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Pharmaceutical plants coat tablets with either a water-based or organic-based material in a batch operation that uses rotating open-ended pans. After being coated, the tablets are dried by hot air. Most tablets are coated with sugar, methyl cellulose, or ethyl cellulose. Because sugar coatings are water-based, they are not a source of volatile organic compound (VOC) emissions. Cellulose coatings can be applied either in water or in an organic media. An organic solvent is used if faster drying is required or if the tablet is sensitive to water and/or heat. This process is often referred to as film coating. The most practical VOC emission control method is adsorption of the VOC stream onto activated carbon. The pharmaceutical industry currently uses this method to control VOC emissions from tablet coating operations. Carbon adsorbers are rugged and simple to operate, and the recovered methylene chloride or chloroform is suitable for reuse without further treatment. Ethanol and isopropanol are recovered in dilute aqueous solutions that can be processed in the plant wastewater treatment facility. Incineration and refrigeration control methods are technically feasible, but uneconomic.