【摘要】 利用携带流脱硝试验装置,研究了反应温度(Tr)、烟气组分(O2、CO、水蒸气)、飞灰以及碱金属添加剂等对选择性非催化还原(selective non-catalytic reduction,SNCR)脱硝效果的影响,探讨了NO还原机理。结果表明:随着反应温度的升高,SNCR脱硝效率呈现先增加后降低的趋势。随着烟气中氧含量的增加,SNCR脱硝效率呈现先快速增加后逐渐降低的趋势,当氧含量为2%时,脱硝效率取得最大值84.6%。烟气中CO存在对SNCR脱硝具有一定的抑制作用。随着烟气中水蒸气含量(0~15%)的增加,脱硝效率呈现先增加后减少并逐渐趋于稳定的趋势,4%水蒸气条件下SNCR脱硝效率达到最大值,约为73.5%。碱金属(钠、钾)添加剂对SNCR脱硝具有显著的促进作用,燃煤飞灰对SNCR脱硝效率则具有一定的抑制作用,添加125μmol/mol Na2CO3的SNCR脱硝效率可达84.9%,在水蒸气、CO、Na2CO3和飞灰的耦合作用下,仍可获得72.1%的脱硝效率。更多还原

【Abstract】 The effects of reaction temperature, flue gas components(O2, CO, water vapor), fly ash and alkali metal additives on NO reduction during the selective non-catalytic reduction(SNCR) process were investigated in an entrained flow reactor, and NO reduction mechanism was also analyzed. The results indicate that: NO removal efficiency of SNCR shows a trend of increase first and decrease later with increasing reaction temperature. NO removal efficiency shows a pattern of rapid increase first and decrease later with increasing oxygen content, and the best NO removal efficiency of 84.6% is obtained when 2% oxygen was used. The additive of carbon monoxide has a certain adverse effect on NO reduction in the SNCR process. NO removal efficiency shows a tendency of increase first, decrease later and being stable gradually with increasing water vapor(0~15%) in the flue gas, and the best NO removal efficiency of 73.5% is obtained at 4% water vapor. Alkali metal(K, Na) additives have significant promoting effects on NO reduction, but the fly ash has a certain adverse effect on NO reduction in the SNCR process. NO removal efficiency through SNCR can reach 84.9% while adding 125 μmol/mol Na2CO3 in the flue gas. NO removal efficiency of SNCR still reaches 72.1% through the coupling effect of water vapor, CO, Na2CO3 and fly ash.更多还原