

The object of the present invention is to provide a device that can not only separate and obtain high-purity oxygen from air etc. by using a PSA gas separation device, but also continuously and efficiently separate and obtain high-purity nitrogen from the desorption gas continuously supplied by the PSA gas separation device. methods and systems. The invention comprises a PSA gas separation process implemented by a PSA gas separation device (1) and a membrane gas separation process implemented by a membrane gas separator (2). In the PSA gas separation process, oxygen-enriched gas and mainly nitrogen-containing but also Oxygen-containing desorbed gas. In the membrane gas separation process, the permeate side of the gas separation membrane (2A), which preferentially permeates oxygen, is depressurized to a pressure lower than atmospheric pressure, and the desorbed gas is separated into permeate gas by the gas separation membrane (2A). Gas permeated by the gas separation membrane (2A) and non-permeated gas (nitrogen-enriched gas) not permeated by the gas separation membrane (2A).

The invention provides a method for improving the gas separation performance of a supported MOF membrane by using a polymer coating. A layer of polymer coating is coated on the surface of the MOF membrane, which can repair the defects of the MOF membrane; The material coating can effectively prevent the flexibility of the MOF framework and limit the expansion of its pore size, thereby effectively improving the gas separation performance. In addition, the externally applied polymer coating can significantly improve the hydrothermal stability of the MOF membrane, and the coating also effectively protects the brittleness of the MOF membrane itself. The method for repairing the MOF membrane by using the polymer coating mentioned in the present invention has wide application value in the field of gas separation.

The invention relates to a preparation method and application of a phosphoric acid-treated Tröger`s Base polymer gas separation membrane, which belongs to the technical field of membrane gas separation and solves the separation selectivity of existing separation membranes for light gases such as hydrogen and carbon dioxide Low, low separation efficiency technical problems. The solution is: First, use the rigid skeleton structure of Tröger`s base to obtain a large free volume and increase the efficiency of gas transmission. After phosphoric acid treatment, use the interaction between N on the main chain and phosphoric acid to maintain phosphoric acid in the polymerization Stability in the material, improve the selectivity of hydrogen to carbon dioxide. The selectivity can be adjusted by changing the acid treatment conditions of the polymer. Experiments have shown that the performance of the treated membrane exceeds the current 2008 Robeson upper limit at room temperature and high temperature.

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.

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.