Chemicals from biomass – managing greenhouse gas emissions in biorefinery production chains – a review

• Greenhouse gas emissions (GHG) of biorefinery production chains are identified.
• Lignocellulosic, organic waste and algae dominate as feedstock in technology research.
• Uncertainties of GHG emissions concentrate on feedstock supply chain.
• Cultivated crops dominate sustainability and life cycle analysis (LCA).
• The low carbon efficiency of current biorefinery operations is directly linked to the relatively high GHG emissions reported.

Growing concerns over the availability and cost of extracting fossil fuel resources have increased interest in renewable resources. Therefore, interest in producing numerous needed chemicals from renewable biomass resources has increased. The focus of this comprehensive review is on managing greenhouse gas emissions (GHG) in biorefinery production chains. To highlight the results of the content analysis an attempt is made to summarize the findings in a climate impact management matrix. In particular, three topics from the matrix are put forward: (1) uncertainties in assessing GHG emissions of feedstock cultivation, harvesting and logistics; (2) found GHG emissions in biorefinery chains; and (3) a short comparative analysis of two potential technologies to improve the GHG and carbon balance of biorefinery operations. In addition, benefits of lignocellulosic biomass, residuals, organic waste and algae are highlighted, sustainability issues of the field are discussed and research gaps are identified. Uncertainties in assessing the sustainability of biofuels supply chains support a more diversified renewable resource base and production of multiple chemicals in biorefinery chains.