Nitrate removal from sewage
Abstract
Abstract THERE IS DISCLOSED AN ACTIVATED SLUDGE SEWAGE TREATMENT PROCESS IN WHICH TEH NITROGEN CONTENT OF RAW SEWAGE SI REMOVED. IN THE PROCESS, RAW SEWAGE IS MIXED WITH ACTIVATED SLUDGE TO FORM A MIXED LIQUOR AND THE MIXED LIQUOR IS AERATED AT A RATE SUFFICIENT TO CONVERT AMMONIA PRESENT IN THE SEWAGE TO NITRATE. THE MIXED LIQUOR IS THEN PASSED TO A CONE WHEREIN IT IS MAINTAINED UNDER CONDITIONS IN WHICH THERE IS INSUFFICIENT OXYGEN PRESENT TO SATISFY THE NEEDS OF THE MICROORGANISMS IN THE MIXED LIQUOR. THIS CAUSES THE MICROORGANISMS TO BREAK DOWN THE NITRATE ND TO FULFILL THEIR OXYGEN NEEDS BY OBTAINING OXYGEN FROM THE NITRATE. NITROGEN GAS IS FORMED IN THE PROCESS AND IS EVOLVED FROM THE SYSTEM. THERE IS ALSO DISCLOSED A PROCESS WHEREBY THE PHOSPHATE CONTENT OF SEWAGE IS ALSO REDUCED. IN THIS EMBODIMENT CONDITIONS ARE CONTROLLED SO THAT THE SLUDGE WHICH IS WITHDRAWN FROM THE MIXED LIQUOR CONTAINS A SUBSTANTIAL PORTION OF THE PHOSPHATE CONTENT. THE FINAL EFFLUENT WHICH IS PASSED OUT OF THE SYSTEM IS SUBSTANTIALLY FREE OF PHOSPHATE AND NITRATE.
Inventors
- 👤 Gilbert V Levin
- 👤 George J Topol
Bibliographic Details
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| 3.5 Years (Year 4) | 1975-04-04 | 1975-10-04 | 1976-04-04 | $2000.00 | Window Closed / Lapsed |
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