which removes excess moisture. The cylinder cleaner uses six or seven rotating, spiked cylinders to break up large clumps of cotton. Finer foreign material, such as soil and leaves, passes through rods or screens for removal. The stick machine uses centrifugal force to remove larger foreign matter, such as sticks and burrs, while the cotton is held by rapidly rotating saw cylinders. The gin stand uses the teeth of rotating saws to pull the cotton through a series of "ginning ribs", which pull the fibers from the seeds which are too large to pass through the ribs. The cleaned seed is then removed from the gin via an auger conveyor system. The seed is reused for planting or is sent to an oil mill to be further processed into cottonseed oil and cottonseed meal. The lint cleaners again use saws and grid bars, this time to separate immature seeds and any remaining foreign matter from the fibers. The bale press then compresses the cotton into bales for storage and shipping. Modern gins can process up to of cotton per hour. Modern cotton gins create a substantial amount of cotton gin residue (CGR) consisting of sticks, leaves, dirt, immature bolls, and cottonseed. Research is currently under way to investigate the use of this waste in producing ethanol. Due to fluctuations in the chemical composition in processing, there is difficulty in creating a consistent ethanol process, but there is potential to further maximize the utilization of waste in the cotton production. See also Prattville Gin Factory Cotton bale References Notes Bibliography External links Overview of a Cotton Gin – USDA site The Story of Cotton – National Cotton Council of America site National Cotton Ginners Association US Cotton Gin Industry – EH.Net Encyclopedia of Economic History Invention of Cotton Gin – eHistory.com Cotton: the fiber of life – includes a schematic diagram illustrating the seed removal process Video of manual cotton gin in operation via YouTube 1769 introductions Agricultural machinery American inventions Cotton production Indian inventions Slavery in the United States Textile machinery Ancient inventions