Technical development and sociological analysis for a higher cotton fibre quality in ginning

This thesis addresses the issue of shortened cotton fibres during ginning, which hampers mechanical recycling and reduces overall recycling rates. Long and strong fibres are crucial for multiple recycling cycles. Otherwise, short fibres lead to waste. The ginning process faces challenges such as poor machine settings, wrong moisture management in processing, storage in dusty surroundings and a lack of practical knowledge among workers. The hypothesis posits that better moisture management and structured knowledge transfer (e. g. in a Train the Trainer program) can help reduce fibre length losses in ginning. The research combines literature reviews, expert interviews and on-site investigations in India and Egypt with lab developments at RWTH Aachen University. It focuses on reliable moisture measurement techniques to preserve fibre length. Direct methods like the oven standard are accurate but slow, while indirect methods, including near-infrared spectroscopy (NIR) and electrical resistance measurement, offer quicker alternatives. Resistance measurement proves most viable for on-line control due to its low cost and robustness. Therefore, this system is further developed and used as a 50 cheap approach for ginner trusted operation. Additional moisturisation system enable fibre gentle processing. Operationally, maintaining optimal moisture levels is critical. Peak fibre strength occurs at around 15% moisture content, while storage above 12% risks quality degradation. The study emphasizes the importance of effective training for ginning mill operators regarding moisture control and machine maintenance. From an economic perspective, bale pricing is sensitive to quality differences. Quality preservation better preserves prices than increases above standard traded qualities. Implementing a moisture-management system can yield significant financial returns by preserving fibre quality. A cooperative model like Raiffeisen or farmer cooperatives as used in the USA involving farmers as co-owners of ginning mills can enhance focus on premium cotton attributes while fostering continuous improvement through reinvestment in training. Overall, this thesis advocates for simple yet robust measurement tools combined with effective operator training strategies to improve cotton quality sustainably while enhancing economic viability in production environments.