The purpose of this study was to develop a new configuration for a compact on-site treatment system, which could become an attractive alternative, from technical, economic, social and environmental viewpoints, to the technologies that are currently employed. The treatment unit consists of a cylindrical tank, where half of the volume is used as a modified septic tank and the other half is divided between an anaerobic hybrid reactor and a trickling filter. An intermittent feeding system was used, with minimum, mean and maximum flowrate settings (Qmin = 0.25l.s(-1), Qmean = 0.50l.s(-1) and Qmax = 1.00l.s(-1)), to reflect the actual operating conditions of a compact on-site treatment system serving a typical dwelling. An average 24-hour hydraulic detention time was used, corresponding to a flowrate of 750l.d(-1). High removal efficiencies and low concentrations of COD, BOD and TSS in the final effluent were achieved, even when the unit was exposed to hydraulic loading peaks during feeding periods at maximum flowrate.
[1]
Sonia Maria Manso Vieira,et al.
Discussion Report on Reactor Design of Anaerobic Filters and Sludge Bed Reactors
,
1991
.
[2]
Grietje Zeeman,et al.
Anaerobic sewage treatment
,
2005
.
[3]
G Lettinga,et al.
Decentralised treatment of concentrated sewage at low temperature in a two-step anaerobic system: two upflow-hybrid septic tanks.
,
2003,
Water science and technology : a journal of the International Association on Water Pollution Research.
[4]
G. Zeeman,et al.
Low temperature pre-treatment of domestic sewage in an anaerobic hybrid or an anaerobic filter reactor.
,
2002,
Bioresource technology.
[5]
Gatze Lettinga,et al.
Anaerobic Treatment of Domestic Wastewater in Small Scale UASB Reactors
,
1992
.