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16 Bioreactors for the Production of Industrial Chemicals and Bioenergy Recovery from Waste

Feedstock

Bio-refinary

Bioproducts

Biochemicals

Biomaterials

Thermal

energy

Biofuel

Thermochemic

al conversion

Biochemical

conversion

Microbial

fermentation

Mechanical

conversion

Grining

Bioethanol

Biohydrogen

Biobutanol

Biogas

Proteins

Polyphenols

Essential oils

Hydrocolloids

Enzymes

Organic acids

Textile

Nanofibres

Heat

Electricity

Steam

Milling

Drying

Pyrolysis

Hydrothermal

liquefaction

Hydrothermal

gasification

Gassification

Enzymatic

hydrolysis

Microbial

hydrolysis

Anaerobic

digestion

Acetogenesis

Acidogenesis

Methanogenesis

Switch grass

Miscanthus

Poplar

Willow

Fruit waste

Vegetable waste

Beverage waste

Straw

Stover

Wood chips

Saw dust

Microorganism

Micro algae

Other waste

Manure

Sewage

Municipal solid

waste

Figure 16.1

Potential feedstock, conversion technologies, and products.

in a four-stage compound procedure ensuring primarily the production of biogas.

A pretreatment step that approved either biologically, chemically, or physically can

go before the authentic AD procedure in order to effectively arrange substrates with

complex structure such as lignocelluloses [5]. In AD practice, kinetics is determined

by the nature of substrates and the physico-chemical parameters such as the pH,

temperature, and hydraulic retention time (HRT). The end product generated

during the splitting of the solid wastes during AD consists of monomers, and these

were generated from complex substrates due to hydrolysis by the enzymes such as

amylases, lipases, and proteases, and these enzymes were produced by the microbes

present in the waste [6]. In the second stage, acidogenic microbes formed in the

first step convert the soluble products into biomolecules, such as alcohols, VFAs,

hydrogen (H2), and carbon dioxide (CO2). The methanogens pursue mainly the

acetotrophic (aceticlastic) and Wood Ljungdahl pathways for production of CH4