Page 269 - Synthetic Fuels Handbook

FUELS FROM BIOMASS 255

Agricultural biomass Forest biomass Urban biomass Legend

Harvesting
Dedicated Dedicated
crops trees
Processing/
Primary Recovered recovery
products Residues (2) biomass
Residues
(2)

Biomass
Lignocellulosic-based

Primary
Fast pyrolysis
processing

Fractionation
Boiler
Upgrade Reform
Engine/ Secondary
turbine Gasify processing

Synthesis Tertiary
processing

Product recovery

Chemicals Heat Electricity Bio-oil Biosyn fuels H 2 Product decision
FIGURE 8.10 Thermochemical platform flowchart.

products are more likely to be gaseous and consist of carbon monoxide, hydrogen, methane,
carbon dioxide, and water as well as volatile tar.
Slow pyrolysis, like fast pyrolysis, leaves behind a solid residue of char (or charcoal)
which comprise approximately 10 to 25 percent by weight of the original feedstock. The
char can be used as a fuel source to drive the pyrolysis process. If the pyrolysis is carried
out at a higher temperature range (550–600°C), the gaseous products consist of carbon
monoxide, hydrogen, methane, volatile tar, carbon dioxide, and water. Any char produced
can be used as a fuel source to drive the pyrolysis process or can be gasified to produce