CONTACT FILTER AND WASTEWATER PURIFICATION APPARATUS FOR BIOLOGICAL CONTACT AERATION-TYPE WATER TREATMENT EQUIPMENT

摘要

PURPOSE:To improve wastewater treatment efficiency by foaming a synthetic plastics so as to form numberless holes and small projects on the surface of lattices and installing a contact filter comprised of the lattices in a purifying tub. CONSTITUTION:In molding process of a lattice molded body 1 using a synthetic plastics such as polyethylene, a foaming agent is added to the plastics so as to form numberless holes 11 and projects 12 by the foaming gas, and a contact filter (a) is prepared from the foamed lattice molded body 1 and the filter is installed in a purifying tub 2. A biological film adheres to the lattices 10 of the lattice molded body 1 quickly and the lattice molded body has high adhesion strength and retaining power to the biological film and thus purifying efficiency becomes high due to a large amount of adhering biological film. Weight per unit volume of the filter is decreased, resulting in easiness of transporting and handling.