New enzymes for corn ethanol

By Luke Geiver | July 15, 2010
From the same amount of starch, plants can now produce more ethanol, to the credit of major enzyme producers Genencor and Novozymes. At the 2010 International Fuel Ethanol Workshop & Expo, Genencor officially released its trademarked Spezyme Robust Starch Liquefaction enzyme. Novozymes also announced its new product, the Spirizyme Excel enzyme.

The Spezyme RSL, the result of a three year controlled experiment and testing period, more efficiently liquefies dry ground corn or milo. Because the product can work across a wide range of pH levels with a greater thermal stability, Hans Foerster, director of marketing for Grain Processing Americas for Genencor, said the Spezyme provides a wider range of use. "We aimed for a design that would help this enzyme work in the overwhelming majority of plants," Foerster said. The initial research was geared toward producer needs, and the result is an enzyme that requires only one dosing and no pH adjustment. "The industry has struggled with this for many years at plants using a hydro heater or jet. We focused on improving both the thermal element and the pH balance," said Foerster.

Due to the robust nature of the enzyme, producers can run their systems without accounting for the frailty typically associated with enzyme use. Using the enzyme in a plant only requires two changes: moving the enzyme dosing up front and reducing pH adjustments which permits removing ammonias and the sulfuric acid used to control pH levels. Currently, 20 different ethanol facilities are using the Spezyme RSL, and each can expect to see a 25 to 50 percent reduction in sulfuric acid usage.

The Spirizyme Excel, the new Novozymes product, works to break down the most difficult starch fractions in the feedstock to maximize production yields, according to the company. The enzyme can increase yields by more than one percent, enough to provide an added $1 million or more revenue for an ethanol plant each year. "Novozymes is at the forefront of developing technologies that allow biofuel producers to make more from less," said Poul Ruben Andersen, global biofuel marketing director. "Novozymes has achieved great breakthroughs in cellulosic biofuel recently, but this does not mean we have forgotten about corn ethanol."

The enzyme producer hasn't forgotten about China either. Cofco, a leading Chinese producer and supplier of processed agricultural products, and Sinopec, the world's third largest oil refiner out of China, have both partnered with Novozymes. Through a memorandum of understanding, the three companies will work to make commercialization of cellulosic ethanol in China a reality. Cofco and Sinopec are on track to complete a 3 MMgy corn stover-based plant in the third quarter of 2011. Novozymes will supply the enzymes.

Cofco and Novozymes have also partnered with a U.S. company at the Purdue Research Park in West Lafayette, Ind. Formed by Nancy W.Y. Ho, Green Tech America Inc. will provide its yeast-based cellulosic technology. The Saccharomyces yeast from GTA doesn't use toxic or expensive chemicals such as antibiotics to maintain the plasmids containing the cloned genes in the yeast, she explained. "For GTA to sign a license agreement with two giant companies in the world, it means they will use (our) yeast in their production of cellulosic ethanol," said Ho. ADM and Iogen have also tested the yeast.

Outside of enzyme production and yeast development, Novozymes has also partnered with Ceres Inc., an energy crop company, to co-develop customized plant varieties and enzyme cocktails. The two hope to improve biomass conversion to fuel while lowering capital and operating costs. "I envision a day when we can approach conversion facilities and their feedstock suppliers with a complete package of tailored seed varieties and enzymes as well as crop management and processing recommendations," said Spencer Swayze, senior manager of business development at Ceres. "Relatively small percentage changes in efficiency can result in substantial process savings and lower capital and operating costs."

For the immediate future, both Novozymes and Genencor are helping producers improve efficiency and yields, and it doesn't appear as if that will be changing anytime soon. "We see a bright future in grain based alternative energy solutions," said Troy Wilson, vice president of grain processing for Genencor. "We have invested millions of dollars as seen in the last two or three years, and, we will continue to invest."