A Straighter, Shorter Pathway
by Sue Retka Schill (Biomass Magazine) Seven years after the U.S. EPA published the final rule for administering the Renewable Fuel Standard, the path to getting corn kernel fiber-to-cellulosic ethanol approvals appears to be getting much shorter. Edeniq CEO Brian Thome reports it now takes six weeks from the time the data is submitted to the EPA to the time approval is granted to generate D3 RINs (renewable identification numbers). For those plants with efficient producer status, an amended petition process will take another six weeks.
That’s a far cry from the nearly three years it took for the first two companies, Quad County Corn Processors and Edeniq, to get corn kernel fiber approved as a feedstock.
The big difference is that QCCP’s cellulosic process occurs in a separate system, making the cellulosic ethanol measurement straightforward. Edeniq’s Pathway involves coprocessing, with the cellulases added to the starch fermentation tank. Though it consists of a simple addition of enzymes, the intellectual property is in the protocols and tests to quantify the cellulosic lift. “It took years and millions of dollars for our scientists to come up with a very precise and accurate way to measure what’s happening with those conversions,” Thome says.
LSCP (Little Sioux Corn Processors) has been using cellulase enzymes for a couple of years, working with Archer Daniels Midland Co. on trials for ADM’s Clintozyme, says Steve Roe LSCP’s general manager. The cellulase enzyme boosted ethanol yields to better than 2.9 gallons per bushel, Roe says, and improved corn oil yield. Then the company decided to go after the cellulosic ethanol gain. It licensed the Edeniq Pathway, and worked with Edeniq to establish the cellulosic lift.
Once EPA decided how to handle the D3 gallons in the EP3 reporting, Roe says, the remaining compliance plan approval was straightforward, partly because much of it had been determined in the earlier steps.
Compliance requirements are more stringent for coprocessed D3 and D6 RINs, he adds.
Two other companies expect to petition EPA in the coming year for their corn kernel fiber-to-cellulosic ethanol technologies: ICM and D3Max LLC. READ MORE