Liquid purification or separation – Processes – Treatment by living organism
Patent
1989-07-21
1990-09-11
Wyse, Tom
Liquid purification or separation
Processes
Treatment by living organism
210630, 210631, 210906, C02F 330
Patent
active
049560948
ABSTRACT:
There is disclosed an activated sludge wastewater treatment process which comprises aerating a mixed liquor comprising phosphate-containing influent wastewater and activated sludge in an aeration or high-purity oxygen zone to reduce the BOD/COD content of the wastewater and to cause the microorganisms present to take up phosphate. A phosphate-enriched sludge in which the phosphorus is present primarily in the sludge solids is separated from the mixed liquor to provide a substantially phosphate-free effluent. At least a portion of said phosphate-enriched sludge is passed to a phosphate pre-stripping zone, either in a separate tank or within the phosphate stripper tank itself, where BOD/COD-containing water, or feedwater, containing at least 50 mg/L of BOD, is added to poise the sludge organisms to begin enhanced rapid release of dissolved phosphate by pre-stripping it from the sludge or poising the sludge for rapid, enhanced release of phosphate. Then, the sludge is passed to a phosphate stripping zone. In the phosphate stripping zone, the sludge settles to form a supernatant liquor in the stripping zone upper section and settled sludge in the stripping zone lower section. The settled sludge is maintained under anaerobic conditions for a time sufficient to complete the release of the desired amount of phosphate from the sludge solids to the liquid phase of said settled sludge. At least a portion of the anaerobic sludge from the phosphate stripping zone is recycled to the aeration or high-purity oxygen zone as activatd sludge. The phosphate-rich supernatant from the phosphate stripping zone may be applied directly to land, or treated with a chemical precipitating agent to precipitate the phosphate therefrom and the precipitated phosphate may then be removed through the use of a reactor/clarifier, primary or secondary clarifier or other tankage, thus preparing the phosphate for final disposal directly or as fresh, digested or otherwise treated sludge.
REFERENCES:
patent: 4042493 (1977-08-01), Matsch et al.
patent: 4141822 (1979-02-01), Levin et al.
patent: 4183808 (1980-01-01), Ornevich
patent: 4460470 (1984-07-01), Reimann
patent: 4488968 (1984-12-01), Hong et al.
"Applying Biotechnology to Clean Up Pollution", Nell Henderson, The Washington Post, Apr. 28, 1986.
"A Parametric Model for Biological Excess Phosphorus Removal", I.A.W.P.R Post Conference Seminar on Phosphate Removal, Pretoria, South Africa, 1982, Siebritz et al.
"The Effect of Aeration Basin Configuration on Activated Sludge Bulking at Low Organic Loading", Water Science and Technology, 14, 407-427, S-E. Lee et al., Capetown, 1982.
Levin Gilbert V.
Wright Ronald R.
Biospherics Incorporated
Wyse Tom
LandOfFree
Enhanced phosphate removal from bod-containing wastewater does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Enhanced phosphate removal from bod-containing wastewater, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Enhanced phosphate removal from bod-containing wastewater will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1183128