Chen H.-Y.Ng K.K.Lee C.-H.Chen T.-Y.Hong P.-K.A.Yang P.-Y.Lin C.-F.2019-05-212019-05-2120189608524https://www.scopus.com/inward/record.uri?eid=2-s2.0-85050521963&doi=10.1016%2fj.biortech.2018.07.091&partnerID=40&md5=3c419749e3488867ec155ec04d942797https://scholars.lib.ntu.edu.tw/handle/123456789/409483Anaerobic processes have been applied to treat low-strength domestic wastewaters with significant energy saving. However, anaerobic process effluents must be further removed of residual organics and total nitrogen before discharge. Reported here are an aerobic entrapped bio-technology (EBT) system and an EBT coupled with activated sludge (EBT + AS) system being tested as a post-anaerobic treatment. Both systems have been operated under aerobic condition to provide organics and total nitrogen removal, achieving COD removal by 74–88% and TN removal by 58–65% at hydraulic retention times of 8–24 h. ΔCOD/ΔNO3 ratios that represent the carbon usage efficiency as electron donors for denitrification were 1.82–1.93 in the EBT and 2.01–2.02 in the EBT + AS systems, with both ratios being lower (i.e. more efficient) than 6 typically required in traditional activated sludge bioreactors. Both systems demonstrate promise for polishing removal of COD and TN. © 2018 Elsevier LtdConcurrent nitrification and denitrification (CND); Delta COD to delta NO3; Entrapped bio-technology (EBT); Post-anaerobic treatment[SDGs]SDG6[SDGs]SDG7Denitrification; Energy conservation; Wastewater treatment; Activated sludge bioreactors; Anaerobic treatments; Delta COD to delta NO3; Domestic wastewater; Entrapped bio-technology (EBT); Hydraulic retention time; Nitrification and denitrification; Total nitrogen removal; Nitrogen removal; carbon; nitrate; nitrogen; organic compound; nitrogen; activated sludge; anoxic conditions; biomass; bioreactor; biotechnology; chemical oxygen demand; denitrification; effluent; nitrification; nitrogen; oxic conditions; pollutant removal; activated sludge; Article; biomass; biotechnology; chemical oxygen demand; denitrification; effluent; electron; entrapped biotechology; priority journal; retention time; waste water management; biomass; bioreactor; denitrification; sewage; Biomass; Bioreactors; Denitrification; Nitrogen; Sewage; Waste Disposal, Fluidjournal article10.1016/j.biortech.2018.07.091300599442-s2.0-85050521963