Utilizing algal oxygen production for advanced wastewater treatment in a Moving Bed Biofilm Reactor (MBBR) – the Biologically Aerated Reactor (BAR

A novel wastewater treatment system has been developed, utilizing an oxygen-rich algal liquid to supply oxygen to an aerobic biofilm reactor. Aerobic treatment of wastewater takes place in a Moving Bed Biofilm Reactor, where the aerobic biomass which breaks down organic and nitrogenous pollutants grows as a biofilm on floating carriers. Algae grown in an open raceway pond produce oxygen through photosynthesis, and are recirculated through the MBBR in order to supply oxygen to the aerobic process taking place on the biofilm. The system has been piloted for 18 months within a municipal WWTP, producing a high quality effluent with no aeration costs, and a fraction of the total energy consumption of conventional processes. The sizing of the required algal raceways and recirculation rate to the MBBR were determined, and the relative functions of the algal raceway and the MBBR were determined by oxygen uptake rate testing of the different components of the system.