Use of microalgae in wastewater treatment to remove contaminants and purify biogas
This thesis presents laboratory-scale experiments that explore the potential use of microalgae in wastewater treatment. As tertiary treatment, microalgae strains grown in secondary effluent from a municipal wastewater treatment plant successfully removed nutrients (nitrogen and phosphorous) and heavy metals (copper and zinc). Nitrogen in the form of ammonia was removed with up to 94.6% removal, and total phosphorous removal reached up to 95.8% removal. Copper and zinc removal rates reached up to 84.4% and 96.3%. Simulated biogas was exposed to microalgae grown in secondary effluent to observe CO2 uptake. Complete CO2 removal was achieved. The use of microalgae to treat secondary effluent while purifying raw biogas from anaerobic digesters represents a more sustainable approach to wastewater treatment than current practices.