IMPROVING THE EFFLUENT OF SMALL WASTEWATER TREATMENT PLANTS BY BACTERIA REDUCTION AND NUTRIENT REMOVAL WITH AN ALGAL BIOFILM

Investigation at two experimental domestic wastewater treatment plants in Hamburg showing the possibility of polishing the effluent with the aid of an attached algal biofilm as a tertiary stage. A high potential for bacterial reduction is thus obtained and the problem of separation of algae and water can also be avoided. Additionally, algae reduced nitrogen and phosphorus concentrations by forming biomass. The process can be simply implemented and operated with solar energy.