CMEC, SunOpta to build cellulosic ethanol plant

By Jessica Sobolik | January 01, 2008
In November, SunOpta BioProcess Inc., a subsidiary of SunOpta Inc., signed a letter of intent with Central Minnesota Ethanol Co-op in Little Falls, Minn., to complete feasibility and engineering studies that may lead to the two companies jointly building, owning and operating a 10 MMgy cellulosic ethanol plant. The facility would be adjacent to CMEC's existing corn-to-ethanol plant and would use local wood chips as a feedstock, provided final engineering and definitive agreements are completed.

The critical pretreatment process step will utilize SunOpta BioProcess' patented auto hydrolysis process, which uses steam explosion technology to pretreat and partially hydrolyze lignocellulosic materials. In this process, no external chemical catalyst is required, and the water contained in the feedstock is efficiently used, eliminating the need for large external water sources. This technology is currently being used in a number of demonstration-scale cellulosic ethanol plants around the world, according to SunOpta.

The proposed facility would initially produce 10 MMgy of cellulosic ethanol with modular scale-up plans to expand to more than 50 MMgy. The wood waste feedstock supply would also be used in CMEC's biomass gasifier, which started operating in the fall of 2006, to provide power to both plants.

"We anticipate powerful synergies with CMEC's management and operations expertise, excellent existing infrastructure and strong community relationships," said Murray Burke, president of SunOpta BioProcess. "We expect the planned cellulosic ethanol facility to be one of the first of its kind in the world, bringing the commercial production of cellulosic ethanol to reality. This venture is consistent with [SunOpta's] long-term strategy of leveraging our proprietary technology in the ownership and operation of leading-edge cellulosic ethanol operations."

On Oct. 28, a minor fire and explosion occurred in a wood chip storage silo for the biomass boiler at CMEC's corn-based plant. There were no injuries, and no damage was sustained in the rest of the facility. The cause wasn't immediately determined. After a brief shutdown, it was on line one day later.