Most of the cotton ginning operations is performed by using double roller (DR) ginning machines which serve an important role in the ginning industries. The rollers used in these industries are made of Chrome Composite Leather- Clads (CCLC) covering fixed to a shaft. The CCLC coverings contain about 18 077 to 30 783 mg/kg (ppm) of chromium particles which is a carcinogenic substance. When the seed-cotton is processed in DR ginning machine, the lint cotton is contaminated with chromium dust of about 110 to 1990 ppm as total chromium, against the safe limits of 0.1 ppm. During the cotton ginning process, due to persistent rubbing of leather over stationery knife, the chromium particles are carried into lint cotton in such a way that the spun yarns contain about 100 to 200 ppm, which according to eco-standards for spun yarns should not be more than 0.1 ppm. The CCLC rollers used in cotton roller ginning machines get powdered during the ginning process as chromium specific dust. Gin and mill workers are directly exposed to this carcinogenic substance and are vulnerable to health hazards. Chromium leak threat to health effects to those who wear cotton[46]. To offset this problem, eco-friendly rubberized cotton fabric (RCF) washers / rollers both for laboratory and commercial studies have been fabricated and experimented [36]. These eco-friendly chrome-less rollers were evaluated for their performances, with a particular reference to techno-commercial and environmental aspects. In this the roller covering is made of multiple layers of fabrics bonded together using white rubber compounding which has a surface finish conducive to high ginning efficiency. On the basis of the design and development of various rollers with subsequent performance evaluation studies, eco-friendly RCF washers/rollers have been demonstrated with a reference to techno-commercial and eco-friendliness in ginneries. These newly developed RCF rollers were successful in their operation. These were found more effective and efficient than CCLC roller ginneries. They eliminated chromium related contamination and pollution problems. This cleaner technology is a source-at-control preventive measure such that the cotton ginning and textile industries meet the requirements of environmental standards being enforced by many countries and high quality yarns and fabrics meeting international standards are produced. These ginneries have been tested commercially. This was found to be better in all aspects with reference to cotton technological properties, dye-catch properties and physical and chemical properties of CCLC rollers. It could be used commercially as an alternative in the cotton roller ginning industries for the benefit of the environment, textile and gin mill owners, traders, workers, employees of the Government and ultimately the society.
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