催化裂化烟气脱硫脱硝装置的腐蚀问题及对策

Corrosion Problems and Countermeasures of Fluidized Catalytic Cracker Flue Gas Desulfurization and Denitration Device

通过对6家企业11套催化裂化烟气脱硫脱硝装置进行腐蚀调研,了解装置设备和管线的实际腐蚀状况,发现腐蚀隐患,对腐蚀发生原因和影响腐蚀的因素进行了总结、分析和探讨,并从材质防腐和工艺防腐方面提出了应对策略,以期为新建催化裂化烟气脱硫脱硝装置的设计和已建装置的改造提供借鉴。调查表明,催化裂化烟气脱硫脱硝装置只在局部区域出现了严重的腐蚀问题。发生腐蚀的原因主要有:腐蚀环境复杂恶劣,但耐蚀材料的选材等级偏低;结构设计不合理;工艺介质中的腐蚀性物质超出正常控制范围。

Based on corrosion investigation of 11 sets of flue gas desulfurization and denitration devices of fluidized catalytic crackers(FCC) located in 6 different enterprises, the actual corrosion status of the relevant devices and pipelines was acquired, and the corrosion related hiddendangers were found.The causes of corrosion and the factors affecting corrosion were summarized, analyzed and discussed.In order to provide reference for the design of new FCC flue gas desulfurization and denitration device and the modification of existing equipments. The countermeasures for corrosion protection were put forward based on the consideration of two aspects related with material performance and process engineering. According to the investigation, serious corrosion problems only emerged at certain local areas in flue gas desulfurization and denitration devices. Which may be ascribed to the following items, namely the harsh corrosivity of environment, especially the among of corrosive substances even beyond the normal level for the processing medium, the inappropriate selection of materials especially in anti-corrosion performance and errors in equipment design etc.