乙烯装置脱甲烷塔开车问题分析及应对措施

ANALYSIS AND COUNTERMEASURES FOR PROBLEMS IN START-UP OF DEMETHANIZER IN ETHYLENE PLANT

对某乙烯装置开工过程中,因脱甲烷塔再沸器失效,导致塔釜超低温,超过管道设计温度,再沸恢复过程中导致塔顶温度过高,组分紊乱等一系列次生波动问题进行了原因分析,并提出改进方案,同时进行技术改造,确保装置安全稳定运行。针对脱甲烷塔塔顶冷凝器推动力不足的问题,提出了优化改进方案,改进后,塔顶温度达标,换热效果明显改善,塔顶乙烯损失大幅降低,提高了乙烯回收率。

During the start-up of an ethylene plant,the failure of reboiler in the demethanizer resulted in ultra-low temperature in the bottom of the tower,exceeding the design temperature of pipelines,and a series of secondary fluctuations during reboiling recovery such as the excessively high overhead temperature of the tower and the component disorder.The causes of these problems were analyzed,some improvement plans were proposed and technical modification was carried out to ensure the safe and stable operation of the plant.In view of the insufficient driving force of overhead condenser in the demethanizer,an optimization and improvement plan was proposed.After implementation,the overhead temperature reached the standard,the heat exchange effect was obviously improved,the ethylene loss at the top of the tower was significantly decreased and the ethylene recovery was improved.