Assessment of Conversion Technologies for Bioalcohol Fuel ...

CATEGORY VIII–BIOCHEMICAL PROCESSES
INCORPORATING ACID HYDROLYSIS/FERMENTATION
Blue Fire Ethanol, Inc., Irvine, California
Organizational Background–Originally formed in 1992 as Arkenol, Inc., BlueFire
Ethanol is the operating company established to deploy the patented Arkenol
Technology for producing ethanol from biomass. The original parent company, ARK
Energy (since acquired by Tenneco, Inc.), developed electric power cogeneration
projects. In 1994, Arkenol, in partnership with Sacramento Municipal Utility District
(SMUD), was granted certification by the CEC for the Sacramento Ethanol and Power
Cogeneration Project (SEPCO), a joint-venture intended to produce ethanol and
electricity from rice straw and other agricultural wastes. However, the Arkenol/SMUD
partnership dissolved and the project was not constructed.
Technology Characteristics–The Arkenol Technology, illustrated in Figure A8, is a
concentrated acid hydrolysis process, incorporating various technological
improvements to traditional hydrolysis, along with modern control methods, and newer
materials of construction. One particular innovation is use of commercially available
ion exchange resins to separate the sugars produced in the process from the acid
solution, which is then re-concentrated and recycled. Lignin is also separated from the
hydolyzate for use as a boiler fuel.
In a full commercial application, the process would involve a sequence of the following
six steps for producing ethanol from cellulosic biomass feedstocks:
1. Feedstock preparation
2. De-crystallization/hydrolysis reaction vessel
3. Solids/liquid filtration
4. Separation of the acid and sugars
5. Fermentation of the sugars
6. Product purification
The technology is said to be extremely versatile, both in its ability to utilize a wide
variety of feedstocks and in the end-products that it can produce. All of the feedstock
used in the process is intended to be converted to saleable products, including:
ethanol, lignin, gypsum, and animal yeast. In the presence of a viable market, carbon
dioxide may also be captured and sold as a byproduct of the process.
Development Status–BlueFire’s technology has undergone twelve years of
progressive development involving several stages of pilot plant operations. The first of
these was conducted at the company’s own research facility in Orange, California,
where a 1 ton-per-day batch facility was employed for testing from 1994 to 1999.
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