Treatment of Food Industry Waste by Bench-Scale Upflow Anaerobic Sludge Blanket-Anoxic-Aerobic System

摘要

An upflow anaerobic sludge blanket (UASB)-anoxic-aerobic system was used for treatment of tomato and bean processing wastewater. At various hydraulic retention times, ranging from 0.7 to 5 days, excellent removal of chemical oxygen demand (COD), biochemical oxygen demand (BOD), total suspended solids (TSS), ammonia-nitrogen (NH_4-N), and total Kjeldahl nitrogen was achieved with final effluent BOD/TSS/NH_4-N concentrations of less than 15/15/1 mg/L. Biogas yield in the UASB reactor varied from 0.33 to 0.44 m~3/kgCOD_(re,pved). The kinetics of anaerobic treatment were investigated. The yield coefficient was 0.03 gVSS/gCOD; maximum specific growth rate was 0.24 day~(-1); Monod half velocity constant was 135 mgCOD/L; and specific substrate utilization rate was 3.25 gCOD/gVSS . d. Nitrification and denitrification kinetics were studied in batch experiments, and the rates were comparable with those in the continuous flow system.