Environmental performance of the innovative, patented mixing system in an agricultural biogas plant based on LCA approach

Abstract

Renewable energy production in biogas plants seems to be recognised in literature from the environmental perspective. However, innovative technologies are still launched to improve energy efficiency. In this perspective, the authors developed the patented hybrid pump to improve the yield of methane production and reduce the environmental impact of renewable energy production. This research assesses the environmental performance of an innovative, patented hybrid pump designed for mixing the input of anaerobic digestion of pig slurry, based on the Life Cycle Assessment (LCA) approach. The comparative environmental analysis of two different mixing systems installed in the pilot biogas plant was conducted on the basis of the selected impact categories. The application of innovative mixing technology with a hybrid pump increased the percentage yield of methane in biogas from slurry by about 10% compared to a conventional hydraulic pump. The application of a hybrid pump in the tested biogas plant reduced the Cumulative Energy Demand (CED) ratio by almost 30% compared to a conventional hydraulic pump. A similar level was obtained for other environmental impact ratios in terms of global warming potential, abiotic depletion of fossil fuels, human toxicity, acidification, and eutrophication.