Optimization of the regeneration procedure for granular activated carbon

Laboratory scale experiments were conducted on the regeneration of activated carbons spent in tertiary treatment of wastewater. Wet spent carbon being regenerated thermally undergoes three regeneration stages: drying at about 220°F; Pyrolysis of the adsorbed pollutants at 500 to 1550°F; and Activation with flue gas and steam at 1600 to 1700°F. Data indicated that alkaline and iron oxide ash accumulation catalyze the oxidation of carbon pores. Leaching with HCl was found to remove the metallic elements and allow regeneration to proceed with less destruction of the carbon. Other observations are discussed.