Patent · US Expired

Activated-sludge process for wastewater treatment

US4500427A · kind A · utility

5Cited by
5References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 5, 1982
Grant dateFeb 19, 1985
Priority date
Expiry dateNov 5, 2002

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S210/903
  • WIPO fieldEnvironmental technology
  • WIPO sectorChemistry

Abstract

An activated-sludge process for wastewater treatment comprising the steps of: PA1 (1) feeding raw wastewater to an aeration tank containing activated sludge; PA1 (2) supplying air into the aeration tank to produce aerobic and anaerobic areas in said tank; PA1 (3) separating sludge from the mixed liquor coming out of the aeration tank and concentrating at least part of the separated sludge or said mixed liquor in a concentrator to thereby produce concentrated sludge and separated water; and PA1 (4) feeding the concentrated sludge into the aeration tank and maintaining the MLSS concentration in said tank at a value between 7,000 to 15,000 mg/liter, thereby removing the organic matter and nitrogen components from the wastewater within said aeration tank.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.