Abstract:

This article introduces the technical transformation of the 250 000 TPY MTBE(methyl tert-butyl ether) unit in the light hydrocarbon center of Yan'an Petrochemical Plant, Shaanxi Yanchang Petroleum(Group) Co., Ltd. The concrete reform contents are as follows. The original design ball tank of exited materials in MTBE plant is transformed into the ball tank of rich isobutene, achieving a stable mass fraction of isobutene in MTBE reaction material at about 43%, ensuring the stability of the MTBE unit's reaction ratio of methanol. The catalytic distillation column utilizes the regenerated C₄ flow line returning post-ether C₄ to the bottom of the column, which forms a single-column operation mode with the residual methanol after methanol soaking in the early stage. A recycling process is added at the bottom of the catalytic distillation column, and the MTBE product meets the qualification requirement of a mass fraction higher than 98.5% after repeated purification. Through industrial production practice verification, a new MTBE driving method has been developed, which meets the requirement of high concentration wastewater discharge content less than 0.01%(mass fraction).

Key words: MTBE unit, new start-up scheme, isobutene, product purity, alcohol-to-vinyl ratio, regenerated C₄, post-ether C₄, unqualified product, recycling,

摘要：

介绍了陕西延长石油(集团)有限责任公司延安石油化工厂轻烃中心250 kt/a MTBE(甲基叔丁基醚)装置技术改造情况。具体改造内容：将MTBE装置原设计退料球罐改为原料富异丁烯球罐，实现了MTBE反应物料中异丁烯的质量分数稳定在43%左右，保证了MTBE装置反应配比甲醇的稳定性；催化蒸馏塔通过再生C₄流程线，返回醚后C₄至塔底的循环流程，与前期剩余的甲醇形成单塔运行模式；催化蒸馏塔塔底增设回炼流程，MTBE产品经过反复提纯后满足质量分数高于98.5%的合格要求。通过工业化生产实践验证，该方案开辟了一种新型的MTBE装置开车方法，满足了高浓废水排放的要求。

关键词: MTBE装置, 新型开工方案, 异丁烯, 产品纯度, 醇烯比, 再生C₄, 醚后C₄, 不合格产品, 回炼