Performance of Chlorella vulgaris in Phycoremediation of Livestock Effluent

Abstract

Livestock effluent is known to contain significantly higher concentrations of organic matter and challenging-to-degrade organic compounds compared to urban wastewater. This makes the effluent treatment challenging and adversely affects nearby aquatic environments if improperly treated. Phycoremediation uses microalgae in water and wastewater treatment. This research aim was to evaluate pollutant removal efficiencies, including chemical oxygen demand (COD), total suspended solids (TSS), nitrate (NO₃-N), turbidity, and phosphate (P), using microalgae Chlorella vulgaris (C. vulgaris) cultivation systems for livestock effluent treatment. The biomass weight of C. vulgaris in the cultivation systems was also observed. In this study, C. vulgaris was cultivated in closed cultivation systems in 5 L water bottles with different dilutions (100%, 75%, 50%, and 25%). The water effluent was compared to permissible values using the National Water Quality Standard (NWQS) class II for recreational water use. TSS was significantly removed by 61.97%, while COD and P were removed by 39.1% and 36.4%, respectively. The biomass growth was observed through the dry weight of the C.vulgaris. Therefore, the removal of nutrients from cattle farm effluent by phytoremediation using C. vulgaris demonstrates potential for treatment efficacy.