Impacts of Gin and Mill Cleaning on Medium-Long Staple Stripper-Harvested Cotton

Abstract

The quality of upland cotton grown in the Texas Plains, which in good seasons constitutes nearly 40% of all U.S. cotton, has changed radically over the past decade. However, production practices, particularly pertaining to harvesting and ginning, remain largely unchanged, with a predominately stripper-harvested crop. Hence, the necessity to subject the lint to vigorous cleaning at the gin could adversely impact the use value of the cotton in high-value added applications more typically served by picker-harvested cotton. This research was conducted to provide a systemic analysis, combining perspectives from both the gin and the spinning mill, of the impacts of mechanical cleaning on the emerging stripper-harvested cotton with improved fiber properties that appear suitable for ring-spinning. Five cotton varieties grown over three seasons were processed through various sequences of gin and spinning mill cleaning processes. Analysis of the properties of individual fibers across the gin and spinning mill processing chain revealed significant interactions impacting fiber entanglements (neps), mean length, and short fiber content. Both neps and length distribution parameters appeared significantly impacted by fiber damage in both the ginning and spinning processes. However, the damage inflicted through both ginning and spinning may be a function of only fiber maturity. Mature cottons have lower fiber damage potential and appear to be less affected by the processes of lint cleaning and spinning preparation than immature cottons. The latter have higher fiber damage potential, which is reached even with minimal cleaning at the gin because if those immature fibers are preserved at the gin, they will ultimately break in spinning preparation.