Life cycle assessment of biogas production from mixtures of vinasse and concentrated latex wastewater

Environmental impacts of biogas production were evaluated by a life cycle assessment (LCA) of mixtures of vinasse and concentrated latex wastewater (CLWW) as: 1) single-stage and two-stage anaerobic digestion with different ratios and initial pH; 2) LCA of thermal energy from biogas. Results showed that almost all two-stage anaerobic digestion processes produced higher amounts of biogas and methane than the single-stage. Environmental impact was assessed for 1 MJ of thermal energy production. Two-stage anaerobic digestion produced less environmental impact in terms of global warming potential (GWP), acidification (AD) and energy use (EU) than single-stage at 64.82, 64.86 and 64.72%, respectively. Anaerobic digestion significantly contributed to environmental impact using sodium hydroxide solution for pretreatment.