A Straighter, Shorter Pathway

Confidence builds in overcoming the hurdles slowing corn kernel fiber-to-cellulosic ethanol approvals.
By Sue Retka Schill | March 03, 2018

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 EPA finalized the rule to implement the RFS in 2010. The following year, QCCP began working with EPA on the corn kernel fiber clarification and Edeniq filed its petition. Thome says the delay was partially a result of others approaching EPA with feedstock questions in 2012. “EPA said, ‘Hang on, time out. We’re going through a formal and full rulemaking process around what feedstocks qualify.’”

In mid-2014, EPA came out with its rule that defined corn kernel fiber as a crop residue, clearing the way for QCCP and Edeniq customers’ registrations. It also established the rules for cellulosic biofuel from biogas, discussed other issues with crop residue feedstocks and made corrections and modifications to the 2010 rule. On its page of approved pathways, Edeniq’s Pathway approval goes directly to that rule.

But it was QCCP that was first out of the gate. Delayne Johnson, CEO, says the plant was generating D3 RINs by October 2014. Edeniq’s first Pathway licensee, Pacific Ethanol-Stockton, California, didn’t get its approval until September 2016.

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. Pacific Ethanol-Stockton was the first to implement the technology, and Thome says it was seven months from the time the plant sent its registration to EPA before it got approval to generate D3 RINs. He adds that while the Edeniq Pathway registration process appears settled, every company’s technology will need separate approval and there will be unforeseen issues that could cause delays.

LSCP’s Journey
In January 2017, Little Sioux Corn Processors became the third plant to be approved for D3 RINs under the Edeniq Pathway, but it ran into one of those unforeseen issues that took most of the year—until late November—to iron out.

LSCP was in the first batch of ethanol plants to be approved for generating D6 RINs above its grandfathered volume in EPA’s Efficient Producer Petition Process (EP3). Not only did LSCP’s EP3 approval letter specify corn starch, which needed to be amended, but the agency had to determine how to handle the coprocessed cellulosic ethanol volume in the required 365-day rolling average greenhouse gas (GHG) reduction spreadsheet. Every efficient producer plugs in the bushels of corn crushed, the gallons of ethanol produced and the energy consumed as electricity and natural gas to demonstrate a 20 percent GHG reduction relative to the baseline gasoline for all gallons above the grandfathered volume. The compliance monitoring plan that’s part of that process is quite detailed, down to the serial numbers of the equipment being used to measure ethanol production and daily corn grind.

LSCP’s approval letter for its updated petition goes into detail about EPA’s decision on how the agency plans to handle the cellulosic gallons. All the upstream lifecycle GHG emissions associated with the corn feedstock is to be used in the corn starch ethanol GHG reduction calculation, as is all the energy used in the process. The cellulosic gallons are to be subtracted from the total volume. In its updated guidance document, “How to Prepare an Efficient Producer Petition Version 1.2,” EPA says it has added a category for starch producers who coproduce cellulosic ethanol from corn kernel fiber, with the requirement that the Part 80 D3 RIN registration be completed first. The methods for measuring the volumes of cellulosic ethanol must be established in the D3 registration process before the formulas used in the EP3 spreadsheet calculating the 365-day rolling average can be properly applied, the agency explains.

LSCP 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. In early December, LSCP was preparing to redo its baseline without the cellulases, a voluntary step, he stresses. Edeniq will be back when the cellulases are reintroduced to collect the samples and run through its proprietary testing protocols. The results must also be validated by an independent engineer. EPA says that for every 500,000 gallons—or at least annually—the cellulosic lift must be recertified, Roe says. Participating in a RIN quality assurance plan also is likely to be a market requirement.

2 More on the Path
Two other companies expect to petition EPA in the coming year for their corn kernel fiber-to-cellulosic ethanol technologies: ICM and D3Max LLC.

ICM’s Gen 1.5 Grain Fiber to Cellulosic Ethanol Technology is built on its Fiber Separation Technology. Steve Hartig, ICM’s vice president for technology development, says the first installation of Gen 1.5 will be colocated with the 70 MMgy corn starch ethanol plant, trademarked as Element, under development next to ICM’s Colwich, Kansas, headquarters. Engineering and financing is nearing completion and groundbreaking is expected in early 2018.

Gen 1.5 sends the fiber stream from FST through a separate process where it is pretreated and fermented. The fiber fermentation broth is then combined back into the existing ethanol plant’s larger fermenter to complete fermentation. Hartig reports the company is working internally and with others, including the National Renewable Energy Laboratory, to develop open industry standard methods for all processes to use for cellulosic ethanol tests. “ICM thinks this is important for the credibility of this industry,” he says. “ICM will be doing test method validation and third-party engineering review during the course of 2018 and then submit for actual approval immediately after start up.”

ICM expects its approval process to move quickly. “From our discussions with the EPA, ICM believes they have made positive steps in pathway approvals and they have assured us of a speedy process,” Hartig says.

D3Max also will be going through the regulatory process this year. The company’s patented pretreatment and fermentation process for wet cake occurs in a separate reactor and fermenter.

According to Mark Yancey, D3Max’s chief technology officer, the technology’s commercial design and associated front-end loading (FEL), completed in January, defined the scope and cost of a large-scale installation. At press time, the company’s pilot testing partner, ACE Ethanol LLC, in Stanley, Wisconsin, was still analyzing the FEL and related builder estimates, while signifying in early January that a commercial-scale project was likely. With construction expected to begin this spring, Yancey expects the permit modifications to be straightforward. “The same goes for the EPA registration and quality assurance plan,” he says. “We have about a year to get that done. Other companies have blazed the trail and gotten approval, and I don’t see EPA registration being a problem.”


Author: Susanne Retka Schill
Freelance Journalist
retkaschill@yahoo.com