Abstract: Conventional porous membranes have a mesh structure having a relatively large pore diameter in order to improve the removability of a relatively large component such as a virus. When a contaminative liquid to be filtered is filtered, contaminants are easily accumulated in the porous membranes, clogging or the like occurs in the porous membranes, and contamination of the porous membranes easily occurs. Accordingly, an object is to provide a porous membrane having high contamination resistance and high-precision removability. To achieve the object, provided is a porous membrane including, in at least one surface, a surface portion spanning 10 ?m in thickness from the surface, being denser than an inner portion, and having a removal rate T of dextran having a weight-average molecular weight of 40,000 Da of 60 to 95%, in which a number of surface pores per unit area observed on the surface of the surface portion is 200 pores/?m2 to 2,000 pores/?m2.

Abstract: The present invention relates to a porous membrane including a polymer including a polyvinylidene fluoride-based resin as a main component, and a branched polyvinylidene fluoride-based resin as the polyvinylidene fluoride-based resin, in which the polymer has a value of a of 0.32 to 0.41 and a value of b of 0.18 to 0.42, each of which is determined by approximation according to the formula 1 below from a radius of gyration <S2>1/2 and an absolute molecular weight Mw of the polymer which are measured by GPC-MALS (gel permeation chromatograph equipped with a multi-angle light scattering detector). <S2>1/2=bMwa (Formula 1).

Abstract: The present invention relates to a hollow-fiber membrane module including: a hollow-fiber membrane bundle including a plurality of hollow-fiber membranes bundled in a potting part; a housing enclosing the hollow-fiber membrane bundle; and a protective member contacting with an outer surface of the potting part and continuously covering the outer surface, in which the protective member has a notched part through which one end of the protective member communicates with another end in a longitudinal direction of the hollow-fiber membrane bundle.

Abstract: The present invention relates to a method of filtering an oil, the method including the following steps (A) and (B): (A) allowing a hydrophobic gas to permeate through a porous membrane including a hydrophobic polymer as a main component; and (B) allowing an oil to permeate through the porous membrane, in which the step (B) is performed after the hydrophobic gas that has permeated through the porous membrane is confirmed to have a relative humidity of 0 to 60% in the step (A).

Abstract: The present invention relates to a method of filtering an oil, the method including the following steps (A) and (B): (A) allowing a hydrophobic gas to permeate through a porous membrane including a hydrophobic polymer as a main component; and (B) allowing an oil to permeate through the porous membrane, in which the step (B) is performed after the hydrophobic gas that has permeated through the porous membrane is confirmed to have a relative humidity of 0 to 60% in the step (A).

Abstract: The present invention relates to a porous membrane including a polymer including a polyvinylidene fluoride-based resin as a main component, and a branched polyvinylidene fluoride-based resin as the polyvinylidene fluoride-based resin, in which the polymer has a value of a of 0.32 to 0.41 and a value of b of 0.18 to 0.42, each of which is determined by approximation according to the formula 1 below from a radius of gyration <S2>1/2 and an absolute molecular weight Mw of the polymer which are measured by GPC-MALS (gel permeation chromatograph equipped with a multi-angle light scattering detector).

Abstract: The present invention relates to a composite porous hollow-fiber membrane including a first layer and a second layer which each include a fluororesin-based polymer, in which at least a part of molecular chains of the fluororesin-based polymer is oriented in a longitudinal direction of the composite porous hollow-fiber membrane, the molecular chains of the fluororesin-based polymer have a degree of orientation it in the longitudinal direction of the composite porous hollow-fiber membrane of 0.4 or higher but less than 1.0, the degree of orientation it being calculated with the specific formula.

Abstract: The present invention relates to a hollow-fiber membrane module including: a hollow-fiber membrane bundle including a plurality of hollow-fiber membranes bundled in a potting part; a housing enclosing the hollow-fiber membrane bundle; and a protective member contacting with an outer surface of the potting part and continuously covering the outer surface, in which the protective member has a notched part through which one end of the protective member communicates with another end in a longitudinal direction of the hollow-fiber membrane bundle.

Abstract: The present invention provides a hollow fiber membrane module that can effectively resolve the accumulation of suspended solids within the membrane module, lower running costs, and also operate stably. The present invention relates to a hollow fiber membrane molecule provided with: a cylindrical case having a first end and a second end in the direction of height; a plurality of hollow fiber membranes accommodated within the cylindrical case; and a first potting part accommodated within the cylindrical case and attaching the plurality of hollow fiber membranes together such that the end parts of the plurality of hollow membrane fibers at a first end side of the cylindrical case are open. The hollow fiber membranes are porous hollow fiber membranes having a breaking strength of 23 MPa, and the hollow membrane module has a membrane area per unit volume of 800-3700 m2/m3. The filling fraction for the hollow fiber membranes in a cross-section orthogonal to the direction of height of the cylindrical case is 25-38%.

Abstract: The present invention relates to a composite porous hollow-fiber membrane including a first layer and a second layer which each include a fluororesin-based polymer, in which the first layer has a columnar texture oriented in a longitudinal direction of the composite porous hollow-fiber membrane, the columnar texture has an average value v of a Raman orientation parameter calculated with the specific formula, and the second layer has a three-dimensional network texture and has an average surface-pore diameter of 5.0 nm to 5.0 ?m.

Abstract: The present invention provides a hollow fiber membrane module that can effectively resolve the accumulation of suspended solids within the membrane module, lower running costs, and also operate stably. The present invention relates to a hollow fiber membrane molecule provided with: a cylindrical case having a first end and a second end in the direction of height; a plurality of hollow fiber membranes accommodated within the cylindrical case; and a first potting part accommodated within the cylindrical case and attaching the plurality of hollow fiber membranes together such that the end parts of the plurality of hollow membrane fibers at a first end side of the cylindrical case are open. The hollow fiber membranes are porous hollow fiber membranes having a breaking strength of 23 MPa, and the hollow membrane module has a membrane area per unit volume of 800-3700 m2/m3. The filling fraction for the hollow fiber membranes in a cross-section orthogonal to the direction of height of the cylindrical case is 25-38%.

Abstract: The present invention relates to a composite porous hollow-fiber membrane including a first layer and a second layer which each include a fluororesin-based polymer, in which at least a part of molecular chains of the fluororesin-based polymer is oriented in a longitudinal direction of the composite porous hollow-fiber membrane, the molecular chains of the fluororesin-based polymer have a degree of orientation it in the longitudinal direction of the composite porous hollow-fiber membrane of 0.4 or higher but less than 1.0, the degree of orientation it being calculated with the specific formula.

Abstract: A housing (30) of a hollow-fiber membrane module (101) is so configured as to have a small-diameter part (3B) having an inner diameter smaller than an inner diameter of a flow regulation cylinder (9) facing a part of the housing (30) on which a nozzle (8) is provided, and which is arranged on a lower side than a lower end of the flow regulation cylinder (9) in an axial direction of the hollow-fiber membrane module (101); or the flow regulation cylinder (9) is so configured as to have a small-diameter part (9G) which has an inner diameter smaller than the inner diameter of the flow regulation cylinder (9) facing the part of the housing (30) on which the nozzle (8) is provided, and which is arranged on a lower side than the existing region of the flow regulation holes (10) in the axial direction of the hollow-fiber membrane module (101).

Abstract: A hollow-fiber membrane module of the invention includes: a cylindrical case having a first end and a second end in a height direction thereof; a hollow-fiber membrane bundle being housed in the cylindrical case and having a plurality of hollow-fiber membranes each closed at an end part on the first end side and opened at an end part on the second end side; a first binding part binding the end parts on the first end side of the hollow-fiber membranes; a first flow channel guiding fluid to pass through the first binding part from the first end side to the second end side of the first binding part; and a channel material directing, at a terminal on the second end side of the first flow channel, a flow of at least a part of the fluid flowing out from the terminal on the second end side of the first flow channel toward a direction intersecting the height direction of the cylindrical case.

Abstract: The present invention relates to a composite porous hollow-fiber membrane including a first layer and a second layer which each include a fluororesin-based polymer, in which the first layer has a columnar texture oriented in a longitudinal direction of the composite porous hollow-fiber membrane, the columnar texture has an average value v of a Raman orientation parameter calculated with the specific formula, and the second layer has a three-dimensional network texture and has an average surface-pore diameter of 5.0 nm to 5.0 ?m.

Abstract: The present invention relates to a method for filtering a microbial culture solution using a membrane module, said method comprising four stages including (a) cross-flow filtration of the microbial culture solution, (b) rinsing with water, (c) washing with a chemical solution and (d) rinsing with water, wherein: the filtrate passing through the membrane module in the cross-flow filtration has a total sugar concentration of 1,000-100,000 mg/1 inclusive and a protein concentration of 50-1,000 mg/l inclusive; the aforesaid stage (c) comprises step (c-1) for washing with a chemical solution containing a hypochlorite and a nonionic surfactant; and the aforesaid stages (a) to (d) are repeated in this order.

Abstract: A cartridge type hollow fiber membrane module including a housing, a hollow-fiber membrane bundle having a plurality of hollow fiber membranes, a first potting part that bonds the hollow fiber membranes at at least one end of the bundle of the plurality of hollow fiber membranes such that the hollow fiber membranes are open, and a sealing material that fixes the first potting part to the housing liquid-tightly, wherein the first potting part comprises an inner potting part and an outer potting part, wherein the inner potting part and the outer potting part are both formed of a potting material, wherein the sealing material is in contact with the outer potting part, and wherein both the inner potting part and the outer potting part are formed in a sealing direction of the sealing material. The cartridge type hollow fiber membrane module is free of leakage and contamination due to separation of a potting material even when steam sterilization is performed.

Abstract: The present invention provides a hollow fiber membrane module that can effectively resolve the accumulation of suspended solids within the membrane module, lower running costs, and also operate stably. The present invention relates to a hollow fiber membrane molecule provided with: a cylindrical case having a first end and a second end in the direction of height; a plurality of hollow fiber membranes accommodated within the cylindrical case; and a first potting part accommodated within the cylindrical case and attaching the plurality of hollow fiber membranes together such that the end parts of the plurality of hollow membrane fibers at a first end side of the cylindrical case are open. The hollow fiber membranes are porous hollow fiber membranes having a breaking strength of 23 MPa, and the hollow membrane module has a membrane area per unit volume of 800-3700 m2/m3. The filling fraction for the hollow fiber membranes in a cross-section orthogonal to the direction of height of the cylindrical case is 25-38%.

Abstract: A cartridge type hollow-fiber membrane module of the present invention includes: a housing; a plurality of hollow fiber membranes housed in the housing; a first potting part which bundles first ends of the hollow fiber membranes while keeping the first ends open; a second potting part which bundles second ends of the hollow fiber membranes while keeping the second ends sealed; a fixing part which detachably fixes the first potting part to the housing; a sealing part which liquid-tightly seals a space between the first potting part and the housing; and a holding part which holds the second potting part so that the second potting part is detachable from the housing and so that liquids can pass through a space between the second potting part and the housing.

Abstract: A hollow-fiber membrane module of the invention includes: a cylindrical case having a first end and a second end in a height direction thereof; a hollow-fiber membrane bundle being housed in the cylindrical case and having a plurality of hollow-fiber membranes each closed at an end part on the first end side and opened at an end part on the second end side; a first binding part binding the end parts on the first end side of the hollow-fiber membranes; a first flow channel guiding fluid to pass through the first binding part from the first end side to the second end side of the first binding part; and a channel material directing, at a terminal on the second end side of the first flow channel, a flow of at least a part of the fluid flowing out from the terminal on the second end side of the first flow channel toward a direction intersecting the height direction of the cylindrical case.