Bioremediation by Chlorella vulgaris: Potentials for Treatment of Municipal, Agricultural, and Industrial Wastewater Sources

Abstract

Developing countries such as the Philippines suffer from a lack of policy development and implementation on wastewater treatment and discharge. Chlorella vulgaris is a microscopic green algae that has been employed in other countries for WWT due to its ability to simultaneously reduce pollutants and produce valuable biomass. However, challenges in technology adaptation such as differential efficiency depending on the location and wastewater types were encountered. Three liquid wastes of different origins—municipal (public market), agricultural (piggery effluent), and industrial (meat processing plant) wastewaters, were used to gauge the remediation potentials of C. vulgaris in a simple photobioreactor setup. Treated samples from municipal, agricultural, and industrial wastewaters showed microalgal growth rates of 0.2685, 0.1527, and 0.1809, respectively, along the 6-day treatment period. Post-intervention comparisons of treated vs. untreated samples revealed a lower electrical conductivity, total dissolved solids, chemical oxygen demand, nutrients (nitrate, ammonia, phosphate), and fecal coliform (MPN/100 mL) on treated samples. Moreover, all treated samples demonstrated relatively higher dissolved oxygen concentrations, denoting the photosynthetic activity by the microalgae. Therefore, Chlorella vulgaris could be harnessed for the remediation of different wastewaters in Nagcarlan, Laguna, Philippines to circumvent issues in water reclamation and degradation.