Page 456 - Refining Biomass Residues for Sustainable Energy and Bioproducts

414 Refining Biomass Residues for Sustainable Energy and Bioproducts

Table 18.1 Different important key stages of anaerobic digestion, bacterial genera used for
their respective process, and their general equation.

S. Key stages Bacterial genera General equation
no.
1 Enzymatic Bacillus nC 6 H 10 O 5 1 nH 2 O ! nC 6 H 12 O 6
Hydrolysis Cellulomonas
Eubacterium
2 Acidogenesis Propionibacterium nC 6 H 12 O 6 ! nR 2 COOH
Butyrivibrio nC 6 H 12 O 6 ! nR 2 OH
Acetivibrio
3 Acetogenesis Syntrophomonas nC 6 H 12 O 6 ! 3nCH 3 COOH
Syntrophobacter
4 Methanogenesis Methanobacterium CH 3 COOH ! CH 4 1 CO 2
Methanogenia CO 2 1 4H 2 ! CH 4 1 3H 2 O
Methanococcus
Methanospirillum
Archaea

A mix of a couple of system steps (e.g., mechanical procedures, such as crushing, and
thermochemical forms, for instance, gasification)
The use of different unrefined materials from both virgin and remaining sources

18.5.2 Biomass chain

Biomass involves a high substance of cellulose, proteins, hemicellulose, lignin, and
extractives, subsequently shaping a characteristic inexhaustible asset for an eco-
accommodating economical and feasible material. By obtaining biomass either
from the manufacturing industries (especially food industry) or as a product from
the fermentation or the microbial cultivation process, the biorefinery process takes
place by interacting with them and converting the waste products into valuable pro-
ducts. There are three possible ways through which biomass obtained as a product
include pretreatment of FW obtained from the manufacturing industries through
biological, physical, and mechanical processes and fermentation and microbial cul-
tivation of yeast and microalgae. The product from these processes can be con-
verted into useful products through biorefinery techniques by catalytic conversion
and separation process. The different products are obtained through the conversion
of biomass, such as biofertilizer, biofuel, bioplastics, biochemicals (bulk and fine
chemicals), solvents, fibers, and oils (Weiland, 2010).

18.6 Food-waste biorefinery

FW can fill in as fundamental substrates for the phase of various things, namely,
algal biodiesel, biocontrol, bioexcrements, and bioplastics. The need for