Analysis of an Outdoor Pilot-Scale Rotating Algae Biofilm Reactor for Power Optimization, Ash-Enhanced Productivity, And Nutrient Uptake

Outdoor testing of a rotating algae biofilm reactor (RABR) was performed to see how well it could remove nutrients from water and produce algae. By adjusting the operation settings, we found the lowest power needed to remove nitrogen and phosphorus. The lowest power values needed were 1.36 kWh per kilogram of nitrogen and 20.1 kWh per kilogram of phosphorus. The algae production rate reached a maximum of 7.09 grams per square meter per day. Detailed analysis showed that the reactor worked like a continuous flow system, and the performance was influenced by factors including light and temperature. The results also indicated that the algae absorbed more phosphorus than usual, which could be evidence of a phenomenon known as luxury phosphorus uptake. Additionally, a small amount (0.68%) of the biofilm's dry weight was made up of a compound called struvite.