Polymer membrane for water treatment and method for manufacture of same, and water treatment method

Abstract

A polymer membrane for water treatment, characterized in comprising a hollow fiber membrane having a self-supporting design composed of the substantially single principal structural material, with an outer diameter of 3.6 mm to 10 mm and a ratio of outer diameter to thickness, SDR, of 3.6 to 34.

1 - 15 . (canceled) 
     
     
         16 . A polymer membrane for water treatment comprising
 a hollow fiber membrane having a self-supporting design composed of vinyl chloride resin as a substantially single principal structural material,   with an outer diameter of 3.6 mm to 10 mm and   a ratio of outer diameter to thickness, SDR, of 5.8 to 34.   
     
     
         17 . The polymer membrane for water treatment according to  claim 16 , wherein in the cross-section in the radial direction of the hollow fiber membrane;
 (a) the porosity based on the hollow fiber membrane cross-sectional area is 30-85%,   (b) the pores with a short axis dimension of 10-100 μm are 80% or more of the total pore surface area, and   (c) there is a laminar distribution of pores constituting the innermost layer, inner layer, outer layer and outermost layer from the center in the radial direction, and the long axis dimension of the pores in each of the inner layer and outer layer comprises 20-50% of the thickness, respectively, while the long axis dimension of the pores in each of the innermost layer and outermost layer comprises 0-20% of the thickness, respectively.   
     
     
         18 . The polymer membrane for water treatment according to  claim 16 , wherein the polymer membrane has the fractionation property of an ultrafiltration membrane or a microfiltration membrane. 
     
     
         19 . The polymer membrane for water treatment according to  claim 17 , wherein the polymer membrane has the fractionation property of an ultrafiltration membrane or a microfiltration membrane. 
     
     
         20 . The polymer membrane for water treatment according to  claim 16 , wherein the polymer membrane has;
 an internal pressure resistance of 0.3 MPa or greater,   an external pressure resistance of 0.1 MPa or greater, and   pure water flux of 100 L/m 2 ·hr·atm or greater.   
     
     
         21 . The polymer membrane for water treatment according to  claim 16 , wherein the main structural material is poly(vinyl chloride), chlorinated poly(vinyl chloride), or a vinyl chloride-chlorinated vinyl chloride copolymer. 
     
     
         22 . The polymer membrane for water treatment according to  claim 16 , wherein the degree of polymerization of the vinyl chloride resin is 250-3000. 
     
     
         23 . The polymer membrane for water treatment according to  claim 16 , wherein the chlorine content in the vinyl chloride resin is 56.7 to 73.2%. 
     
     
         24 . The polymer membrane for water treatment according to  claim 16 , wherein the mass ratio of vinyl chloride monomer units in the vinyl chloride resin amounts to 50-99 mass %. 
     
     
         25 . A method for the manufacture of a polymer membrane for water treatment comprising;
 preparing a resin solution from vinyl chloride resin as a substantially single principal structural material, and   coagulating the resin solution by discharging from a discharge port into a coagulation tank at within ±30° of horizontal with respect to the ground,   the polymer membrane is   a hollow fiber membrane having a self-supporting design composed of vinyl chloride resin as a substantially single principal structural material,   with an outer diameter of 3.6 mm to 10 mm and   a ratio of outer diameter to thickness, SDR, of 5.8 to 34.   
     
     
         26 . The method for the manufacture of a polymer membrane for water treatment according to  claim 25  comprising;
 coagulating the resin solution by discharging from a discharge port in which a discharge direction of the resin solution is in a horizontal direction with respect to the ground into a coagulation tank. 
 
     
     
         27 . The method for the manufacture of a polymer membrane for water treatment according to  claim 25  that uses a spinneret provided with a discharge port, where the discharge port discharges the resin solution in an immersed state into a coagulation tank that contains a non-solvent. 
     
     
         28 . The method for the manufacture of a polymer membrane for water treatment according to  claim 26  that uses a spinneret provided with a discharge port, where the discharge port discharges the resin solution in an immersed state into a coagulation tank that contains a non-solvent. 
     
     
         29 . The method for the manufacture of a polymer membrane for water treatment according to  claim 25 , which further comprises;
 cutting the membrane obtained within the tank, or   cutting the membrane outside the tank at a position higher than the discharge port.   
     
     
         30 . The method for the manufacture of a polymer membrane for water treatment according to  claim 25 , wherein the difference in specific gravity between the resin solution and the non-solvent is within 1.0. 
     
     
         31 . A method for water treatment characterized in that the polymer membrane for water treatment according to  claim 16  is used as a separation membrane. 
     
     
         32 . A method for water treatment characterized in separating water by passing microbiological treated wastewater using activated sludge inside the polymer membrane for water treatment according to  claim 16 . 
     
     
         33 . The method for the manufacture of a polymer membrane for water treatment according to  claim 25 ,
 using a spinneret provided with a discharge port,   after preparing the resin solution,   submerging the spinneret into a coagulation tank while discharging the resin solution previously from the spinneret in the air, and   discharging the resin solution into a coagulation tank.   
     
     
         34 . A method for the manufacture of a polymer membrane for water treatment comprising;
 preparing a resin solution from a substantially single principal structural material,   using a spinneret provided with a discharge port,   after preparing the resin solution,   submerging the spinneret into a coagulation tank while discharging the resin solution previously from the spinneret in the air, and   coagulating the resin solution by discharging from a discharge port into a coagulation tank at within ±30° of horizontal with respect to the ground,   the polymer membrane is   a hollow fiber membrane having a self-supporting design composed of the substantially single principal structural material,   with an outer diameter of 3.6 mm to 10 mm and   a ratio of outer diameter to thickness, SDR, of 5.8 to 34.