Degree Type


Date of Award


Degree Name

Master of Science


Agricultural and Biosystems Engineering


Industrial and Agricultural Technology; Biorenewable Resources and Technology

First Advisor

Matthew Darr


The United States is beginning to replace petroleum-based fuels and chemicals with renewable sources to make the same products. One of the major petroleum products consumed in the United States is gasoline used in liquid fuel transportation. Currently, corn grain-based ethanol is the primary leader in renewable fuels, but cannot completely replace gasoline for many reasons. Therefore, cellulosic biofuels, renewable fuels derived from the cellulose in plants, have become of significant interest, due to the large quantity of cellulose on Earth.

The primary crop in Iowa is currently corn, and will likely stay that way for years to come. The infrastructure in Iowa is built around corn and soybean production, and therefore it will be very difficult to introduce a new crop for energy. Corn stover, however, is becoming more abundant as corn yields climb, and can be used to produce cellulosic biofuel. However, since corn stover has never before been harvested on a commercial scale, its material properties, and sampling techniques to measure those properties, are not well established. The four technical chapters in this thesis help to define some of corn stover's material properties, and to establish appropriate sampling techniques for these properties. The first chapter begins by assessing two different types of rapid moisture analyzing methods, as well as exploring how to obtain an accurate and representative subsample for other potential rapid analyzers. The methods developed and validated in this chapter will help to allow material properties to be measured on an industrial, large-scale corn stover harvest. The second technical chapter evaluates two sample sizes to determine the proper sample size to accurately analyze material properties of corn stover bales. This chapter outlines some guiding principles to obtain representative samples within corn stover bales. The third technical chapter examines the individual bale's variability for its material properties, moisture content and ash content. Finally, the fourth technical chapter builds on the variability of corn stover by exploring variability of moisture and ash content within a set of bales harvested from the same field. These variability chapters can aid future corn stover processing facilities in determining the number and location of samples to be taken from bales, as they're being harvested.


Copyright Owner

Brittany Nicole Schon



File Format


File Size

123 pages