Characterization and modeling of nutrient-deficient tomato-processing wastewater treatment using an anaerobic/aerobic system

Tomato-processing wastewaters are typical of slowly biodegradable high strength wastewaters generated from the food canning industry. Three different samples of influent and three samples of anaerobic effluents corresponding to the three influents collected from an on-site pilot-scale anaerobic/aerobic system were characterized using respirometric methods. Respirometric studies demonstrated that the pretreatment in the anaerobic reactor of the pilot-scale system increased the readily biodegradable fraction from an average of 40% of the SCOD in the influent to 50% of the SCOD in the anaerobic effluent, improved kinetics from an average μmax of 1.5 d−1 in the influent to 3.5 d−1 in the anaerobic effluent, and eliminated nutrient deficiency. Furthermore, the system was calibrated and simulated by application of wastewater characterization and biokinetic data derived form respirometric tests of influent and anaerobic effluent in Activated Sludge Model no.1 (ASM1).