某600MW机组空气预热器硫酸氢铵堵塞综合防治技术

Comprehensive control technique of ABS blockage of air preheater in a 600 MW unit

针对某600MW机组烟气超低排放改造后,空气预热器(空预器)出现严重堵塞现象,提出了空预器硫酸氢铵(ABS)堵塞综合治理技术。通过分区控制格栅式喷氨系统,解决了选择性催化还原(SCR)脱硝装置氨逃逸超标问题,将空预器传热元件三段改为两段,提高了空预器吹灰的通透性,空预器ABS堵塞现象得到了根治,提高了机组运行的安全性和经济性。本文对同类型问题机组改造具有一定的借鉴意义。

To solve the serious blockage occurred in air preheater after ultra-low emission transformation of a 600 MW unit, a set of comprehensive treatment technology for ABS blockage of the air preheater was put forward. Through the zone control grid type ammonia injection system, the problem of SCR ammonia escape exceeding the standard was solved, and the heat transfer elements with three-layer structure in the air preheater was transformed into two-layer structure, which improved the air preheater’s soot blowing permeability, and the ABS blockage of the air preheater was solve completely, therefore the safety and economy of the unit operation were improved. The conclusion of this paper provides reference for the retrofit of units with the same type of problems.