【摘要】 采用汞渗透管产生的汞蒸气和其它主要烟气成分,在小型多功能固定床试验台上开展静电除尘器(ESP)飞灰和布袋除尘器(FF)飞灰脱除单质汞的试验研究。结果表明:O2、SO2、NO对Hg0的氧化均有一定的作用,尤其SO2对Hg0的氧化效果最为显著。飞灰对汞的吸附与飞灰中Fe2O3、Al2O3等化学成分的催化氧化有一定的相关性。烟气中汞氧化率越高,飞灰中汞脱除率就越高。飞灰的孔分布越宽,越有利于对汞的吸附;微孔越发达,孔隙率越大且微孔表面利用率越高,越有利于汞的吸附。总体来说,2种ESP飞灰的汞脱除率明显高于FF飞灰的汞脱除率,飞灰的残碳量对汞的脱除起重要作用。更多还原

【Abstract】 The experimental study of elemental mercury(Hg0) removal by fabric filter(FF) and electrostatic precipitators(ESP) fly ashes was conducted by using a bench-scale multi-functional fixed-bed apparatus.A simulated flue gas was prepared by mixing heated,nitrogen gas streams containing mercury vapors(by an elemental mercury diffusion tube) and other main compositions of flue gas.The results showed that O2,SO2 and NO had a relative effect on Hg0 oxidation respectively,and especially the effect of SO2 was the most significant.Adsorption of vapor-phase elemental mercury by fly ashes was correlated with catalytic oxidation by chemical constituents such as iron oxide and alumina and so on.The efficiency of mercury adsorption by fly ashes increased with increasing that of mercury oxidation in flue gas.Wider pore distribution of fly ashes was beneficial to mercury adsorption.Developed pores with high surface utilization rate could adsorb more mercury.On the whole,the efficiency of mercury by the two kinds of electrostatic precipitator(ESP) fly ashes was significantly higher than that of fabric filter(FF) fly ashes,because the residual carbon content of fly ashes played a major role in mercury adsorption.更多还原