MTO装置余热锅炉炉管泄漏原因分析

Analysis on Causes of Leakage of Waste Heat Boiler Tubes in MTO Device

对某煤化工公司MTO装置余热锅炉过热段发生爆裂泄漏的炉管进行调查分析,通过宏观检验,化学组分分析,金相显微组织检测,力学性能检验的方法,找出炉管泄漏原因。过热段炉管泄漏与其工艺操作调整和炉管内壁结垢有关,长时间过热产生高温蠕胀,引起炉管内外壁升温氧化,加速金属组织球化现象,使其力学性能下降,在高温高压环境下,炉管内壁变薄并出现纵向裂纹,最终导致炉管强度不足以承受高压而发生爆裂泄漏。防范措施建议优化工艺操作,监控水质。

This paper investigates and analyzes the furnace tube bursts and leaks where the superheating sec. tion of the MTO device waste heat boiler of a coal chemical company. Through macroscopic inspection, chemical composition analysis,metallographic microstructure inspection,and mechanical property testing meth. od,the cause of furnace tube leakage is found. The leakage of the superheated furnace tube is related to the adjustment of the process operation and the scaling of the inner wall of the furnace tube. The long-term overheating generates high temperature creep,which causes the inner and outer walls of the furnace tube to heat up and oxidize,accelerate the spheroidization of the metal structure,and reduce its mechanical proper. ties. Under high temperature and high pressure environment,the inner wall of the furnace tube is thinned and longitudinal cracks appear, which eventually causes the tube strength to be insufficient to withstand high pressure and burst leakage. Precautionary measures recommend that optimize process operations and mon. itor water quality.