Evaluation of Bioaugmentation to Improve Wastewater Treatment

Bioaugmentation can enhance the removal of hazardous wastes or improve nutrient removal in activated sludge processes. Bioaugmentation processes can be classified into several major approaches, such as adding enriched cultures from commercial “off-site” sources; adding cells produced from other treatment plants or “on-site” reactors, or growing additional biomass with the return activated sludge. This paper quantifies the effectiveness of bioaugmentation processes based on experimental results and verified models. In the first part of the paper we present our lab-scale experiments and simulations with bioaugmentation to enhance the removal of an aromatic compound. Based upon a similar model, the second part of this paper compares different on-site bioaugmentation approaches to improve nitrogen removal. The results suggested that using enricher reactor with return sludge would likely be more useful at lower temperature and required less reactor volume while the enricher-reactor approach would likely be more advantageous in the presence of inhibitory compound(s).