Cotton gin fuel use patterns

Authors: Funk, Paul; Hardin Iv, Robert; Terrazas, Albert; Yeater, Kathleen

Submitted to: Transactions of the ASABE
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/3/2020
Publication Date: 7/21/2020
Citation: Funk, P.A., Hardin Iv, R.G., Terrazas, A.A., Yeater, K.M. 2020. Cotton gin fuel use patterns. Transactions of the ASABE. 63(3):645-653. https://doi.org/10.13031.
DOI: https://doi.org/10.13031

Interpretive Summary: The cost of fuel for cotton gin drying system and moisture restoration system burners has increased and currently is between 6.5% and 8.5% of the total cost of ginning. Fossil fuel costs have been volatile, with the average price for propane doubling over the past ten years, and weather-dependent drying requirements are unpredictable, combining to make drying energy the least manageable cost and greatest threat to profitability. Facility design parameters played a modest role in fuel use efficiency, with burner location proximate to material pick up being the most significant variable. Significant operating parameters were final moisture content, volumetric flow of heated air, and processing rate. Though beyond the control of gin personnel, harvest conditions played a major role in determining fuel use.

Technical Abstract: Cotton gin drying system audits were performed in 25 commercial cotton gins from California to Georgia during the 2016 and 2017 ginning seasons. Most of the 25 audited gins had multiple drying systems resulting in 76 unique drying system observations lasting about one hour each. Fuel energy use was estimated by measuring air flow and temperature change through each burner. Drying energy was estimated by measuring the seed cotton mass flow and change in moisture content. Principal component multivariate statistical analysis reduced the number of variables. Fuel use efficiency was a function of the moisture content of incoming material, the distance between the burner and the point where cotton is picked up (the mix point), and the presence of insulation on this duct. Gin operators can save energy by avoiding unnecessary drying, minimizing the volume of conveying air, and keeping the gin operating at its maximum processing rate while avoiding down time. Growers can contribute to more economical operation by harvesting cotton once it is dry and storing modules so they don’t get wet.