Skip to main content
ARS Home » Plains Area » Brookings, South Dakota » Integrated Cropping Systems Research » Research » Publications at this Location » Publication #228763
Title: Flowability Properties of Commercial Distillers Dried Grains with Solubles (DDGS)

Author
item BHADRA, RUMELA - SOUTH DAKOTA STATE UNIV
item Rosentrater, Kurt
item MUTHUKUMARAPPAN, K - SOUTH DAKOTA STATE UNIV

Submitted to: Cereal Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/18/2008
Publication Date: 4/1/2009
Citation: Bhadra, R., Rosentrater, K.A., Muthukumarappan, K. 2009. Flowability Properties of Commercial Distillers Dried Grains with Solubles (DDGS). Cereal Chemistry. 86(2): 170-180.

Interpretive Summary: Distillers dried grains with solubles, commonly known as DDGS, is the primary coproduct from corn-based fuel ethanol production. It is almost exclusively used as livestock feed, primarily beef and dairy, but swine and poultry markets are growing as well. Much of the DDGS is transported via rail out of the corn belt to livestock operations around the US. But, flowability of DDGS out of railcars is often hindered due particle bridging and jamming. Shipping and handling of DDGS has thus become a major issue to the livestock and ethanol industries alike. The objective of this investigation was to measure flowability characteristics of DDGS samples collected from five commercial fuel ethanol plants in the north central region of the US. Carr and Jenike tests were performed, and the resulting data were compared to a previously developed mathematical model. The largest particles had an average mean diameter of 1.19 mm; while the lowest particle size had an average 0.5 mm. Soluble solid levels were found to range from approximately 10.5 to 14.8%. The effective angle of friction ranged from 43.0 to 57.0°. Overall, flowability analysis of these samples indicated that the commercial DDGS samples did have the potential for flow problems, although no samples exhibited complete bridging. Quantifying flowability is a necessary step toward overcoming this logistical challenge to the utilization of DDGS.

Technical Abstract: Distillers dried grains with solubles (DDGS), the major coproduct from the corn-based fuel ethanol industry, is primarily used as livestock feed. Due to high protein, fiber, and energy contents, there is a high demand for DDGS. Flowability of DDGS is often hindered due the phenomenon of “caking”. Shipping and handling of DDGS has thus become a major issue due to bridge formation between the DDGS particles. The objective of this investigation was to measure flowability characteristics of DDGS samples from five ethanol plants in the north central region of the U.S. Carr and Jenike tests were performed, and the resulting data were mathematically compared to a previously developed empirical model. The largest particles had an average geometric mean diameter (GMD) of 1.19 mm; while the lowest particle size had an average GMD of 0.5 mm. Soluble solid levels were found to range from approximately 10.5 to 14.8% (db). The effective angle of friction (d) ranged from 43.00° to 57.00°. Overall flowability assessment indicated that the commercial DDGS samples did have the potential for flow problems, although no samples exhibited complete bridging. Quantifying DDGS flowability is a necessary step toward overcoming this logistical challenge facing the fuel ethanol industry.