A method for treating produced water from a fraccing source is disclosed. The method first mixes nitrogen and produced water and feeds the mixture to a forward osmosis unit containing a semi-permeable membrane; carbon dioxide gas is then fed to the forward osmosis unit, therein creating a pressurized nitrogen side and a pressurized carbon dioxide side of the forward osmosis unit; concentrated produced water is recovered from the pressurized nitrogen side of the forward osmosis unit and fresh water is recovered from the pressurized carbon dioxide side of the forward osmosis unit.

A method for treating produced water from a fraccing source is disclosed. The method first mixes nitrogen and produced water and feeds the mixture to a forward osmosis unit containing a semi-permeable membrane; carbon dioxide gas is then fed to the forward osmosis unit, therein creating a pressurized nitrogen side and a pressurized carbon dioxide side of the forward osmosis unit; concentrated produced water is recovered from the pressurized nitrogen side of the forward osmosis unit and fresh water is recovered from the pressurized carbon dioxide side of the forward osmosis unit.

A functional polymer membrane contains a polymer compound having a constitutional unit represented by Formula I as a constitutional unit A, a constitutional unit represented by Formula I as a constitutional unit A, and a constitutional unit derived from a polyfunctional monomer having a C log P value of equal to or greater than 0.3 to less than 3.0 as a constitutional unit B.

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A composite membrane includes a hydrophobic porous membrane and a high water content hydrogel layer disposed on the surface of the hydrophobic porous membrane facing the hot end. The surface active agents contained in the wastewater at the hot end are blocked by the high water content hydrogel layer, thus the problem of pore wetting of the hydrophobic porous membrane can be prevented. Therefore, the membrane distillation technique can be utilized for processing wastewater containing surface active agents.

A composite membrane includes a hydrophobic porous membrane and a high water content hydrogel layer disposed on the surface of the hydrophobic porous membrane facing the hot end. The surface active agents contained in the wastewater at the hot end are blocked by the high water content hydrogel layer, thus the problem of pore wetting of the hydrophobic porous membrane can be prevented. Therefore, the membrane distillation technique can be utilized for processing wastewater containing surface active agents.

The invention relates to a membrane having a pore-free separating layer including a polymer mixture for separating simple alcohols and water from their mixtures with other organic fluids by means of pervaporation or vapor permeation. In accordance with the invention, the polymer mixture is composed of at least two polymer components which are taken from the group of polymer components which includes of the following polymer components: Polyvinyl alcohol, other polymers such as poly NN-dimethylaminoethyl methacrylate (poly DMAEMA), a copolymer of DMAEMA and N-vinyl pyrrolidone (NVP) or of DMAEMA and N-vinyl caprolactam (NVCL), a terpolymer of DMAE, NVP and NVCL or of vinyl acetate ethylene vinyl chloride or from vinyl chloride ethylene acrylic ester or from vinyl acetate vinyl chloride acrylic ester. The invention further relates to the use and to a method for manufacturing a membrane in accordance with the invention.

Disclosed is a porous hollow fiber membrane containing a polysulfone-based polymer as a main component, which has an asymmetric structure in which the inner surface side is dense and the outer surface side is coarse, wherein an average of a minor axis diameter of pores of an inner surface is 20 nm or more and 40 nm or less, an open porosity of the inner surface is 10% or more and 30% or less, and a polymer including a monocarboxylic acid vinyl ester unit is supported on at least one of the outer surface and the inner surface. The present invention provides a hollow fiber membrane which has excellent removing performance of substances to be separated such as viruses, and can be used as a separation membrane having high permeability even in a treatment under low pressure.

Disclosed is a porous hollow fiber membrane containing a polysulfone-based polymer as a main component, which has an asymmetric structure in which the inner surface side is dense and the outer surface side is coarse, wherein an average of a minor axis diameter of pores of an inner surface is 20 nm or more and 40 nm or less, an open porosity of the inner surface is 10% or more and 30% or less, and a polymer including a monocarboxylic acid vinyl ester unit is supported on at least one of the outer surface and the inner surface. The present invention provides a hollow fiber membrane which has excellent removing performance of substances to be separated such as viruses, and can be used as a separation membrane having high permeability even in a treatment under low pressure.

A membrane, in which the membrane is an ultrapure water membrane; a food and/or beverage processing membrane; a municipal water membrane; a peel oil recovery membrane; a (bio) refinery dewatering membrane; an oily wastewater (pre-)treatment membrane; a metal extraction membrane; a desalination membrane; and/or a protein fraction membrane. The membrane includes a porous substrate layer and an active layer arranged over at least a part of the substrate layer. The active layer is at least partially crosslinked and comprises a superhydrophilic agent. Also described is a method of producing the separation membrane.

A separation membrane that is an ultrapure water membrane; a food and/or beverage processing membrane; a municipal water membrane; a peel oil recovery membrane; a (bio) refinery dewatering membrane; an oily wastewater (pre-) treatment membrane; a metal extraction membrane; a desalination membrane; and/or a protein fraction membrane. The membrane includes a porous substrate layer and an active layer arranged over at least a part of the substrate layer. The active layer includes a hydrophilic agent and a superhydrophilic agent. Also described is a method of producing the separation membrane.