应用于船舶尾气NO_(x)去除的SCR催化剂涂覆工艺影响因素研究

Coating technology research of SCR catalysts used for marine NO_(x) removal

涂覆工艺对于整体式涂覆型SCR催化剂至关重要。通过对催化剂浆料制备过程以及涂覆过程中的关键影响因素的探究,考察了分散剂、增稠剂及对应添加量、pH和固含量对浆料涂覆效果及活性测试结果的影响。通过比较不同涂覆方式、浆料搅拌时间、干燥温度及时间、成型焙烧温度及时间,对涂覆工艺进行过程优化选择。结果表明:通过最优方案制备的涂覆型催化剂在250~450℃的条件下反应活性均在85%以上,在315℃的条件下运行30 h脱硝活性仍能稳定在90%以上。系统地梳理了涂覆过程中关键参数的选择及应用,为整体式蜂窝状涂覆式催化剂的制备提供了指导。

Coating technology is very important to the monolithic coated SCR catalyst.The key factors affecting the preparation process of the slurry and the coating process were investigated in this paper.The effects of dispersant,thickener,pH,and solid content on the coating effectiveness and activity test results were studied.Different coating methods,slurry stirring durations,drying temperatures and times,as well as calcination temperatures and durations,were compared to optimize the coating process.It is shown that the SCR activity of coated catalysts prepared under the optimal conditions exceeds 85%in the range of 250-450℃.The denitrification activity can still be stable at over 90%at 315℃for 30 h.In this paper,the selection and application of key parameters in the coating process are systematically studied,which will provide guidance for the preparation of the monolithic honeycomb coated catalysts.