MTBE合成装置醚后C_4中甲醇和二甲醚含量高的原因分析及对策

CAUSE ANALYSIS AND CONTERMEASURES OF HIGH METHANOL AND DME CONTENTS IN ETHERIFIED C4 FRACTIONS OF MTBE UNIT

分析北京燕山石油化工有限公司MTBE合成装置醚后C4中甲醇及二甲醚含量高的原因,通过采取更换甲醇萃取塔、用MTBE裂解装置甲醇回收塔替代MTBE合成装置的甲醇回收塔、提高催化剂活性、用近红外在线分析仪准确控制反应的进料醇烯比等措施,醚后C4中甲醇及二甲醚含量从1 000μg/g以上分别降低到甲醇含量不大于50μg/g、二甲醚含量不大于500μg/g,可满足下游装置烷基化生产的需要。

The causes of high methanol and DME contents in etherified C4 fractions of MTBE synthesis unit at Yanshan Petrochemical Company were analyzed. Measures including the replacement of methanol extraction tower, using methanol recovery column of MTBE cracking unit as the methanol recovery column of MTBE synthesis unit, increase catalyst activity and properly control the ratio of methanol to olefin in feed, were adopted. Since then the methanol content and DME content in etherified C4 fractions was dropped from more than 1 000 μg/g to less than 50 μg/g and less than 500 μg/g, respectively, which could meet the requirements of downstream alkylation process.