Patent · US Expired

Two-stage anaerobic/aerobic treatment process

US4919815A · kind A · utility

117Cited by
23References
27Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 6, 1989
Grant dateApr 24, 1990
Priority date
Expiry dateFeb 6, 2009

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02W10/10
  • WIPO fieldEnvironmental technology
  • WIPO sectorChemistry

Abstract

A two-stage process for purifying wastewater includes the steps of biophysical anaerobic treatment to remove the majority of the COD, followed by biophysical aerobic treatment to further purify the wastewater. A powdered adsorbent, preferably powdered activated carbon, is used with biological solids in each treatment step. Excess biophysical solids from the aerobic step are transferred to the anaerobic step for digestion. Fresh powdered adsorbent is added to the aerobic treatment step to compensate for that transferred to the anaerobic treatment step. Solids concentration in the anaerobic step is controlled by wasting solids to disposal.

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