Effects of Light Intensity on Algae Biofilms in Rotating Algae Biofilm Reactors (RABR)

There is a growing need for economically and ecologically friendly wastewater treatment processes. Utilizing natural algae biofilms to remediate excess nitrogen and phosphorus from municipal wastewater is a treatment technique of academic interest. Utilizing natural algae in rotating algae biofilm reactors (RABR) is a potential engineering application of algae biofilms for municipal wastewater anaerobic digestor effluent treatment. The ideal reactor operation would use sunlight as the light source for algae growth, however, there is little academic research on algae biofilm growth productivity across natural sunlight light intensity ranges. This research seeks to understand the relationship between rotating algae biofilm reactor algae surface area productivity, nitrogen removal, and phosphorus removal in connection with the amount of photosynthetic light available. The results of this study found that the greater amount of photosynthetically available radiation available to an algae biofilm caused increased biofilm productivity and nutrient (nitrogen and phosphorus) removal from the wastewater.