Second-generation technology Second-generation biofuels

1 second-generation technology

1.1 thermochemical routes

1.1.1 gasification
1.1.2 pyrolysis
1.1.3 torrefaction


1.2 biochemical routes

second-generation technology

the following subsections describe main second-generation routes under development.

thermochemical routes

carbon-based materials can heated @ high temperatures in absence (pyrolysis) or presence of oxygen, air and/or steam (gasification).

these thermochemical processes both yield combustible gas , solid char. gas can fermented or chemically synthesised range of fuels, including ethanol, synthetic diesel or jet fuel.

there lower temperature processes in region of 150–374 °c, produce sugars decomposing biomass in water or without additives.

gasification

gasification technologies established conventional feedstocks such coal , crude oil. second-generation gasification technologies include gasification of forest , agricultural residues, waste wood, energy crops , black liquor. output syngas further synthesis e.g. fischer-tropsch products including diesel fuel, biomethanol, biodme (dimethyl ether), gasoline via catalytic conversion of dimethyl ether, or biomethane (synthetic natural gas). syngas can used in heat production , generation of mechanical , electrical power via gas motors or gas turbines.

pyrolysis

pyrolysis established technique decomposition of organic material @ elevated temperatures in absence of oxygen. in second-generation biofuels applications forest , agricultural residues, wood waste , energy crops can used feedstock produce e.g. bio-oil fuel oil applications. bio-oil typically requires significant additional treatment render suitable refinery feedstock replace crude oil.

torrefaction

torrefaction form of pyrolysis @ temperatures typically ranging between 200–320 °c. feedstocks , output same pyrolysis.

biochemical routes

chemical , biological processes used in other applications being adapted second-generation biofuels. biochemical processes typically employ pre-treatment accelerate hydrolysis process, separates out lignin, hemicellulose , cellulose. once these ingredients separated, cellulose fractions can fermented alcohols.

feedstocks energy crops, agricultural , forest residues, food industry , municipal biowaste , other biomass containing sugars. products include alcohols (such ethanol , butanol) , other hydrocarbons transportation use.