Evaluation of the Performance of a Revolving Algae Biofilm System for Recovering Nitrogen and Phosphorus from Municipal Wastewater

An innovative algal biofilm technology is being pilot tested for potential application as a sustainable means for nitrogen (N) and phosphorus (P) recovery at Wastewater Resource Recovery Facilities (WRRFs). The technology uses revolving belts that extend vertically up from the wastewater to provide sunlight for microalgae growth. This Revolving Algae Biofilm (RAB) reactor has demonstrated the ability to recover nutrients in a smaller footprint than traditional raceway ponds. The resultant biomass is easily harvested from the biofilm with a scraping mechanism, providing an algae product that is ready to be processed for use as a biomass feedstock for bioplastics, fertilizers, biofuels, aquaculture feed, and other sustainable products. A pilot plant is in place at a major WRRF to test the performance of the RAB on a variety of wastewater streams. The results of a half year operation plus operating experiences are presented.