Evaluating the environmental sustainability of biochemicals
With efforts aimed at moving towards a global bio-based economy, the production of fuels and chemicals in biomass-based biorefineries is gaining traction. Agro-industrial residues or agricultural crops, municipal solid waste and forestry waste are considered to be the most significant feedstocks for such biorefineries in tackling climate change, ensuring food security, creating sustainable raw materials and diversifying energy resources. In general, biochemicals are seen as environmentally sustainable because they are bio-based. However, is that really the case? The answer isn’t straightforward, according to researchers who highlight the importance of the LCA concept in two recent studies. Supported by the EU-funded BIOREFINE-2G project, the studies emphasise the need to consider the entire life cycle of products in the development of biochemicals. LCA, a widely used methodology for assessing environmental sustainability, takes into account the impact of all physical and economic processes and products that are directly or indirectly involved in the life of the biochemical, from the excavation/recovery of raw materials to the disposal stage – recycling or incineration. In a study published in the journal ‘Nature Sustainability’, the researchers state: “We analysed LCA studies applied to commercialized commodity biochemicals produced through microbial fermentation. The few available studies show inconsistencies in coverage of environmental impacts and life cycle stages, with varying conclusions.” They add: “Claims of better sustainability performance of biochemicals over fossil-based chemicals are often based on comparing global warming impacts, while ignoring other impacts from bio-feedstock production. To boost sustainable biochemicals, we recommend that LCA practitioners include the broader range of impact indicators and entire life cycles, follow standards and guidance, and address missing data.” The researchers conclude that LCA should be utilised systematically “to direct research, identify impact hotspots, and develop methods to estimate full-scale process performance. This will promote biotechnology as [an] important contributor to solving existing sustainability challenges.” Quoted in a news release, lead author Ólafur Ögmundarson from The Novo Nordisk Foundation Center for Biosustainability says: “The fact that something is ‘bio’ doesn’t always mean that it is better. It depends primarily on modes of production conditions and energy usage at various life cycle stages. Therefore, in general, we need to think and assess the whole life cycle of the product to identify their impacts.”
Lactic acid
In a study published in the journal ‘GCB Bioenergy’, the researchers focus on biochemical lactic acid that is mostly used for the production of bioplastics. “Lactic acid (LA) was used as an example biochemical derived from corn, corn stover, and macroalgae (Laminaria sp.) as feedstocks of different technological maturity. We used environmental life cycle assessment (LCA), a standardized methodology, considering the full life cycle of the analyzed biochemical production systems and a broad range of environmental impact indicators.” The researchers conclude that “applying LCA in a comprehensive manner gives the bio-based industry the opportunity to actively incorporate and prioritize environmental sustainability in its decision-making process at an early stage of development of biochemicals.” The BIOREFINE-2G (Development of 2nd Generation Biorefineries – Production of Dicarboxylic Acids and Bio-based Polymers Derived Thereof) project ended in September 2017. It developed novel and commercially attractive processes to convert pentose-rich side streams from biorefineries into biopolymers. For more information, please see: BIOREFINE-2G project website
Countries
Denmark
