裂解炉急冷锅炉泄漏失效分析

LEAKAGE FAILURE ANALYSIS OF QUENCH BOILER IN CRACKING FURNACE

乙烯装置裂解炉急冷锅炉泄漏失效问题在国内各乙烯装置均有发生,原因也各有不同。针对燕山石化乙烯裂解炉的实际运行情况,通过急冷锅炉泄漏部位的故障类型描述、宏观检查、化学成分分析、金相分析、能谱分析和物相分析等手段对失效原因进行了系统分析和讨论,认为碱腐蚀是导致急冷锅炉腐蚀泄漏的主要原因,而锅炉给水系统杂质含量超标、pH值控制不稳定和磷酸盐腐蚀等因素的共同作用,是导致急冷锅炉发生碱腐蚀的源头。根据分析结论,提出了预防措施及建议。

The leakage failure of quench boiler in cracking furnace occurred in ethylene plants throughout China,and the causes were different. Based on the actual operation of the ethylene cracking furnace at SINOPEC Beijing Yanshan Company, this article systematically analyzes and discusses the reasons for the leakage failure of quench boiler by means of specific location and fault type description, macroscopic examination, chemical composition analysis,metallographic analysis,energy spectrum analysis and phase analysis,and finds out that caustic corrosion is the main reason for the corrosion leakage of quench boiler. The excessively high impurity content of boiler feed water system,the unstable control of pH value and the phosphate corrosion lead to the caustic corrosion of quench boiler. Some preventive measures and suggestions are put forward.