Roles of SRT and HRT of an algal membrane bioreactor system with a tanks-in-series configuration for secondary wastewater effluent polishing

摘要: Abstract This study systematically determined the effect of uncoupling between solids retention time (SRT) and hydraulic (HRT) SRT/HRT ratio on algal growth nutrient (N P) removal in an membrane bioreactor (A-MBR) with a tanks-in-series configuration. Under 12-h light dark conditions intensity 150 μmol m −2  s −1 at mixed liquor surface, A-MBR system was operated fixed SRT (5 d) by varying HRT from 12 to 6 h, later (12 h) reducing 10 d 5 d. In synthetic secondary wastewater effluent treatment, highest efficiencies total N (TN, 73.4 ± 6.3%) P (TP, 91.3 ± 3.8%) were observed 10-d 24-h HRT, while productivity 131.7 g m −3  d (or 22.4 g m ) 5-d 6-h HRT. The biomass not coincident efficiency. For real polishing, 24 h applied based best performance earlier, resulting permeate containing 0.09 ± 0.05 mg/L TP 0.45 ± 0.08 mg/L TN, average 94.9 ± 3.6% 95.3 ± 0.9%, respectively. use increased about 45%. results demonstrate that control SRT, is important maximizing effluent.