乙烯装置深冷区甲烷泵密封液泄漏的分析和对策

ANALYSIS AND COUNTERMEASURES FOR SEALING LIQUID LEAKAGE OF METHANE PUMP IN CRYOGENIC ZONE OF ETHYLENE PLANT

乙烯蒸汽裂解技术中,深冷区的甲烷泵通常采用带压甲醇作为密封液,要求密封液压力比泵出口压力高,存在甲醇内漏到介质中,被工艺介质带入深冷区的孔径较小的设备和管件中,导致冻堵现象,造成乙烯损失剧增,增加了甲烷化反应器潜在飞温隐患。文中就几次处理过程,总结甲醇内漏的影响、现象判断和处理措施。

In ethylene steam cracking technology,methanol is often used as the sealing fluid for methane pump in cryogenic zone,and the pressure of sealing liquid is required to be higher than the outlet pressure of the pump. Methanol may leak into the medium and be entrained by the process medium into equipment and pipe fittings with relatively small aperture in the cryogeniczone,resulting in frozen blockage and then a dramatic increase in ethylene loss, thus increasing the potential hidden danger of temperature runaway of the mathanation reactor. This paper summarizes the impacts, judgement and countermeasures for methanol leakage.