IMPACT OF CONFIGURATIONAL DIFFERENCES AND CHEMICAL PERTURBATIONS ON THE NUTRIENT REMOVAL PERFORMANCE AND MICROBIOME OF AIR-SCOURING AND RECIPROCATION MODIFIED LUDZACK-ETTINGER MEMBRANE BIOREACTORS

Abstract

Activated sludge process coupled with membrane technology has gained popularity for domestic wastewater treatment use due to its ability to produce high quality effluent with low environmental footprint. With continuous filtration, membranes become prone to biofouling which may lead to a decrease in water quality and membrane damage. In this dissertation, two modified Ludzack-Ettinger membrane bioreactors (MLE-MBRs) employing different anti-fouling mechanisms were used to evaluate nutrient removal performance and changes in microbial community composition in the presence of antimicrobial compounds. The overall dissolved oxygen concentration in the systems played a major role in the removal of nitrogen and phosphorus from the wastewater. Meanwhile, continuous addition of antibiotics at environmentally-relevant concentrations in the MLE-MBRs showed significant reduction in the oxidation of ammonia as well as effects in the relative abundances of nutrient-removing organisms. These effects prove that the presence of antimicrobials in wastewater treatment plants could significantly impact biological nutrient removal.