Comparative environmental impact evaluation of palm oil mill effluent treatment using a life cycle assessment approach: A case study based on composting and a combination for biogas technologies in North Sumatera of Indonesia

The objective of this study is to use a life-cycle assessment (LCA) to compare and evaluate the environmental impact of combinations of open lagoon technology (COLT) with composting and COLT-Biogas for palm oil mill effluent (POME) treatment in North Sumatera, Indonesia. COLT-Biogas technology consists of three major types: composting, land application, and membrane technology. The environmental impact was evaluated by focusing on global warming potential (GWP), acidification potential, eutrophication potential, human toxicity potential, energy consumption (EC), and net energy ratio (NER). The results presented herein indicate that the GWP was the most significant criteria in the POME environmental impact assessment. With respect to GWP, COLT-Biogas A integrated with composting was observed more environmentally friendly than the other combinations. Approximately 357.18 kg CO2-eq of GWP reduction could be achieved with this technology without considering the utilization potential of its products. With respect to NER, COLT-Biogas B with land application and COLT-Biogas C with membrane technology achieved better results since they do not require fossil fuel input. In terms of EC, COLT Biogas C with membrane technology required the lowest amount of energy among the alternative technologies. A novel approach of comparing POME treatment technologies is presented herein, and the findings could help decision makers and planners to adopt the more environmentally friendly policies, resulting in more sustainable palm oil products. (C) 2018 Elsevier Ltd. All rights reserved.