Evaluation of Contaminant Removal from Domestic Wastewater Using Microalgae Cultivated in Photobioreactors (PBR) Supplied with CO₂ and Compressed Air (#1274)

Authors

Monzón Martínez, Lalo José

Abstract

This study aimed to evaluate the removal of contaminants (COD, nitrogen, and phosphorus) through the use of microalgae cultivated in photobioreactors (PBR). The research was conducted using four pilot-scale PBRs inoculated with a microalgal concentrate (Scenedesmus almeriensis) at a concentration of 1 g/L. The PBRs were supplied with CO₂ and compressed air to determine whether CO₂ influences microalgal growth by enhancing nutrient assimilation. The quality of domestic wastewater was assessed through parameters such as pH, temperature, total suspended solids (TSS), chemical oxygen demand (COD), total organic carbon (TOC), total nitrogen, and total phosphorus. The experimental setup for the four PBRs was as follows: PBR 1: 100% wastewater, microalgal inoculum, compressed air, and CO₂; PBR 2: 70% wastewater, 30% dilution water, microalgal inoculum, compressed air, and CO₂, PBR 3: 70% wastewater, 30% dilution water, microalgal inoculum, and compressed air and PBR 4: 100% wastewater, microalgal inoculum, and compressed air. The results demonstrated that nutrient removal efficiency in all four PBRs was optimal, exceeding 90% for total nitrogen and total phosphorus. The highest removal rates were observed in PBR 1, achieving 92% nitrogen and 96% phosphorus removal. In conclusion, microalgae exhibit significant phycoremediation activity, presenting an eco-friendly technology with great potential for further research due to the vast diversity of microalgal species.