Washing of precipitated sand in waste water treatment

Abstract

Abstract PURPOSE: Resource by washing precipitated sands and simultaneously simplification and sureness of a third treatment by passing second treated water through the precipitated sands after separating dusts and organic substances, filtering and washing the precipitated sands, or by back-washing them. CONSTITUTION: Dusts present in the precipitated sands in sewage are separated by mean of screens 1,6, and then organic substances are stripped by mean of a drum washer 7, etc. The precipitated sands are placed on the supporting bed 15 of a filter 14, and the precipitated sands are let to be a filter medium 16. The treated water which is subjected to a second treatment after separating the precipitated sands, is introduced in large quantities into the filter 14 over a long period of time. During filtration, floated substances are separated. The treated water is fed to a third treating water tank 19. If the inside pressure of filter 14 is elevated due to the presence of the floated substances, a blower 20 and a pump 21 are operated and back-washing is carried out by the third treated water. The precipitated sands are purified tore-use for aggregate, etc. and at the same time the third treatment is carried out simply and surely. COPYRIGHT: (C)1980,JPO&Japio

Inventors

• 👤 Takashi Nishimura
• 👤 Toshio Izuhara

Bibliographic Details