LIFE CYCLE ASSESSMENT OF WASTEWATER FROM DAIRY INDUSTRY

Abstract

In this study, life cycle assessment (LCA) was used to investigated the environmental impacts associated with dairy wastewater treatment. The composition of dairy wastewater was investigated by applying various water quality methods. Indicators like pH, suspension, chemical oxygen demand (COD), biochemical oxygen demand (BOD), extractable substances, detergents, sulfates (SO₄^2-), nitrates (NO₃^-), nitrites (NO₂^-), N, P and others were determined. Also, the composition of treated water, at the exit of the treatment plant, was established. Monitoring of the effluent composition was performed for three years, the determinations being performed every month in triplicate. For the environmental inventory analysis, the average of the values obtained for quality indicators in 2015 was considered, the year in which the highest values for the quality indicators were registered. GaBi software was used for the environmental impact calculation. Results showed that treatment of dairy wastewater influences mostly the eutrophication potential. Other impact categories are mainly influenced by electricity production for consumption in the wastewater treatment process. It was observed that acidification potential has the highest value, followed by the global warming potential, the photochemical ozone formation potential, and human toxicity potential, respectively.