Tracking Seed Coat Fragments in Cotton Ginning

Abstract

Seed coat fragments (SCF) in lint cause problems in textile mills during spinning and dyeing, so it is important to prevent or remove them during ginning. The objective of this experiment was to quantify SCF as they were formed and removed during ginning so that future studies can focus on preventing SCF formation. Samples of cotton, seed, and trash were collected throughout a gin to analyze SCF, motes, seed meats, and seed. The lint cleaner did not change the number of SCF in lint, but it reduced the weight of SCF by 56% as it removed larger SCF or broke them into smaller SCF. Seed meats in the ginned seed and small seed missing after the gin stand were estimated to be 0.8% and 2.3%, respectively, of all seed ginned, accounting for 32% and 15% of SCF formed in the gin stand, so a significant portion of SCF was attributed to seed damage not revealed by simply observing damaged seed in the seed roll. Damaged seed observed in the seed roll was 7% higher than in seed cotton, and these were thought to be a major source of SCF found in lint. The SCF mass entering the gin stand was 24% of the SCF mass exiting the gin stand, so a small but significant portion of SCF were formed before the gin stand. Seed meats found in the seed cotton cleaner waste were estimated to account for 22% of SCF found entering the gin stand. Seed damage occurred in the field, in seed cotton cleaners, and in the gin stand, so there are opportunities at each of these steps to prevent SCF in lint.