Page 437 - Refining Biomass Residues for Sustainable Energy and Bioproducts

396 Refining Biomass Residues for Sustainable Energy and Bioproducts

flexible with more product formation to maintain the economic status of biorefin-
ery. The wet milling process of corn produces a wide range of products, such as
lactic acid, corn syrup, and corn oil. Phase I possesses no such potential to maintain
the same level of profit. Phase III biorefinery is much more flexible than the other
two phases of biorefinery. Along with the production of various valuable products,
this phase has the potential to utilize different varieties of feedstock and processing
approaches. This phase is advantageous for the processing of food waste with utili-
zation of multidisciplinary techniques. The potential to utilize variety of the feed-
stock is the master stroke of this phase, which ensures continuous supply of
material for the process at every time to improve the economical benefits.
Biomass possesses complex chemical components with different physical proper-
ties, which decide the final product formation and techniques come into play.
That’s why it is necessary to maintain the database related to physical properties
along with chemical components for the growth of biorefinery based on food waste.
It is beneficial to utilize a combination of feedstocks for the production of biofuels
and biomaterials.
According to the requirement of the final product from the biorefinery, there are
two types of approaches for the product substitution, that is, direct and indirect. The
approach of direct product substitution explains the already existence of the final
product in market and that product needs to be manufactured through a novel pro-
cess. There is no difficulty in the acceptance of the product in the market as the
product already possesses a market value (Clark et al., 2006). For the acceptance
and high market value of indirect product the cost of indirect product should be low
along with the property of better performance as compared to existing product.
Instead of forming final product, the intermediate chemicals may also be act as
master piece to form new compounds via coupling with existing chemicals for their
value addition (FitzPatrick et al., 2010). Production of butanol from food wastes
through anaerobic fermentation is a better example of intermediate chemical as it is
widely used for the production of acrylate and acetate (Huang et al., 2015).
During biorefinery processing, mechanical treatment, such as pressing, milling,
and pelletization, of the waste is the first step to reduce the size of particles for bet-
ter mass transfer, enzymatic hydrolysis along with biological degradation of bio-
mass. That treatment has no effect on the composition of the biomass (Menon and
Rao, 2012). Chemical treatments, such as transesterification, hydrolysis, oxidation,
and hydrogenation, come into play to alter the composition of biomass (Cherubini,
2010), for example, the process of transesterification leads to the production of bio-
diesel by utilizing vegetable oils. Some complex compounds, such as cellulose and
hemicellulose, are enzymatically hydrolyzed into their basic components, such as
glucose, xylose, which act as beneficial components for biofuel production, such as
ethanol and butanol.
A huge amount of plant-derived food waste is generated annually because of
concern farming field activities and food processing. With a high stability and a
great amount of waste generated from agricultural field, such as wheat and rice
straw, along with corn stover are the most promising feedstocks for biorefineries on
industrial scale (Kamm and Kamm, 2004). Beverage industry is the second most