Patent · US Expired

Methods and apparatus for treating wastewater

US3933640A · kind A · utility

17Cited by
11References
13Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 20, 1974
Grant dateJan 20, 1976
Priority date
Expiry dateSep 20, 1994

Classification

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

Abstract

Methods and apparatus for treating wastewater, such as municipal sewage, are provided in which an oxygen enriched feed gas is supplied to an oxygenation chamber wherein oxygen is efficiently dissolved in wastewater (mixed liquor) by means of a static mixing device. The chamber is preferably submerged in a large body of wastewater being treated, such as is commonly found in the secondary stage of an activated sludge wastewater treatment system with the chamber being adapted to receive such wastewater from a location slightly below the surface thereof. Oxygenated wastewater is discharged from the chamber in either a radial or multi-directional pattern at a sufficient velocity to effect a thorough mixing of the oxygenated wastewater and the large body of wastewater contained in the secondary stage treatment tank. The overall concentration of dissolved oxygen in the wastewater is maintained throughout the tank to a level sufficient to sustain microbial digestion of organic waste while providing the requisite stirring necessary to preclude settling of solids from the wastewater.

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