Bioremediation of Wastewater Using Microalgae

Abstract

This study describes the feasibility for treatment of waste waters in batch cultures by using selected strains of green microalgae Chlorella sp. A5. To investigate the role of algae in wastewater treatment algal samples were collected from polluted water. These samples were used to isolate most dominant and pollution tolerant algae and used for the treatment. The wastewater samples used in this study was prepared in laboratory synthetically having composition of Biological Oxygen Demand (BOD), Chemical Oxygen Demand (COD), Total Kjeldahl Nitrogen (TKN) and Total Phosphorus (TP) of 398, 705, 38 and 25 mg/L respectively further reduced by ~98.5%, 97.8%, 92.6% and 99.2% by the algal treatment respectively at the end of the process. The experiments were carried out in the laboratory of Food Technology and Biochemical Engg, Jadavpur University using synthetic medium. Chlorella sp. A5 was found to be the most dominant one. Synthetic Dairy Waste Water (SDWW) was prepared in such proportion that could mimic the original Dairy wastewater. Those isolated species of Chlorella was then added to the prepared SDWW. A control sample (C-SDWW--sample without the algal species) was also prepared. Both the SDWW and C-SDWW was analyzed periodically for the waste water quality parameters in an interval of 3 days to evaluate the performance of the algae. At the end of our experiment the nutrients and BOD, COD removal rate was found to be sufficiently high especially the phosphate removal.