催化裂化烟气湿法脱硫装置设备腐蚀现状分析及对策

Current Situation Analysis and Countermeasures for Corrosion of Wet Desulfurization Unit of FCC Flue Gas

随着国家工业排放标准要求的提高,中国石化对催化裂化装置再生烟气增设了脱硫、除尘装置,其中EDV洗涤和双循环湍冲文丘里湿法脱硫除尘技术应用广泛。在脱硫装置运行中出现了较多的设备腐蚀问题,如塔壁、烟囱腐蚀减薄及穿孔泄漏,浆液喷嘴等塔内件腐蚀及磨损,浆液循环泵叶轮腐蚀减薄等,影响装置长周期稳定运行。针对上述问题,分析了设备腐蚀机理和原因,从工艺控制、设计改进、有机高分子材料选用、材质升级、材料采购和施工质量控制等几个方面提出了应对措施和建议,为治理腐蚀和保证脱硫装置长周期运行提供借鉴。

With the improvement of national industrial emission standards, additional devices of desulphurization and dust removal were set in Sinopec catalytic cracking units, of which the EDV washing and double circulation turbulent Venturi wet de- dusting and desulphurization technologies are widely applied. However, there are many equipment corrosion problems, such as corrosion thinning of tower wall and chimney, perforation-caused leakage, corrosive wear of tower internals, corrosion thinning of the impeller of slurry pump, etc. In view of above problems, equipment corrosion mechanism and reasons were analyzed; countermeasures and suggestions were put forward from the aspects of process control, design improvement, material procurement, construction quality control, material upgrading and organic polymer material selecting, which provide reference information for corrosion prevention and desulfurization unit operation.