| China was the largest coal-produced and coal-consumed country in the world, and also regarded coal as principle in primary energy source production and consumption structure. The combustion of coal in massive amounts had led to a great heavy air pollution mainly due to emission of SO2 and NOx. The damage and lose from acid rain caused by SO2 and NOx had severely baffled sustainable economic development of our country. Therefore, the cut down of SO2 and NOx emissions, the control of air pollutions and the protection of atmosphere environmental quality was one of the most important environmental protection problems at present or in the future long time.The study on developing a kind of technology in desulfurization and denitrification which has Chinese characteristics had great significance.The molding of semi-coke can effectively decrease the pressure decending of catalyst bed and the operation cost of reactor. Semi-coke from Zhalainuoer of Inner Mongolia was selected in this experiment. Research was done in the molding of semicoke.There were following steps in the molding of semi-coke: Firstly, crushing the semi-coke into 100 meshes, then water-washing to neutral and drying after being actived with HNO3. Secondly, uniformly mixing the treated active semi-coke powder and additive in a certain proportion, adding appropriate quantity of adhesive and extruding catalyst by molding device. Thirdly, calcining the semi-coke in existence of water, oxygen at high temperature of 700℃. The proportion of catalyst with the best mechanical properties was: semi-coke actived with HNO3 80%, coal tar 15%, starch 1%, kaoline 1.5～2%, polyethylene glycol 1%, V2O5 1%, graphite 0～0.5%.The results of surface functional groups of alkaline and acid test indicated that: the surface of raw semi-coke was alkaline; the acidic functional groups on the surface of semicoke were greatly increased after semicoke being actived with HNO3, while the alkaline functional groups greatly decreased, the surface of semicoke is acidic. Calcination could rearrange the functional groups that on the surface of semicoke, and make acidic functional groups decompose into alkaline functional groups. The content of alkaline functional groups increased while acidic functional groups decreased.It had a better effect that calcining the semicoke in existence of vapor and O2.The net base amount is 10 times higher than that of raw semicoke.The content of both base functional groups and acidic functional groups on semi-cokes loaded with V2O5 increased, but the net base amount was less.The evaluation of desulfurization activity of catalyst prepared in different methods shown that: the activity increased after the semi-cokes loaded with V2O5, thus we can infer that the surface base was not the only fact which determined the activity of semi-coke.The preparation of molding structured semi-coke catalyst used the way that molding firstly and then calcining the semi-coke in existence of water, oxygen at high temperature of 700℃. The desulfurization activity of catalyst could be greatly increased by calcining. Sulfur capacity increased up to 25% than calcining only in the protection of N2. The catalyst which used coal tar as adhesive and with the particle diameter ofφ3mm had higher desulfurization activity.The fixed-bed reactor was applied to evaluate the following parameter which affected the activity of the catalyst: reaction temperature, space velocity, and the content of H2O and O2 etc. The results of experiments indicated that: both reaction temperature and space velocity had great influence to the desulphurization activity of semi-coke. The optimum temperature was in the range of 60℃～80℃and the optimum space velocity was 600h-1.The existence of O2 in flue gases could enhance the desulphurization activity of semi-coke, the optimum content of O2 was 5%. The overall of O2 could not only enhance the desulphurization activity, but also bring competitive adsorption of O2 and SO2. Appropriate content of H2O in flue gases was absolutely necessary for desulphurization reaction. The optimum water content was 8% for the molding structured semi-coke catalyst.The denitrification activity of molding structured semi-coke catalyst was also evaluated.The results of experiments indicated that: calcining the semi-coke in existence of water, oxygen at high temperature and loading V2O5 on semi-coke could not only improve the desulphurization activity, but also improve the denitrification activity of molding structured semi-coke catalyst. Temperature influenced the denitrification activity most. We could see from the experimental results that the denitrification activity decreased with the temperature increasing. The optimum temperature suitablele for denitrification was in the range of 60℃～80℃. Operational space velocity was selected from 800h-1 to 1000h-1. The existence of O2 in flue gases could enhance the denitrification activity of catalyst, it had the best effect when the content of O2 was in the range of 10%～14%. H2O in flue gases had poisoning effect on the molding structured semi-coke catalyst. Thus the existence of H2O should be avoid in the denitrification operation.
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