Determination of The Optimal Adsorption Time in Adsorption-Biodegradation Anaerobic Sequencing Batch Reactor

The adsorption processes at different inflow of chemical oxygen demand (COD) were investigated, using an adsorption-biodegradation anaerobic sequencing batch reactor (AB-ASBR) operated at mesophilic temperature. Results indicated that COD removal by adsorption could reach to maximum value within 20 min, which related to the kind of substrates. With glucose as substrate, the maximum COD adsorption rates were 70%, 62% and 55% for different COD concentrations of 1000, 2000 and 3000 mg/L at 20 min, respectively. With milk powder as substrate, the maximum COD adsorption rates were 78%, 89%, 83%and 67% for different COD concentrations of 3000, 4000, 5000 and 7500 mg/L at 5 min, respectively. The produced volatile fatty acids (VFAs) concentration increased slowly. The produced biogas, mainly composed of CH₄, accounted for 72% in volume and had no obvious change.