Patent · US Expired

Liquid treatment method and apparatus

US5156742A · kind A · utility

30Cited by
8References
19Claims
0Family size

Assignee

Inventor

Key dates

Filing dateFeb 25, 1992
Grant dateOct 20, 1992
Priority date
Expiry dateFeb 25, 2012

Classification

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

Abstract

An improved method and apparatus for treating liquor containing biodegradable wastes wherein the liquor is first delivered to a quiescent primary settling zone and then to an aeration zone. The aerated liquor is delivered downwardly through a column of submerged fixed media having a high surface area to volume ratio so that aerobic microorganisms can grow on their surface. The liquor is recirculated through the aeration zone and fixed media, and is withdrawn from the unit after treatment. A portion of the aerated liquor from the top of the fixed media is recycled back into the primary settling zone to denitrify the nitrate rich aerated liquor by deoxygenating the dissolved nitrates and to equalize the BOD load in the secondary aerobic treatment zone.

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