Measurement of Rheology of Distiller’s Grain Slurries Using a Helical Impeller Viscometer

Abstract

Abstract2Auburn University, Office of the Provost, Auburn, AL 36849, Current research is focused on developing a process to convert the cellulose and hemicellulose in distiller's grains into fermentable sugars, increasing both ethanol yield and the amount of protein in the remaining solid product. The rheologic properties of distiller's grain slurries were determined for concentrations of 21,23, and 25%. Distiller's grain slurries are nonNewtonian, heterogeneous fluids subject to particle settling. Traditional methods of viscosity measurement, such as cone-and-plate and concentric cylinder viscometers, are not adequate for these fluids. A helical impeller viscometer was employed to measure impeller torque over a range of rotational speeds. Newtonian and non-Newtonian calibration fluids were utilized to obtain constants that relate shear stresses and shear rates to the experimental data. The Newtonian impeller constant, c, was 151; the nonNewtonian shear rate constant, k, was 10.30. Regression analysis of experimental data was utilized for comparison to power law, Herschel-Bulkley, and Casson viscosity models with regression coefficients exceeding 0.99 in all cases.

Rheological Properties of Conde Nsed Corn Distillers Solubles

“…[3] przedstawili zależność lepkości od temperatury i prędkości obrotowej wrzeciona w odniesieniu do wywaru gorzelnianego uzyskanego podczas fermentacji alkoholu etylowego z melasy trzciny cukrowej. Houchin i Hanley [9] przeprowadzili natomiast badania zatężonych zawiesin wywarów gorzelnianych (21 i 25 %) przy użyciu wiskozymetru zaopatrzonego w mieszadło wstęgowe. Autorzy ci stwierdzili, że w zależności od stężenia zawiesiny do opisu krzywych płynięcia można zastosować model potęgowy Ostwalda de Waele'a lub model Cassona.…”