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

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,