Assessment of Conversion Technologies for Bioalcohol Fuel ...

The data in Table 5 are based upon thermochemical technologies that process 500
BDT/day and biochemical technologies that process 2,205 BDT/day of biomass. It
would be preferable to compare similar size plants (e.g., 500 BDT/day), but sufficient
data are not available at this time for biochemical conversion plants smaller than 2,205
BDT/day. The application of 5E assessment methodology to the technologies
compared in Table 5 is discussed further in the following sections.
Technology Evaluation (E1)
Thermochemical System (Mixed Alcohols and Electricity)
Several companies have developed varying approaches and improvements in
feedstock introduction, pyrolysis/steam reforming processes, syngas purification and
system design. The data presented for System A in Table 5 is for the thermochemical
conversion of 500 BDT/day of biomass using a generic integration of the
pyrolysis/steam reforming process with catalytic processes recently developed for the
co-production of alcohols, electricity and heat as an example.
Biochemical System (Ethanol and Electricity)
The “5E” assessment was caried out for the Category IX technology (enzymatic
hydrolysis/fermentation). The data presented for System B in Table 5 is for the
biochemical conversion of 2,205 BDT/day of biomass using an enzymatic
hydrolysis/fermentation process. The values presented are an average of data
obtained from several developers of this technology (Schuetzle, 2007).
Thermochemical System (Electricity)
The data presented for System C in Table 5 is for the thermochemical conversion of
500 BDT/day of biomass to electricity (only) using the pyrolysis/steam reforming
technology. This analysis was based upon similar data inputs and assumptions used
for System A.
A major requirement for the deployment of any of these advanced technologies is that
they be able to produce bioalcohols and energy continuously and reliably, for example
for 329 days/year, 24 hours/day. The requirement that these technologies maintain
90% up-time is directly related to the economic efficiency of the facility. These
stringent operational requirements will necessitate that every component in the
production plant be designed with a high level of durability, that the conversion
system(s) have modular designs, and are configured for easy repair.
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