选择性催化还原(SCR)脱硝技术在液态排渣炉上的应用

Application of SCR Technology in Slag Tapping Boiler

选择性催化还原(SCR)是一种成熟的电厂烟气脱硝技术,正在国内外得到广泛的应用。液态排渣炉由于其燃烧温度高,其飞灰在粘性、细度及烟气中微量元素的含量等方面与固态排渣炉有较大的不同。文章论述了在液态排渣锅炉上实施SCR时的关键工艺选择,如SCR出口NOx浓度、脱硝率、氨逃逸量的关系;高灰段布置砷中毒的问题;催化剂类型及排列布置方式选择等。文章还提出了SCR改造工程中需要注意的问题,讨论了实施SCR以后对锅炉的影响,提出了具体的解决对策。

The selective catalytic reduction （SCR） technology is a mature flue gas denitration technology for thermal power plant,being widely used at home and abroad.As a result of high combustion temperature of slag tapping boiler,the viscosify, fineness of its flyash and the trace element content of its flue gas etc. are considerably different from those of dry bottom boiler.This article discusses the selection of key technologies ha the implementation of SCR ha slag tapping boiler,such ascthe rehtionship of exit NOx concentration,denitration rate and slip quantity of ammonia of SCR;the arsenic poisoning problem ha high ash section layout;the selection of catalyzer type and arrangement - layout scheme etc.The article also puts for ward the matters needing attention h the SCR retrofitting project, discusses the impact on the boiler after implementation of SCR and raises the concrete solving countermeasures.