Toray Industries, Inc.

Chiyoda Corporation

Chiyoda Chemical Engineering Construction Co., Ltd.

Hiromi Satoh

Jun Hasegawa

Masahide Taniguchi

Atsushi Kitanaka

Yoshinori Yushina

Kazuhige Kawamura

Toshinobu Imahama

Masayo Shinohara

A method of treating wastewater containing an organic compound includes feeding wastewater to an anoxic tank, adding compounds containing nitrogen and phosphorus components to wastewater, performing anaerobic treatment on wastewater, and discharging treated wastewater as pre-treated water; introducing pre-treated water into an anaerobic treatment tank, performing anaerobic treatment on pre-treated water, thereby decomposing the organic compound into organic compounds of smaller molecular size and a mixture gas containing methane and carbon dioxide, and discharging treated water as primary water; introducing primary water into an aerobic treatment tank, performing aerobic treatment on primary water, and discharging treated water through a solid-liquid separator as secondary water; and introducing at least a part of secondary water into a reverse osmosis membrane separation unit, and separating part of secondary water into RO permeated water and RO concentrated brine, wherein at least a part of RO concentrated brine is recycled to the anoxic tank.

Method of treating a plant wastewater and treatment system therefor

A cylindrical hollow carrier for microorganisms is prepared by subjecting a nonwoven fabric having a specific gravity of not greater than 1.0 to a surface smoothing treatment at an elevated temperature of 200.degree. to 450.degree. C., then pressing with a roller to give the nonwoven fabric a thickness of 1 to 5 mm and a weight per unit area of 30 to 300 mg/cm.sup.2 and then forming the nonwoven fabrics into a cylindrical hollow shape. The carrier has a compression weight of not less than 400 g, and preferably an outer diameter of about 25 to 100 mm and a length of about 40 to 60 mm. The nonwoven fabric may be formed of 35 to 90% fibers of 50 to 600 denier and 10 to 65% fibers of 20 to 1 denier.

Cylindrical hollow carriers for microorganisms made of nonwoven fabric

Growing community of inventors

Yokohama, Japan

Hiromi Satoh