With the Flow

AURI and corn growers research improving distiller’s grains for exporting

By Dan Lemke

Waseca, Minn. — Minnesota’s 14 ethanol plants process about 152 million bushels of corn into 400 million gallons of ethanol each year. But liquid fuel isn’t the plants’ only value-added product.

Each bushel of corn, processed into ethanol, also yields 18 pounds of distiller’s dried grains, according to the National Corn Growers Association. DDGs primary market in Minnesota is the livestock industry. But with about 1.1 million tons a year, ethanol plants have to look beyond state borders for DDG markets.

However, the challenge to exporting DDGs is they don’t flow well after transport. Traveling long distances by rail car or trucks can compact the product so tightly that it is difficult to unload — a serious drawback for potential buyers.

AURI and the Minnesota Corn Growers are undertaking research to solve the problem. “Ethanol plants are looking to expand markets for the DDGs, but one negative right now is the flowability,” says Alan Doering, AURI technical services specialist in Waseca.

AURI will do analytical tests on distiller’s grains and evaluate moisture, fat, sugar and oil content — factors that affect flowability. Some tests will use DDGs as they are currently produced. Others will use altered samples to evaluate how certain production changes impact flowability.

An engineering firm specializing in bulk material handling will evaluate how DDGs perform under various handling conditions and look at product cohesion, temperature, compaction and how storage time affects product flow.

“We’re hoping to develop a baseline of information that can be used by ethanol plants, feed manufacturers and anyone else in Minnesota that deals with DDGs,” Doering says.

“This project is looking at ways to improve flowability in such a way that it would be relatively easy for an operating plant to adapt what we’ve learned.”

Doering expects the information to be available later this summer.