Community onsite treatment of cold strong sewage in a UASB-septic tank.
Two community onsite UASB-septic tanks namely R1 and R2 were operated under two different HRT (2 days for R1 and 4 days for R2) in parallel over a year and monitored over the cold half of the year. During the monitoring period, the sewage was characterised by a high COD(tot) of 905mg/l with a high fraction of COD(ss), viz. about 43.7%, and rather low temperature of 17.3 degrees C. The achieved removal efficiencies in R1 and R2 for COD(tot), COD(sus), COD(col), COD(dis), BOD(5) and TSS were "51%, 83%, 20%, 24%, 45% and 74%" and "54%, 87%, 10%, 28%, 49% and 78%", respectively. The difference in the removal efficiencies of those parameters in R1 and R2 is marginal and was only significant (p<0.05) for COD(sus). The sludge filling period of the reactors is expected to be 4-7 years. In view of that, the UASB-septic tank system is a robust and compact system as it can be adequately designed in Palestine at 2 days HRT.
Al-Jamal
Wafa
W
Institute of Environmental and Water Studies, Birzeit University, Birzeit, The West Bank, Palestine.
Mahmoud
Nidal
N
D019149:Bioreactors / Q000382:microbiology*; D002947:Cities; D003080:Cold Temperature; D004867:Equipment Design; D019544:Equipment Failure Analysis; D009930:Organic Chemicals / Q000302:isolation & purification / Q000378:metabolism*; D012037:Refuse Disposal / Q000295:instrumentation* / Q000379:methods; D012722:Sewage / Q000382:microbiology*; D014874:Water Pollutants, Chemical / Q000302:isolation & purification / Q000378:metabolism*; D018508:Water Purification / Q000295:instrumentation*
D009930:Organic Chemicals; D012722:Sewage; D014874:Water Pollutants, Chemical