Abstract:
Activated coke (AC) supported V2O5 (V2O5/AC) is very effective for simultaneous removal of SO2 and NO from flue gas at around 200℃. The SO2 removal is accomplished by oxidation of SO2 into SO3 and then formation of sulfuric acid storing within the pores of AC. Regeneration of the used V2O5/AC is important for continuous operation. It can be achieved in the presence of NH3 at temperatures lower than that required by AC under an inert atmosphere. SO2 desorbed from the used V2O5/AC can be recovered to solid ammoniumsulfur salts through reactions between SO2 and NH3 upon cooling of the regeneration effluent to temperatures below 80℃. Coupling of the regeneration and the ammoniumsulfur salts formation processes by recycling the effluent gas back to the regeneration reactor make the regeneration and sulfur recovery very efficient. This work studies the effect of regeneration conditions on desorption of SO2, recovery of sulfur, and SO2 and NO removal activities in the subsequent operation. Regeneration conditions tested include the amounts of NH3 been injected, regeneration temperature, regeneration time and the recycle rates of the effluent gas. The results show that the regeneration temperature and time affect the desorption of SO2 and subsequent SO2 and NO removal activities. Amounts of NH3 injected affect sulfur recovery and SO2 and NO removal activities, but recycle rate of the effluent gas has little effect on all these parameters.