Sustainable management of dairy wastewater through remediation with microalgae

VEZZOSI-ZOTO GINA; SACKS NATALIA AGUSTINA; URBANI MELINA; ZAPATA LUZ MARINA

INTERNATIONAL JOURNAL OF PHYTOREMEDIATION

TAYLOR & FRANCIS INC

Lugar: Londres; Año: 2025

1522-6514

Pollution with industrial wastewater is an urgent environmental problem. The purpose of this research was to study the pollutant removal efficiency from dairy wastewater by using microalgae to evaluate the potential use of the remediated wastewater as irrigation water. Tetradesmus obliquus (To), Chlorella sorokiniana (Cs), and Chlorella vulgaris (Cv) were cultivated in photobioreactors with dairy wastewater at four dilution rates (DR): 0.20, 0.25, 0.30, and 0.35 d-1. Twelve treatments were tested resulting from the combination of three microalgae with four DR. Before and after the phycoremediation process, pH, electrical conductivity (EC), total nitrogen (TN), total phosphorus (TP), chemical oxygen demand (COD), total organic carbon (TOC), Na, K, Ca, Mg, Zn, Fe, Mn, Al, Sr, B, Ba, Cr, Ni, Cd, Pb, Co, Mo, Hg, Ag, As, total coliforms, and Escherichia coli were analyzed. All treatments showed a high efficiency of pollutant removal. However, the best treatment was Cv 0.20, which eliminated 99 % TN, 72 % TP, 57 % TOC, 95 % COD, and 100 % total coliforms and Escherichia coli. Results indicated that remediated wastewater reached discharge standards in water bodies and complied with most irrigation requirements, which could increase the possibilities for sustainable agricultural practices.