Life cycle assessment of a novel biomass-based aerogel material for building insulation

Abstract

There is a growing interest in accounting for the environmental externalities and the greenhouse gas (GHG) emissions associated with the building industry. This study examines the life cycle environmental impacts of a novel biomass-based aerogel building material manufactured via freeze drying method comprising of three process stages, i.e., gel preparation, aging and freeze drying. The main focus of this study is to evaluate the contribution of each stage to the environmental load using life cycle assessment tool, figure out the main stage that has the greatest impact on the environment and propose some potential improvements by critical analysis of the production process. Life cycle impact scores are quantified as per functional unit of 1 m3 biomass-based aerogel for six midpoint impact categories (climate change potential, non-renewable energy potential, stratospheric ozone depletion, terrestrial acidification potential, terrestrial ecotoxicity and aquatic ecotoxicity). The respective LCA scores for these categories are depicted as 6.76E+02 kg CO2 eq., 1.65E+04 MJ, 4.21E-04 kg CFC-11 eq., 8.57E+00 kg SO2 eq., 2.07E+03 kg TEG soil and 9.87E+03 kg TEG. While comparing individual process substages, the freeze drying stage of the manufacturing process presents the highest overall impact contribution. Comparative environmental scoring with other aerogel types further reveals that the biomass-based aerogels are environmentally promising alternatives. Since the production is done at a laboratory scale, these results can be regarded as a conservative estimate, however they can act as steppingstones for process optimization for commercial scale manufacturing.