Glossary - Biomass Gasification, Pyrolysis and Torrefaction - page 494

Lignin A component of the cell wall of wood. It is a complex polymer that binds cellulose
cells in biomass.
Methanol An important alcohol (CH 3 OH) that serves as a feedstock for a host of chemicals
and liquid transportation fuels.
Polymerization The building up of larger molecules by combining smaller molecules that
is necessarily similar.
Producer gas Primarily a mixture of carbon monoxide, hydrogen, and nitrogen produced
by blowing air and steam through the fuel bed.
Protein Any organic compound made up of amino acids arranged in a linear chain and
folded into a globular form. These high-molecular-weight compounds of carbon,
hydrogen, oxygen, and nitrogen are synthesized by plants and animals.
Reforming The structural manipulation of a molecule to improve its product quality. The
process does not always involve major change in the molar mass. The steam reforming
of methane is a widely used method of producing hydrogen.
Starch A polysaccharide carbohydrate consisting of a large number of glucose units
joined together by glycosidic bonds, with the generic formula (C 6 H 10 O 5 ) n . All green
plants produce starch for energy storage.
Steam reforming A method for producing hydrogen from methane. Steam reacts with
methane to produce hydrogen and carbon monoxide when heated to very high tempera-
tures in the presence of a metal-based catalyst.
Substituent An atom or a group of bonded atoms that can be considered to have replaced
a hydrogen atom in a parent molecular entity.
Sugar Any monosaccharide or disaccharide used especially by organisms to store energy.
Glucose (C 6 H 12 O 6 ), a monosaccharide, is the simple sugar that stores chemical energy
that biological cells convert to other types of energy.
Syngas A mixture of carbon monoxide and hydrogen.
Synthesis The building up of larger molecules from smaller ones. The molecules being
synthesized need not be similar.
Synthetic natural gas (SNG) A methane gas artificially produced from other gaseous,
solid, or liquid fuels using various methods.
Triglycerides A glyceride in which the glycerol is esterified with three fatty acids; the
main constituent of vegetable oil and animal fats. The chemical formula is RCOO—
CH 2 CH (—OOCR 0 )CH 2 —OOCR v , where R, R 0 , and R v are longer alkyl chains.
Torrefaction Dictionary meaning is roasting, but here it refers to thermal decomposition
within 200 300 C temperature in an oxygen-starved environment.