Perspectives for scale up of biorefineries using biochemical conversion pathways: Technology status, techno-economic, and sustainable approaches

Abstract

The development of a biobased environmentally sustainable economy will depend on the correct choices of options at several levels. This should include a proper choice of biomass, overcoming the bottlenecks of pretreatment processes, reduction in costs and increasing effectiveness of hydrolytic enzymes, use of genetic and metabolic engineering for increasing the yields of the biocatalysts involved, and addressing environmental, economic, and social sustainability simultaneously. High capital and operating costs, technical immaturity, and scale up challenges are the major road blocks to industrial biorefining processes. This review article highlights the factors that need to be taken into account in the selection and harvesting of lignocellulosic biomass for bioproducts valorization in a carbon neutral manner. Bioethanol production from lignocellulosic biomass is analyzed and alternative routes for the production of platform chemicals are recommended. The need for simultaneous Techno Economic Analysis (TEA) and Life Cycle Assessment (LCA) along with monetization of the environmental effects to make such processes competitive is stressed. Utilization of all three major components of biomass in a specific industry will be needed for profitable biorefining facilities using lignocellulosic residues. A comparison of scenarios in which the hemicellulose and lignin streams are used for the production of alternate co-products and energy along with the main C-6 sugar based product is emphasized.