Little Falls, Minn. — The nation’s first commercial cellulosic ethanol plant could be going up in central Minnesota — if a feasibility study looks favorable.
In May, Central Minnesota Ethanol Cooperative expects to complete an evaluation of building a cellulosic plant by its corn ethanol plant near Little Falls.
The locally-owned CMEC plant produces about 21 million gallons of corn ethanol annually. Kerry Nixon, CMEC general manager, says if the feasibility and financial evaluations look favorable, the cooperative could add a 10-million-gallon facility that converts wood and other biomass to ethanol.
“For us to expand (corn-ethanol production), we would have to compete for corn with other existing plants,” Nixon says. “Since we’re in the region of lakes and trees, it makes sense for us to look at other options.”
“Central Minnesota Ethanol has been innovative since their inception,” says Michael Sparby, AURI project director. “Given their location at the northern end of Minnesota’s corn range, they have to be creative and innovative if they want to grow.”
AURI is supporting technical and economic feasibility studies of the cellulosic facility. CMEC has also received funding from Minnesota’s Next Generation Energy Board.
Since 2007, CMEC has been working with Bell Independent Power Company and SunOpta BioProcess, Inc. to jointly build, own and operate the plant that would be one of the first commercially-viable cellulosic plants in the world. Based in Toronto, SBI has more than 30 years of biomass experience and is making ethanol in Spain and finalizing plans for a large facility in China, Nixon says.
The Little Falls facility would use SBI’s proprietary process for pretreatment, using heat and steam to partially hydrolyze lignocellulosic fibers so they can be fermented for ethanol. Residual lignin will be gasified to power both the new cellulosic facility and the existing ethanol plant.
The cellulosic plant will use soft hardwoods such as poplar and aspen trees harvested in a 70-mile radius of Little Falls. Chips from green-cut trees contain about 50 percent moisture, which the SBI process captures and uses, so outside water is not needed for fermentation. Nixon says the process may capture enough moisture to offset some of the corn-ethanol plant’s needs as well.
CMEC has been producing corn ethanol since 1999. “There are synergies here because we have the land, the power — plus the maintenance and marketing pieces are already in place,” Nixon says.
“After the preprocessing, fermentation is about the same for starch or cellulose, but the cellulosic process resolves a lot of the energy and water issues associated with ethanol.”
If CMEC decides to pursue a cellulosic plant, it will take about 16 months to complete. “They’re more expensive than starch plants, but the operational costs are cheaper,” Nixon says.
Sparby says a cellulosic ethanol plant will “bring Minnesota to the next level of biofuels development.”