Patent · US Expired

Wastewater treatment process

US6585895B2 · kind B2 · utility

22Cited by
21References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 23, 2001
Grant dateJul 1, 2003
Priority date
Expiry dateApr 30, 2021

Classification

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

Abstract

There is provided a process for treating industrial wastewater that substantially eliminates the generation of excess solids in the system requiring mechanical removal. The wastewater undergoes an equalization step wherein hydraulic flow is smoothed and the pH of the wastewater is adjusted to near neutral pH conditions. The equalized wastewater is then transferred to aeration tanks where the organic process wastes are absorbed, metabolized, or otherwise biodegraded by the microorganisms in the mixed liquor in the aeration tanks. After the aeration step, the wastewater is separated by gravity in a clarifying step to separate the wastewater into a liquid phase and a semi-solid phase. The clarified liquid phase is withdrawn from the clarifier and discharged, while the semi-solid phase is transferred either directly back to the aeration/biological treatment step, as recycle-activated sludge, or into a bioreactor as waste-activated sludge. In the bioreactor the semi-solid phase is subjected to active aeration. The aerated waste-activated sludge is then batch-recycled to the equalization tank discharging to the aeration step where it is mixed into newly introduced untreated wastewater an…

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