为解决燃煤电厂SCR烟气脱硝系统运行中日益突出的催化剂磨损问题,对催化剂磨损机理、成因及危害进行分析.总结出应对催化剂磨损的诊断思路和策略,并以某300 MW机组蜂窝式SCR催化剂磨损治理为例,介绍具体的解决方法及步骤.首先对催化剂层磨损分布规律进行测量统计,在确定催化剂单元体机械强度合格的同时,确认蒸汽吹灰器未对催化剂造成吹损;之后通过CFD数值模拟方法对催化剂单孔道和反应器流场进行研究,发现该机组催化剂磨损原因在于催化剂首层局部区域烟气流速不均、入射角偏斜,随即进行了流场优化设计.优化方案实施后,消除了烟气速度场高速区,矫正了入射角角度,有效减轻了催化剂的磨损.%In order to solve the increasingly prominent issue of gas denitration catalyst system abrasion in coal-fired power plants,the mechanism as well as the causes and the damages of the catalyst abrasion are analyzed.The diagnostic idea and strategies are also summarized.Then detailed solution procedures are introduced by taking the example of the catalyst abrasion treatment for a 300 MW unit.Firstly,the distribution statistics of the abrasion was compiled.While sufficient mechanical resistances of the catalyst elements was confirmed,the steam sootblower was verified to cause no blowing loss of catalyst.Secondly,CFD numerical simulation was employed to investigate the flow fields inside both the honeycomb pores and the reactor.The root cause of abrasion was revealed as the extraordinarily high velocity and deviation of injection angle of gas flow at some parts of the upper layer.Afterwards the flow field design was optimized.Since the implementation of optimized plan,the catalyst abrasion has been effectively improved by eliminating the parts with high velocity and adjusting the injection angle of gas flow.The diagnosis strategy to the catalyst abrasion in this investigation is of great significance to solve the practical problem of the power plants.
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