Patent · US Expired

Process for the clarification of liquids and suspensions

US6277285A · kind A · utility

26Cited by
9References
5Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMar 6, 2000
Grant dateAug 21, 2001
Priority date
Expiry dateMar 6, 2020

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC02F2305/12
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

Process employing the technique of ballasted flocculation with a step of injection, into the liquid to be clarified, of a ballast consisting of a granular material and of a polymer, followed by a flocculation step which leads to the formation of a ballasted floc, and by an accelerated settling step, said ballast being recirculated into the flocculation step, either as it is or after cleaning, wherein said process includes two recirculation regimes: PA1 a high-energy regime ensuring draw-off of the ballast contained in the ballasted floc, removal of the floc in the form of sludge and recycling of the cleaned ballast into the flocculation unit and, PA1 a low-energy regime ensuring transfer of the ballasted floc into the flocculation unit as long as the ballast ratio in the flocculator is greater than a predetermined level, this low-energy regime remaining in service while the high-energy regime is being put into action, but then being shut down during the operation of the high-energy regime, the two systems being employed alternately so as to maintain the ballast ratio at a predetermined level.

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