Treatment of sewage digester supernatant liquor
Abstract
Abstract PROCESS FOR REMOVAL OF 80 WEIGHT PERCENT OR MORE OF THE TOTAL PHOSPHORUS OF DIGESTER SUPERNATANT LIQUOR FROM THE CONVENTIONAL SEWAGE SLUDGE DIGESTION PROCESS COMPRISING HEATING THE DIGESTER SUPERNATANT LIQUOR FOR AT LEAST ABOUT 5 MINUTES AT A TEMPPERATURE IN THE RANGE OF FROM ABOUT 40* CENTIGRADE TO ABOUT 80* CENTIGRADE AT AMBIENT PRESSURE OR BELOW AMIBENT PRESSURE WHEN THE TEMPERATURE IS ABOUT 55* CENTIGRADE OR HIGHER AND IN THE RANGE OF FROM ABOUT 28 INCHES OF MERCURY (ABSOLUTE) OR BELOW WHEN THE TEMPERATURE IS BELOW ABOUT 55* CENTIGRADE; AND THEN SEPARTING PRECIPITED SOLIDS. THE PROCESS ALSO RESULTS IN SUBSTANTIAL REDUCTION OF TOTAL NITROGEN, CHEMICAL OXYGEN DEMAND AND BIOLOGICAL OXYGEN DEMAND OF THE DIGESTER SUPERNATANT LIQUOR.
Inventors
- 👤 Maria G Dunseth
- 👤 Joel J Brinkman
Bibliographic Details
Claims Analysis
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| 11.5 Years (Year 12) | 1983-01-10 | 1983-07-12 | 1984-01-11 | $7700.00 | Window Closed / Lapsed |