Multi-pollutants (organic and inorganic) removal potential of scenedesmus species on municipal sewage water and analyzed their phycoremediation mechanisms

Abstract

Municipal sledge water is a combination of residential wastewater, industrial effluent, and precipitation water. The water quality parameters analyses results demonstrated that most of the parameters (pH: 5.6 ± 0.3, Turbidity: 102.31 ± 2.8 mg L−1, TH: 946.38 ± 3.7 mg L−1, BOD: 295.63 ± 5.4 mg L−1, COD: 482.41 ± 4.9 mg L−1, Ca: 278.74 ± 1.8 mg L−1, SO42−: 559.64 ± 11.4 mg L−1, Cd: 18.56 ± 1.37 mg L−1, Cr: 31.25 ± 1.49 mg L−1, Pb: 21.45 ± 1.12 mg L−1, and Zn: 48.65 ± 1.56 mg L−1) were considerably increased in quantities with slightly acidic in condition. The in-vitro phycoremediation study was carried out for two weeks with pre-identified Scenedesmus sp. Biomass in different groups of treatments (A, B, C, and D). Interestingly, most of the physicochemical parameters were significantly reduced in group C (4 × 103 cells mL−1) treated municipal sludge water in a shorter treatment period than in the other treatment groups. The phycoremediation percentage of group C were found as pH: 32.85%, EC: 52.81%, TDS: 31.32%, TH: 25.58%, BOD: 34.02%, COD: 26.47%, Ni: 58.94%, Ca: 44.75%, K: 42.74%, Mg: 39.52%, Na: 36.55%, Fe: 68%, Cl: 37.03%, SO42−: 16.77%, PO43−: 43.15%, F: 55.55%, Cd:44.88%, Cr:37.21%, Pb:43.8%, and Zn:33.17%. These findings suggest that increased biomass from Scenedesmus sp. can be used to significantly remediate municipal sludge water and that the obtained biomass and treated sludge can be used as feedstock's for bio fuel as well as bio fertilizer, respectively.