Abstract: A method for treating water including: passing water to be treated containing organic matters and ammonia nitrogen through a reaction tank containing a carrier for treatment under aerobic conditions, wherein a water content of the carrier is 50% or more and 96% or less; the carrier has continuous pores with a pore size of 30 ?m or less; an organic matter concentration in the water to be treated is 100 mg/L or less as a BOD5, and an ammonia nitrogen concentration is 50 mg/L or less; a retention time of the water to be treated in the reaction tank is 2 hours or less; and the organic matters and the ammonia nitrogen in the water to be treated are treated in the same tank.

Abstract: A process for treating wastewater including: feeding organic wastewater to a first aerobic tank and an anoxic tank; nitrifying and denitrifying the organic wastewater by bacteria supported on carriers in the first aerobic tank followed by discharging primary treated water; denitrifying the organic wastewater and the primary treated water by bacteria in an activated sludge in the anoxic tank followed by discharging secondary treated water; nitrifying the secondary treated water by bacteria in an activated sludge in the second aerobic tank followed by discharging tertiary treated water; and separating the sludge from the tertiary treated water in the solid-liquid separator followed by discharging final treated water while returning the sludge to the anoxic tank. According to this process, a load in a latter anoxic tank can be reduced, the anoxic tank can be downsized compared with the prior process and treated water with good water quality is stably provided.

Abstract: There is provided a shaped article made of porous hydrogel that contains a polyvinyl alcohol acetalized with a dialdehyde, wherein the shaped article after freeze-drying has a pore size of 0.1 to 50 ?m. Preferably, the shaped article made of porous hydrogel further contains a water-soluble polysaccharide. Also preferably, an acetalization degree of the polyvinyl alcohol is 1 to 50 mol %. Also preferably, the shaped article made of porous hydrogel is in the form of particles with a sphere-equivalent diameter of 1 to 20 mm. Such a shaped article made of porous hydrogel exhibits high strength and good survivability of microorganisms.

Abstract: There is provided a shaped article made of porous hydrogel that contains a polyvinyl alcohol acetalized with a dialdehyde, wherein the shaped article after freeze-drying has a pore size of 0.1 to 50 ?m. Preferably, the shaped article made of porous hydrogel further contains a water-soluble polysaccharide. Also preferably, an acetalization degree of the polyvinyl alcohol is 1 to 50 mol %. Also preferably, the shaped article made of porous hydrogel is in the form of particles with a sphere-equivalent diameter of 1 to 20 mm. Such a shaped article made of porous hydrogel exhibits high strength and good survivability of microorganisms.

Abstract: The aqueous dispersion of the present invention is produced by incorporating a block copolymer (II) into an aqueous dispersion (I) of a block copolymer (I) in an aqueous solution containing a basic compound. The block copolymer (I) is composed of a polymer block (A) mainly constituted by a constitutional unit derived from an olefin monomer and a polymer block (B) constituted by a constitutional unit derived from a vinyl monomer (b1) having a carboxyl group, a carboxylic anhydride group or a sulfonic group and a constitutional unit derived from another vinyl monomer (b2) copolymerizable with the vinyl monomer (b1). The content of the basic component is 0.05 equiv or more of the carboxyl group, carboxylic anhydride group or sulfonic group, each contained in the unit derived from the vinyl monomer (b1).

Abstract: The aqueous dispersion of the present invention is produced by incorporating a block copolymer (II) into an aqueous dispersion (I) of a block copolymer (I) in an aqueous solution containing a basic compound. The block copolymer (I) is composed of a polymer block (A) mainly constituted by a constitutional unit derived from an olefin monomer and a polymer block (B) constituted by a constitutional unit derived from a vinyl monomer (b1) having a carboxyl group, a carboxylic anhydride group or a sulfonic group and a constitutional unit derived from another vinyl monomer (b2) copolymerizable with the vinyl monomer (b1). The content of the basic component is 0.05 equiv or more of the carboxyl group, carboxylic anhydride group or sulfonic group, each contained in the unit derived from the vinyl monomer (b1).

Abstract: The invention provides an aqueous dispersion which includes i) an aqueous dispersion (I) resulting from dispersion of a block copolymer (I) composed of at least one polymer block (A) containing olefin monomer units and at least one polymer block (B) containing 2 to 100 mole percent of units derived from at least one vinyl monomer having a carboxyl or carboxylic anhydride group and 98 to 0 (zero) mole percent of units derived from another vinyl monomer or monomers copolymerizable with the carboxyl group- or carboxylic anhydride group-containing vinyl monomer, in an aqueous solution of not less than 0.05 equivalent, relative to the carboxyl or carboxylic anhydride group, of a basic substance, and ii) a polyurethane (II), iii) vinyl polymer (III) or iv) tackifier (IV) incorporated in the aqueous dispersion (I).

Abstract: The invention provides an aqueous dispersion which includes i) an aqueous dispersion (I) resulting from dispersion of a block copolymer (I) composed of at least one polymer block (A) containing olefin monomer units and at least one polymer block (B) containing 2 to 100 mole percent of units derived from at least one vinyl monomer having a carboxyl or carboxylic anhydride group and 98 to 0 (zero) mole percent of units derived from another vinyl monomer or monomers copolymerizable with the carboxyl group- or carboxylic anhydride group-containing vinyl monomer, in an aqueous solution of not less than 0.05 equivalent, relative to the carboxyl or carboxylic anhydride group, of a basic substance, and ii) a polyurethane (II), iii) vinyl polymer (III) or iv) tackifier (IV) incorporated in the aqueous dispersion (I).

Abstract: The invention provides an aqueous dispersion which includes i) an aqueous dispersion (I) resulting from dispersion of a block copolymer (I) composed of at least one polymer block (A) containing olefin monomer units and at least one polymer block (B) containing 2 to 100 mole percent of units derived from at least one vinyl monomer having a carboxyl or carboxylic anhydride group and 98 to 0 (zero) mole percent of units derived from another vinyl monomer or monomers copolymerizable with the carboxyl group- or carboxylic anhydride group-containing vinyl monomer, in an aqueous solution of not less than 0.05 equivalent, relative to the carboxyl or carboxylic anhydride group, of a basic substance, and ii) a polyurethane (II), iii) vinyl polymer (III) or iv) tackifier (IV) incorporated in the aqueous dispersion (I).

Abstract: The invention provides an aqueous dispersion which includes i) an aqueous dispersion (I) resulting from dispersion of a block copolymer (I) composed of at least one polymer block (A) containing olefin monomer units and at least one polymer block (B) containing 2 to 100 mole percent of units derived from at least one vinyl monomer having a carboxyl or carboxylic anhydride group and 98 to 0 (zero) mole percent of units derived from another vinyl monomer or monomers copolymerizable with the carboxyl group- or carboxylic anhydride group-containing vinyl monomer, in an aqueous solution of not less than 0.05 equivalent, relative to the carboxyl or carboxylic anhydride group, of a basic substance, and ii) a polyurethane (II), iii) vinyl polymer (III) or iv) tackifier (IV) incorporated in the aqueous dispersion (I).