Assessment of Conversion Technologies for Bioalcohol Fuel ...

syngas to bioalcohol and electricity co-production systems. It is expected that the
bioalcohols directly produced from these thermochemical processes will be comprised
of an 80-85 % ethanol/10-15% methanol mix, with smaller percentages of other higher
alcohols possibly present as well. Distillation can be employed to separate ethanol
from such a mixed alcohol product if necessary. However, this adds to the costs,
energy intensity and environmental impacts of the production facilities, and therefore is
best avoided. Thus, steps to gain acceptance of mixed alcohol fuels by the
automotive industry and regulatory agencies must also be pursued to fully realize the
opportunity these technologies represent for bioalcohol fuel production.
The 5E assessment indicates that the above thermochemical process will be capable
of producing bioalcohols in facilities using as little as 250 dry tons (DT) per day of
biomass at a production cost of less than $1.50/gallon. Furthermore, this process
should be able to produce ethanol at an average of $1.12/gallon for a 500 DTPD plant.
Improvements in this thermochemical technology have the potential of reducing
ethanol production costs to below $1.00/gallon by 2012, where biomass feedstock can
be supplied at $35/ DT.
Other thermochemical conversion processes that incorporate air or oxygen typically
produce syngas that has a low BTU value (