Comparative assessment of Chlorella minutissima, Chlorella sorokiniana, and Scenedesmus abundans based phycoremediation for pollution reduction in dairy industry wastewater

Dairy industry is one of the major sectors of food industries, known for high water consumption and discharge of nutrient rich wastewater. This dairy wastewater (DWW) contains high levels of pollutants such as fats, oils, and grease (FOG) total suspended solids (TSS), nitrogen compounds, and phosphorus. If this wastewater is left untreated or improperly managed, DWW can lead to severe environmental concerns, including eutrophication of water bodies and degradation of aquatic ecosystems. These challenges underscore the need for sustainable and efficient biological treatment approaches to ensure environmental protection and water resource sustainability. Hence, this study presents the effect of different freshwater microalgae including Chlorella minutissima, Chlorella sorokiniana, and Scenedesmus abundans on phycoremediation of DWW. The experiments were conducted using 100% dairy wastewater (DWW 100) and different blends of DWW with BG-11 culture media. The results revealed that the phycoremediation efficiencies of C. minutissima was maximum (COD: 96%, BOD: 41%) while S. abundans showed minimum phycoremediation efficiency (COD: 95%, BOD: 22%). This study would contribute to achieve sustainability development goals (SDGs) (3, 6, 13, 14) being a zero-waste technology with zero liquid discharge (ZLD).