Water contamination by organic compounds is an important environmental problem. Activated carbon filters are widely used to eliminate these contaminants. After exhaustion, activated carbon must be regenerated or replaced by fresh carbon. Carbon regeneration frequently is a major part of total operating cost associated with granular activated carbon (GAC) adsorption systems. Spent GAC used in water, wastewater, and other liquid phase applications, is generally reactivated using a two-step treatment (acid aqueous washing followed by thermal air treatment). High temperature thermal process allowing drying, baking, and gasification to occur. Traditional thermal regeneration has been conducted in Muffle furnace/Hearth furnace. We Have to Studied on the parameter of Particle Size Distribution, Amount of solid to be treated, Amount of Chemical to use for Pretreatment, Temperature, Time, Heating Rate. Design of experiments will be applied to optimize operating parameters.