Page Banner

United States Department of Agriculture

Agricultural Research Service

Title: Modeling the Energy Requirements of First-Break Grinding

Authors
item Pasikatan, Melchor - FORMERLY USDA GMPRC ARS
item Milliken, George - KS STATE UNIVERSITY
item Steele, James - FORMERLY USDA GMPRC ARS
item Haque, Ekramul - KS STATE UNIVERSITY
item Spillman, Charles - KS STATE UNIVERSITY

Submitted to: Transactions of the ASAE
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: February 1, 2001
Publication Date: August 1, 2001
Citation: Pasikatan, M. C., G. A. Milliken, J. L. Steele, E. Haque, and C. K. Spillman. 2001. Modeling the energy requirements of first-break grinding. Trans. of the ASAE 44(6): 1737-1744.

Interpretive Summary: We studied the influence of single kernel properties of wheat (mean and standard deviation of hardness, size, and mass), as measured by the Single Kernel Characterization System, and roller mill's roll gap on the energy requirements of first-break grinding. Energy requirements were measured in terms of energy per unit mass (EM), new specific surface area (ANSS, in log scale), and specific energy (EA = EM /ANSS). Wheat from six classes, previously measured for single kernel properties, were ground at five roll gaps. Energy for grinding each wheat sample was measured using the data acquisition system of an experimental roller mill. Relationships between the measures of energy and single kernel properties and roll gap were developed using statistical models. Wheat class was used as a classification variable. Roll gap and single kernel hardness had the greatest influence on EM, ANSS, and EA. Milling ratio, a variable that combined single kernel size and roll gap, reduced some competing relationships among single kernel properties and isolated the effect of single kernel mass from that of single kernel size. The effect of single kernel mass became significant in the models based on milling ratio. The models performed well in estimating EM, ANSS, and EA from a set of 100 independently ground wheat samples. The EA model is a potential alternative to break release as a basis for online roll gap control.

Technical Abstract: The influence of roller mill gap and single kernel properties of wheat on the energy requirements of first-break grinding was studied. Multiple linear regression models for energy per unit mass (EM), new specific surface area (ANSS, in log scale), and specific energy (EA = EM /ANSS) were developed based on milling data from six wheat classes ground at five roll gaps with an experimental roller mill. The models, which were functions of roll gap, single kernel properties, and wheat class as a classification variable, explained most of the variability in the experimental data. Roll gap and single kernel hardness had the greatest influence on EM, ANSS, and EA. Milling ratio, a variable that combined single kernel size and roll gap, reduced some collinearities among single kernel properties and isolated the effect of single kernel mass from that of single kernel size. The effect of single kernel mass became significant in the models based on milling ratio. Good agreement between predicted and measured values was observed from 100 validation samples. The EA model is a potential alternative to break release as a basis for online roll gap control.

Last Modified: 7/25/2014
Footer Content Back to Top of Page