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Title: Performances of sewage treatment works discharging to an estuary : a marine environment or sensitive area : draft final report
Author: A. Dee
Author: B. Chambers
Author: J. Hobson
Author: A. Smith
Document Type: Monograph
Annotation: EA additional title info: performances of sewage treatment works discharging to an estuary : a marine environment or sensitive area : draft final report
This report presents the optimum performances of sewage treatment plant that can partially treat sewage discharging to an estuary or a coastal environment, or provide nutrient removal for discharges to bodies of water considered prone to eutrophication. The National Rivers Authority require such information on which to base consents. The main objectives were to derive indicators of optimum performance expressed as yearly means or 95 percentiles and to determine a single design loading appropriate to each process. Accordingly loadings and optimum performances are presented for suitable processes comprising of primary sedimentation tanks, activated sludge plant and oxidation ditches, conventional biological filtration plant, rotating biological contactors, tertiary nitrifying filters, sand filters and, chemical dosing plant to remove phosphorous. The performances have been determined by collating and evaluating the information, knowledge and experience available within WRc plc. Where possible the collected information has been validated against readily available data from UK sewage treatment works or in its absence from pilot tests performed at WRc over a period of one year in equipment exposed to the external environment. In the event of a lack of such data, information has been abstracted from the literature. Accordingly the validation data is variable since it has been derived from a number of different sources, and the loadings and optimum performances should only be used for guidance. Further works data should be collected, particularly for primary sedimentation tanks. In such cases, works should be visited to verify that the data represent periods when the works were in good operating order.
Publisher: National Rivers Authority
Publication Date: 1991
Publication Place: Marlow
Subject Keywords: Sewage treatmentEffluentsCoastal watersEstuariesDirectives (European Union)Water quality
Extent: 12; + appendices
Total file downloads: 295

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