蜂窝载体负载V_2O_5-WO_3/TiO_2NH_3-SCR试验研究

针对一使用SCR技术满足欧Ⅳ排放标准的柴油机排气特征,在连续流动固定床反应器上利用NH3作还原剂对一纳米级V2O5-WO3/TiO2催化剂的选择性催化还原NO进行了试验研究,分析了不同温度、空速、NH3与NO物质的量比对NOx转化性能的影响。试验结果表明,温度对催化还原性能的影响最大。在低温下,NOx的转化效率很低,随着反应温度的升高,NOx转化率随之急剧升高,在300℃~450℃范围内达到较高的NOx转化效率;随着NH3与NO物质的量比的增加,还原效率并未明显增加,但NH3的氧化和泄漏越来越严重;空速对低温还原效率也存在影响。

Experimental Study on NH3-SCR of Honeycomb Carrier Load V2O5-WO3/TiO2

For making diesel engine emission satisfy Euro Ⅳ criterion with SCR technology,an experiment on NO selective catalytic reduction of V2O5-WO3/TiO2 catalyst with NH3 reductant was carried out in continuous fixed bed reactor.The influence of different temperature,space velocity(SV),NH3/NO mole ratio on NOx conversion performance was also analyzed.Results show that the main factor that affects DeNOx efficiency is temperature.The higher temperature promotes the oxidization of NH3 while the lower temperature decreases reduction efficiency.The optimal temperature range for DeNOx efficiency is about 300 ℃~450 ℃.The increase of NH3/NO mole ratio will not improve the DeNOx efficiency,but the oxidization and leakage of NH3 will be more and more serious.It is also found in the test the SV has the influence on the overall DeNOx efficiency in lower temperature.