Metso's carbon regeneration system regenerates carbon in order to retain adsorptive properties to levels close to new fresh carbon. Features: Metso’s carbon regeneration systems utilize thermal regeneration technology. Some industries call the product “AC” for activated carbon. The process uses an indirect fired kiln to heat the activated carbon to 700°C, driving off the organic and inorganic contaminants. The system uses a recycle duct to improve energy efficiency.