|Boykin Jr, James|
Submitted to: Transactions of the ASABE
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/20/2009
Publication Date: 4/29/2009
Citation: Boykin Jr, J.C., Armijo, C.B., Whitelock, D.P., Buser, M.D., Holt, G.A., Valco, T.D., Findley, D.S., Barnes, E.M., Watson, M.D. 2009. Fractionation of Foreign Matter in Ginned Lint Before and After Lint Cleaning. Transactions of the ASABE. Vol. 52(2): 419-426. Interpretive Summary: In 2007, there were 17 million bales of cotton harvested in the U.S. of which nearly 13 million were expected to be exported. The quality of the cotton fibers is important to both domestic and foreign consumers, but foreign consumers typically demand higher grade cotton that’s cleaner with higher quality fiber. Saw-type lint cleaners are used in cotton gins to remove foreign matter and improve the grade of cotton lint, but these machines also damage fibers. The overall goal of this project was to improve the grade of cotton with less fiber damage. The first step was to survey commercial cotton gins to characterize foreign matter found in lint before and after lint cleaning. Nine commercial gins across the cotton belt were visited twice to collect lint samples. Results showed that 81% of the trash found in lint before cleaning was leaf, seed coat fragments, and sticks, and that seed coat fragments and sticks were at times more difficult to remove by lint cleaners. The conclusion drawn from this study was that efforts to improve lint cleaning needed to more specifically target the removal of leaf, seed coat fragments, and sticks from lint.
Technical Abstract: One goal of lint cleaning at a cotton gin is to reduce the non-lint material to an acceptable level with minimal fiber damage. In an effort to improve lint cleaner performance, an initial study was conducted on lint collected before and after lint cleaning at 9 commercial gins across the cotton belt to characterize non-lint content. Samples from this study were first processed with a MDTA-3 (Micro Dust and Trash Analyzer 3, SDL Atlas, Stockport, England) to determine trash, fiber fragment, and dust content. The trash portion was retained for additional manual fractionation to determine the percent of material classified as seed coat fragments (SCF), motes, funiculi, sticks, leaf, bark, lint, and “other” material. Leaf, SCF, and sticks were the largest fractions accounting for 81% of the total trash sample. Overall, total trash decreased by 57% due to lint cleaning, and trash fractions remained consistent in samples before and after lint cleaning. Lint cleaning efficiency in terms of SCF was less than the overall cleaning efficiency, and lint cleaning efficiency for bark, mote, and other (all minor components) was higher than the overall cleaning efficiency. The lint cleaning efficiency for SCF was increased significantly when higher SCF levels were found before the lint cleaner, but this trend was not found for other fractions. Results of this experiment will help direct future studies to improve lint cleaning.