| The activated coke desulphurization process is an advanced dry desulphurization technology. This process has several excellent features, including high desulphurization efficiency, no water consumption, no waste water, no waste residue, and obtaining high concentration SO2 from desorption, which could be used to produce sulfuric acid, sulfur, liquid SO2, chemical fertilizer and so on. At present, in our country this technology is only at the pilot test stage, which does not have large-scale industrial application. Therefore, the activated coke desulphurization technology has good development prospect in our country.The influence of activated coke diameter, fixed-bed reactor temperature, SO2, O2 and water vapor concentration to the desulphurization efficiency was systematically studied with activated coke which produced by Ningxia coal group. The experiment was carried out in the self-made tubular reactor. The results indicated when the activated coke diameter was between 60 mesh and 80 mesh, and the flow velocity of simulated flue gas was more than 2m/min, the effect of intraparticle and external diffusion could be eliminated. When SO2 concentration was 3000×10-6, reactor temperature was 80℃, O2 concentration was 20%, and water vapor concentration was 12%, the sulfur capacity reached the best value, and the desulphurization efficiency was above 97%. But considering the actual condition of power plants, the reactor temperature was 120℃, the O2 concentration was 8% in the following experiments.The influence of desorption temperature and time to SO2, fluorine and chlorine desorption was studied in desorption-regeneration experiment. The results indicated the desorption efficiency of SO2, fluorine and chlorine was 50%, 0.22% and 0.12% respectively, and the desorption quantity of SO2, fluorine and chlorine increased along with desorption time, when desorption temperature was 370℃.The effect of adsorption-desorption cycle numbers to the desulphurization efficiency and sulfur capacity was studied in the circulation experiments. The results indicated the sulfur capacity of the second adsorption reached maximum value in five cycle experiments, then sulfur capacity reduced along with cycle index increased; and the desulphurization efficiency could still maintain about 96% after five circulation.The influence of activated coke surface properties to the desulphurization efficiency was studied with SEM and FTIR. The results indicated the pore structure of desorption sample was so obvious and neat that it was easy to adsorb more SO2, and many kinds of oxygen-containing functional groups on activated coke surface affected adsorption and desorption reaction.The adsorption dynamic equation and the adsorption model were established. The simulated desulphurization efficiency curve and the experimental value curve were similar, so the model could provide some reference for the practical application.
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