水蒸气对金属铁与丙烯还原NO的影响

Effect of water vapor on NO reduction by iron with propene

实验研究了水蒸气对丙烯在金属铁作用下还原NO的影响。研究了陶瓷管流动反应器在300~1 100℃时不同条件下水蒸气对脱硝效率的影响,采用XRD对反应后铁样品表面的组分进行分析。结果表明,在N_2氛围条件下,水蒸气使NO的还原效率有所降低。在模拟烟气条件下,水蒸气使NO的还原效率增加,如ξ1=0.9,在1 000℃时,烟气中含有体积分数为7.00%的水蒸气时,NO的还原效率为93.0%,而无水蒸气时NO的还原效率为85.5%。在湿烟气条件SO_2对丙烯在金属铁表面还原NO的效率影响不大,可以忽略。在N_2氛围,有水蒸气时,丙烷在金属铁表面还原NO的效率高于丙烯。但在模拟烟气条件下,有水蒸气时,丙烯在富燃料条件下在金属铁表面还原NO的效率高于丙烷,在富氧条件下则相反。

The effect of water vapor on NO reduction by propene with iron was experimentally studied.NO reduction efficiency at different conditions was tested in a ceramic tube flow reactor at 300-1 100℃ when there was water vapor.XRD was used to analyze the composition of the iron samples after reaction.Results showed that,in N2 atmosphere,NO reduction efficiency decreased in the presence of water vapor.In simulated flue gas atmosphere,NO reduction efficiency was promoted by water vapor,e.g.,whenξ1 =0.9,NO reduction efficiency with 7% water vapor and without H2 O were93.0% and 85.5% respectively at 1 000 ℃.In wet simulated flue gas atmosphere,SO2 has a very small effect on NO reduction efficiency which could be neglected.In N2 atmosphere,when there was water vapor,NO reduction efficiency by C3H8 over iron was higher than that by C3H6,while in simulated flue gas atmosphere,when there was water vapor,the NO reduction efficiency by C3H6 was higher than that by C3H8 at fuel rich conditions and lower than that by C3H8 at oxygen rich conditions.