Page 236 - Biosystems Engineering

214 Cha pte r Se v e n

It was used more than 38,000 years ago by the Cro-Magnon people to
create the magnificent drawings in the Grotte Chauvet (Antal and
Gronli 2003). Egyptian mummy makers used the tars and the pyrolyg-
neous acids resulting from biomass pyrolysis to practice their craft. In
the nineteenth and early twentieth centuries, the biomass pyrolysis
(wood distillation) was a profitable business producing soluble tars,
creosote oil, methanol, and acetone (Klar and Rule 1925). By the 1930s,
the wood-distillation industry entered a period of steady decline due
to the fierce competition from cheaper petroleum-derived products.
Fast pyrolysis technologies were developed in the 1970s to maxi-
mize the production of crude bio-oils. One of the main advantages of
producing crude bio-oil is that this energy-densified liquid can be
transported from the processing unit to distant power stations or to
bio-oil refineries (Peláez-Samaniego et al. 2008). Thus, it is possible to
visualize the creation of a new model of biomass economy (see Fig. 7.1)
formed by distributed pyrolysis units located close to biomass
resources and centralized refineries where second-generation trans-
portation fuels and high-value chemicals can be produced, taking
advantage of the economies of scale. Fast pyrolysis can convert up to
75 mass% of the biomass into crude bio-oils. Forty percent of these oils
could be further transformed into green gasoline and green diesel via
bio-oil hydrotreatment (Holmgren et al. 2008; Elliott 2007). An advan-
tage of this new model of biomass economy is that it can make good
use of the existing infrastructure created by the petroleum industry.

Mobile Biomass
Biomass pyrolysis units

Biomass
Bio-oil Bio-oil Charcoal
Charcoal Biomass
Bio-oil
Bio-oil
Charcoal Charcoal
Bio-oil
Biomass Bio-oil refineries
Bio-oil
Bio-oil Biomass
Bio-oil
Charcoal
Charcoal
Biomass

Charcoal Charcoal
Biomass
FIGURE 7.1 New model of biomass economy formed by distributed pyrolysis units
and bio-oil refi neries.