Effects of temperature and hydraulic retention time on anaerobic sequencing batch reactor treatment of low-strength wastewater

• Published in: Water research (Oxford) 1997-10, Vol.31 (10), p.2455-2466
• Main Authors: Ndon, Udeme J., Dague, Richard R.
• Format: Article
• Language: English
• Subjects: anaerobic treatment; Applied sciences; ASBR; Biological and medical sciences; Biological treatment of waters; Biotechnology; Environment and pollution; Exact sciences and technology; Fundamental and applied biological sciences. Psychology; General purification processes; high-rate anaerobic process; HRTs; Industrial applications and implications. Economical aspects; low-strength wastewater; Pollution; various temperatures; Wastewaters; Water treatment and pollution
• ISSN: 0043-1354; 1879-2448
• DOI: 10.1016/S0043-1354(97)00105-X

Four laboratory-scale anaerobic sequencing batch reactors (ASBRs) were used to treat synthetic wastewaters at COD concentrations of 1000, 800, 600 and 400 mg/liter (BOD 5 of 490, 392, 294 and 196 mg/liter respectively). The ASBRs were operated at temperatures of 35, 25, 20 and 15°C. Reactor 1 was operated at a 48-h HRT, reactor 2 at 24-h HRT, reactor 3 at 16-h HRT and reactor 4 at a 12-h HRT. The four substrate concentrations were treated in each reactor and each temperature. Results of the study show 80–90% soluble COD removal efficiency at the various substrate concentrations, temperatures and HRTs, except during 15°C treatment of the more concentrated wastewater at the shorter HRTs. These findings show that the ASBR process could be used for the treatment of low-strength wastewaters at low temperatures, usually treated aerobically with high energy expenditures and large amounts of sludge production.