Life cycle assessment of microalgae products : state of the art and their potential for the production of polylactid acid

Kurzfassung/Abstract

Microalgae can play a key role in overcoming the shortage of biomass in the European bioeconomy. This study evaluates the potential of using microalgal residues from the production of lipopeptides as a feedstock for polylactic acid. In order to investigate the environmental potential of the proposed multi- output product system, eight different studies on microalgae production and application as well as 12 investigations on polylactic acid production and disposal were analysed to identify environmental strengths and weaknesses. A pedigree matrix was developed to assess the significance of the findings of each study. The results suggest that microalgae could potentially reduce several of the major environmental hot spots of polylactic acid production. A high improvement potential was found for land use and terrestrial ecotoxicity, which could result in environmental advantages of microalgae-PLA blends over conventional plastics. For eutrophication, human toxicity, photochemical oxidant formation and acidi- fication lower amelioration potentials were identified. For the remaining impact categories, the results showed no enhancement or even the risk of worsening the environmental performance of polylactic acid. Further research, however, is necessary to optimize the growing conditions of algal biomass and to investigate the effects of microalgae on the properties of polylactic acid.