杂多酸水溶液脱除烟气中SO2新方法的研究

在孔板式吸收器（孔板孔径：50μm-70μm）中对杂酸水溶液脱除烟气中SO2的新方法进行了研究。在所考察的几种杂多酸中，H3PW12O40和H2SiW12O40对SO2的脱除率较为接近，H7PMo2W12O49和Na2HPMo12O40对SO2的脱除率相对较高，其中后者对SO2的脱除率最高。杂多酸（HPA）对SO2的脱除率随HPA浓度的提高而增高，随进气中SO2的浓度或吸收温度提高而减低。常温有利于HPA对SO2的脱除。NaCl,NH4VO3,CuSO4及H3PO4这四种添加剂均能提高HPA对SO2的脱除率。复配体系中，以上添加剂对HPA的最优配比为：NaCl/HPA:H3PO4/HPA:NH4VO3/HPA:CuSO4/HPA=1/6:1/8:1/2:1/4。进气中有NOx存在下HPA对SO2的脱除反应式，这些反应式能够很好地说明NOx的作用效果。以上结果表明：HPA水溶液具有很好的烟气脱硫应用前景。

A NEW PROCESS OF SO2 REMOVAL FROM FLUE GAS WITH AQUEOUS SOLUTIONS OF HETEROPOLY ACIDS

A preliminary investigation on a new method of flue gas desulfurization involving the use of heteropoly acids was presented. A multiorifice plate glass absorption reactor (hole diameter: 50?μm～70?μm) was used to investigate the performance of the absorbent solution. Of the heteropoly acids investigated, there is only a slight difference in SO2 removal efficiency between H3PW12O40 and H4SiW12O40, the SO2 removal efficiency of H7PMo2W12O49 and Na2HPMo12O40 appears to be higher, the performance of Na2HPMo12O40 is the best among the four. The SO2 removal efficiency of HPA increases with the increase of its concentration, decreases with the increase of the feed gas SO2 concentration and absorption temperature. Room temperature was determined to be favourable for SO2 removal. All additives including NaCl, NH4VO3, CuSO4 and H3PO4 were confirmed to have positive effect on the SO2 removal efficiency of HPA. The optimum molar ratios of additives to HPA in the multi-additive absorbent system were confirmed to be: NaCl/HPA∶H3PO4/HPA∶NH4VO3/HPA∶CuSO4/HPA=1/6∶1/8∶1/2∶1/4. In the presence of NOx in the feed gas, the SO2 removal efficiency increases markedly, and it reaches 100% when the mass concentration of NOx exceeds that of SO2.The probable reactions during desulfurization in presence of NOx were proposed, which could well illustrate the effect of NOx.