title: Energy savings and higher volumetric loading rate achieved in the conventional anoxic-oxic process for sewage treatment by enhancing biomass retention in the secondary clarifier.
abstract: This is the first study to achieve a short HRT (∼2h for the A/O reactor), high MLSS (∼10gL-1), and high volumetric loading (∼3.7kg CODm-3d-1and ∼0.6kg NH4-Nm-3d-1) in the A/O process for sewage treatment by enhancing biomass retention in the secondary clarifier (∼4h settling time), which we refer to as the high-performance A/O process (HP-A/O) in this paper. Over 258days of continuous operation, with a decrease in HRT from 12 to 2h, remarkable COD (95±3%), NH4+-N (98±2%), TN (79±5%), and TP (74±10%) removals were stably achieved, while the air requirement significantly decreased by 22%. The HP-A/O process offers advantages over the conventional A/O process (6-8h for A/O reactor, 3-5gL-1MLSS, and ∼1.0kg CODm-3d-1) for sewage treatment in terms of its lower energy consumption, smaller footprint and reactor requirements.
authors.affiliation: School of Environment, MOE Key Laboratory of Water and Sediment Sciences/State Key Lab of Water Environment Simulation, Beijing Normal University, Beijing 100875, China.
authors.forename: Xueyu
authors.initials: X
authors.lastname: Zhang
authors.affiliation: School of Environment, MOE Key Laboratory of Water and Sediment Sciences/State Key Lab of Water Environment Simulation, Beijing Normal University, Beijing 100875, China.
authors.forename: Fengyuan
authors.initials: F
authors.lastname: Liu
authors.affiliation: School of Environment, MOE Key Laboratory of Water and Sediment Sciences/State Key Lab of Water Environment Simulation, Beijing Normal University, Beijing 100875, China. Electronic address: zsk@bnu.edu.cn.
authors.forename: Shaokui
authors.initials: S
authors.lastname: Zheng
mesh_terms: D018533:Biomass; D019149:Bioreactors; D012722:Sewage; D014865:Waste Disposal, Fluid
chemical_list: D012722:Sewage
keywords: A/O process; Biomass retention; Energy saving; Secondary clarifier; Settling time; Sewage treatment