烟气联合脱硝技术在重油催化裂化装置上的工业应用

摘要

The regeneration flue gas denitrification system in a 3.5 Mt/a residue fluid catalytic cracking unit was reformed by flue gas combined denitrifica-tion technologies of selective non - catalytic reduc-tion(SNCR)and selective catalytic reduction (SCR).The reformation measures were taken,inclu-ding the 1 layer SCR catalyst module was added be-tween evaporator and coal economizer,2 layer SNCR spraying ammonia components were added in the high temperature zone of the incinerator,and 6 am-monia spray guns were setup uniformly at every lay-er.The unit running results showed that after trans-formation,the mass concentration of NOxin cleaning flue gas reduced from 500 mg/m3to 145 mg/m3,it could meet the requirement of GB 31570—2015, and the system pressure drop(0.2 kPa)was lower than design value(0.5 kPa).%采用选择性非催化还原(SNCR)与选择性催化还原(SCR)烟气联合脱硝技术对350万 t/a重油催化裂化装置再生烟气脱硝系统进行了工艺改造,改造措施包括在蒸发器与省煤器间置入1层 SCR催化剂模块及在焚烧炉高温区设置2层 SNCR喷氨组件、且每一层均匀安装6支喷氨枪.改造后装置运行结果表明:净化烟气中 NOx的质量浓度由改造前的500 mg/m3下降至145 mg/m3,满足 GB 31570—2015的要求;系统压降(0.2 kPa)低于设计值(0.5 kPa).