Abstract: A system for the degradation treatment of organics in organically-polluted water is provided with a treatment tank for receiving, as the organically-polluted water, sewage or wastewater from a food-related factory. The treatment tank includes an inlet, an outlet arranged at a position upper than a vertical position of the inlet, and at least one, preferably plural air diffuser pipes for intermittently feeding oxygen-containing gas into the organically-polluted water in the treatment tank. The air diffuser pipe(s) are arranged at a position lower than the vertical position of the inlet such that an aerobic zone and an anaerobic zone can be formed in an upper part and a lower part of the treatment tank to effect degradation of soluble organics in the organically-polluted water primarily with aerobic bacteria and to effect degradation of solid organics in the organically-polluted water primarily with anaerobic bacteria, respectively.

Abstract: A system for the degradation treatment of organics in organically-polluted water is provided with a treatment tank for receiving, as the organically-polluted water, sewage or wastewater from a food-related factory. The treatment tank includes an inlet, an outlet arranged at a position upper than a vertical position of the inlet, and at least one, preferably plural air diffuser pipes for intermittently feeding oxygen-containing gas into the organically-polluted water in the treatment tank.

Abstract: A device for collecting water polluting phytoplankton drifts and a method for collecting water polluting phytoplankton drifts by use of such device is provided such that the deterioration of water quality as a result of extraordinary proliferation of phytoplankton is suppressed and prevented such that a water area is kept clean. The device 1 for collecting water polluting phytoplankton drifts defines a predetermined volume of space therewithin with enclosing faces, the enclosing faces including at least one face section 3 composed of a water blocking member and other face sections 4 and 5 composed of a plurality of water admitting members, each water admitting member being formed with a plurality of water admitting holes.

Abstract: In a polluted water purifying method and apparatus, a purification treatment tank is filled with massive purifying members in a purifying region, each massive purifying member including plural opening portions having an equivalent diameter of 1 to 5 cm which are provided on the surface thereof, and plural interconnecting channels which intercommunicate with one another and provided inside of the members, and each opening portions continuously intercommunicating with at least one of the channels. Polluted water containing SS, BOD, etc. is supplied through the purifying region of the tank to be brought into contact with the massive purifying members.

Abstract: In a solid material flow-separating method for separating fine solid material from fluid, plural massive, net-shaped or pipe-shaped flow-separating members each having opening portions of about 1 to 5 cm in equivalent diameter are disposed along a fluid flowing direction in a treatment tank, and the fine solid material floating in the fluid is trapped and collected through the opening portions, and help up in a predetermined area, thereby separating the fine solid material from the fluid.