Efficacy of alginate immobilized microalgae in the bioremediation of shrimp aquaculture wastewater

Abstract

Bioremediation is a promising technology for eliminating pollutants from the atmosphere, replacing harmful substances, and preventing contamination. The current study’s primary objective was to see how effective marine microalgae organisms were at absorbing nutrients when cultured in aquaculture wastewater. Bioremediation trials were run with 18 immobilized microalgae at different RT (Reaction Time) of 75, 150, 225, and 300 min. The laboratory scale study demonstrated that microalgae such as Chlorella marina, Tetraselmis suecica and Picochlorum maculatum have the capabilities to remove maximum inorganic NH3-N and NO2-N. The maximum NO3-N reduction was observed in Chlorella marina (13.75–2.18 µmol/L). Reduction in PO43- was improved in Picochlorum maculatum with increasing RT and minimum concentrations of 10.86–2.39 µmol/L. Navicula sp. (20.17–3.11 µmol/L) and Nitzchia microcephala (20.17–4.46 µmol/L) utilized a higher concentration of silicate than other algal species from aquaculture effluents. Maximum Total Nitrogen (TN) and Total Phosphorus (TP) removal efficiency were observed for immobilized Chlorella marina at RT of 300 min. As a result, immobilized microalgae have been seen to be a viable substitute for nutrient remediation of aquaculture wastewater with RT ranging from 75 to 300 min.