深度醚化单元甲醇回收工艺优化

Optimization of Methanol Recovery Process in Deep Etherification Unit

丁烯氧化脱氢制丁二烯项目所用的原料一般为混合碳四,这些混合碳四往往含有少量的异丁烯及甲醇等杂质,目前一般采用深度醚化技术将这些组分除去。丁烯氧化脱氢制丁二烯项目原料碳四携带异丁烯含量较少而甲醇相对较多,从而使深度醚化单元回收甲醇量大于醚化反应所需的甲醇消耗量,需对过剩的回收甲醇进行储存及销售。如果深度醚化单元工艺过程与常规碳四醚化装置完全相同,则深度醚化单元甲醇回收塔顶的回收甲醇含少量碳四,饱和蒸气压高,储存及运输不方便。为了使过剩的回收甲醇便于储运以及满足销售质量要求,需对甲醇回收塔工艺流程进行优化。本文利用流程模拟技术,对深度醚化单元甲醇回收塔工艺进行优化。

The feed of the oxidative dehydrogenation of butene to butadiene plant is generally mixed C4, which often contain a small amount of impurities such as isobutene and methanol. At present, deep etherification technology is generally used to remove these components. In the butene oxidative dehydrogenation to butadiene, the content of isobutene carried by C4 raw material is less and there is relatively more methanol, so that the amount of methanol recovered by the deep etherification unit is greater than the methanol consumption required by the etherification reaction. The excess recovered methanol needs to be stored and sold. If the process of the deep etherification unit is exactly the same as that of the conventional C4 etherification unit, the recovered methanol on the top of the methanol recovery column of the deep etherification unit contains a small amount of C4, the saturated vapor pressure is high, and the storage and transportation are inconvenient. In order to facilitate the storage and transportation of excess recovered methanol and meet the sales quality requirements, the process of methanol recovery column needs to be optimized. In this paper, the process of methanol recovery column in deep etherification unit was optimized by using process simulation technology.