Page 32 - Lignocellulosic Biomass to Liquid Biofuels

Fundamentals of lignocellulosic biomass 11

Figure 1.2 Conceptual difference between petroleum refinery and the biorefinery.

1.5 Biorefinery of lignocellulosic biomass
The biorefinery is a facility that integrates biomass conversion processes
and equipment to produce fuels, power, and chemicals from biomass,
using a variety of different technologies. Consequently, the concept of
biorefinery, now widely accepted, is analogous to that of petroleum refin-
ery (Fig. 1.2), except that it makes use of renewable plant-derived materi-
als (derived from photosynthesizing plants), whereas an oil refinery uses
nonrenewable fossil-derived petroleum.
The technologies based upon the concept of biorefinery can provide a
wide range of bio-based products that include biofuels (bioethanol, bio-
diesel, and biomethane), biomaterials (fibers, pulp for paper manufacture,
composite compounds, lignin-based hydrogels, etc.), and a host of bio-
chemicals through downstream fermentation and refining processes.
Therefore LCB has a wide range of application as the alternative to petro-
leum for the generation of biofuels and chemicals, which makes it a rec-
ognized and valuable commodity all over the world.
Effectivelybreakinglignocelluloserecalcitrance, releasing monomer from
the long-chain polymeric sugars, and coutilization of lignocellulose compo-
nents are the largest technical and economical challenges for the biorefinery
of LCB. Fractionation of LCB is really a tough task because of its complex
structure and composition constituent [19]. Moreover, it is the first step of
biorefinery to get fuels, chemicals, or materials from LCB. The fractionation
routes and their process conditions are summarized in Table 1.3.
Organosolv fractionation (OF) is a unique and one-step process for
fractionating the LCB to produce cellulosic fibers, hemicellulose sugar,