Avoidance of rising sludge in biological wastewater treatment clarifiers
Number of patents in Portfolio can not be more than 2000
United States of America Patent
Stats
-
Dec 3, 1985
Issued Date -
N/A
app pub date -
Dec 3, 1984
filing date -
Sep 29, 1983
priority date (Note) -
Expired
status (Latency Note)
Importance
Abstract
The problem of rising sludge in biological wastewater treatment secondary clarifiers is overcome by minimizing entrainment of nitrogen gas with mixed liquor entering the transfer pipe to the clarifier such that the level of dissolved nitrogen in the biomass settling in the clarifier remains less than that in equilibrium with nitrogen gas at the pressure prevailing in the biomass. This invention is most efficacious in cases where soluble oxides of nitrogen are present and are reduced by the biomass to elemental nitrogen. In accordance with one described embodiment the excess nitrogen is removed by degassing of the mixed liquor in the effluent pit of the system by deepening and widening the usual pit in such manner that the rate of descent of mixed liquor therein to a discharge outlet is less than 0.4 feet per second and the depth is greater than 4 feet, thus permitting the gas-containing macrobubbles to rise to the surface of the pit where these are degassed. The mixed liquor thus freed of macrobubbles is then passed through a hydraulic pressure zone enroute to the clarifier in which pressure zone the nuclei microbubbles are caused to dissolve.
First Claim
Family
International Classification(s)
Cited Art Landscape
Patent Citation Ranking
Recipient Email Address
Recipient Email Address
Comment
Recipient Email Address
Add to Portfolio(s)
To add this patent to one, or more, of your portfolios, simply click the add button.
This Patent is in these Portfolios:
Add to additional portfolios:
Last Refreshed On:
Changes done successfully