Chapter 1 - Principles of Biorefining

Abstract

This chapter presents the principles of biorefining. The biorefinery concept embraces a wide range of technologies able to separate biomass resources (wood, grasses, corn, etc.) into their building blocks, (carbohydrates, proteins, fats, etc.) which can be converted to value-added products, biofuels, and chemicals. A biorefinery is a facility (or network of facilities) that integrates biomass conversion processes and equipment to produce transportation biofuels, power, and chemicals from biomass. The biorefinery concept is analogous to today's petroleum refinery, which produces multiple fuels and products from petroleum. The elemental and chemical structure of biorefinery raw materials differs from that on which the current fossil refinery and chemical industry is based. Chemical and elemental composition of petroleum is compared with some lignocellulosic biomass feedstocks in feedstock is that, unlike biomass, it is very low in oxygen content. Biomass is constituted of an enormous variety of plant species with varying morphology and chemical composition. However, regardless of the phenotype, five main biomass components can be identified worldwide: lipids, starch, cellulose, hemicelluloses, lignin, and proteins. It clearly appears that lignocellulosic biomass components such as cellulose, hemicelluloses, and lignin are by far the most abundant. Since they can be even gathered from waste streams (e.g., crop residues, paper and wood industries), or directly harvested from forests or biomass stands through sustainable management, their price tend to be lower than other biomass sources which need a dedicated agricultural plot.