Decentralised treatment of concentrated sewage at low temperature in a two-step anaerobic system : two upflow-hybrid septic tanks
The decentralised treatment of concentrated sewage (about 3,600 mgCOD/l) at low temperature was investigated in a two-step anaerobic system: two-anaerobic hybrid (AH) septic tanks (each 0.575 m3). The two reactors were placed in a temperature controlled-room and the HRT was 2.5 days for each reactor...
Veröffentlicht in: | Water science and technology : a journal of the International Association on Water Pollution Research. - 1986. - 48(2003), 6 vom: 15., Seite 219-26 |
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Format: | Aufsatz |
Sprache: | English |
Veröffentlicht: |
2003
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Zugriff auf das übergeordnete Werk: | Water science and technology : a journal of the International Association on Water Pollution Research |
Schlagworte: | Journal Article Research Support, Non-U.S. Gov't Sewage |
Zusammenfassung: | The decentralised treatment of concentrated sewage (about 3,600 mgCOD/l) at low temperature was investigated in a two-step anaerobic system: two-anaerobic hybrid (AH) septic tanks (each 0.575 m3). The two reactors were placed in a temperature controlled-room and the HRT was 2.5 days for each reactor. The system was fed with concentrated domestic sewage, mainly black water from about 40 toilets flushed with only 4 litre of water and a limited amount of grey water. The system showed high removal efficiency for the different COD fractions. Mean removal efficiencies in the two-step AH-septic tank at 5 days HRT and 13 degrees C were 94, 98, 74 and 78% for total COD, suspended COD, colloidal COD and dissolved COD respectively. The results of short run experiments indicated that the presence of reticulated polyurethane foam (RPF) media in the AH-septic tank improved the removal of suspended COD by 22%. The first AH-septic tank was full of sludge after 4 months of operation due to the high removal of particulate COD and the limited hydrolysis at low temperature conditions. Therefore, a simple mathematical model was developed based on ADM1 (the IWA model in 2002). Based on the experimental results and the mathematical model, only a one-step AH septic tank is required. An HRT of 5.5-7.5 days is needed for that one-step AH septic tank to treat concentrated sewage at a low temperature of 13 degrees C. Such a system can provide a total COD removal as high as 87% and will be full of sludge after a period of more than a year |
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Beschreibung: | Date Completed 13.04.2004 Date Revised 15.11.2006 published: Print Citation Status MEDLINE |
ISSN: | 0273-1223 |