Effect of organic carbon to nutrients (nitrogen and phosphorus) ratios on the performance of a novel microalgal-bacterial membrane photobioreactor

Abstract

This thesis aims to investigate the impact of Chemical Oxidation Demand (COD) to Nitrogen (N) ratio (COD/N) in influent on the biological and membrane performance of a novel Microalgal-Bacterial Membrane Photobioreactor (MB-MPBR). In the meantime, the influence of the COD/N ratio on biomass concentration, productivity and their influence on membrane fouling was studied using a well-controlled MB-MPBR receiving a synthetic medium-strength municipal wastewater containing glucose as a carbon source for a long term operational period (300 d). The COD/N ratio increases from 10.3:1, 13.9:1 and 16.8:1 throughout three phases of operation led to a remarkable amelioration in nutrients (N and Phosphorus (P)) removal, a COD removal was above 95% regardless of COD/N ratio, and the membrane performance also improved. The results suggested the capability of MB-MPBR for simultaneous removal of COD and nutrients in a single step. [...]