乙酸乙酯装置精馏系统的工艺优化

Process Optimization of Distillation System in Ethyl Acetate Plant

针对乙醛缩合法制乙酸乙酯的装置精馏系统中出现的因反应液中乙醛含量低而影响乙醛回收塔操作,以及因反应液中催化剂破坏液加入量不易控制而导致乙醇回收塔操作不稳定等问题,采取了暂时放弃乙醛回收,将乙醛回收塔顶液作为破坏液使用以稳定精馏系统操作等措施,确保产出合格乙酸乙酯成品。在此基础上,采取了从乙醛回收塔的塔顶回收乙醛,将侧线出料用作破坏液;使成品塔塔顶液全部回流,从侧线采出成品乙酸乙酯,加大塔釜液排放量并对其进行回收处理等一系列工艺优化措施,解决了因放弃乙醛回收而造成的成品乙酸乙酯质量下降和乙醛单耗上升等问题。

In the distillation system of ethyl acetate plant with acetaldehyde condensation method, the low acetaldehyde content in reaction liquid affects operation of acetaldehyde reclaiming tower and the hard controllable pure water destruction liquid dosage in the reaction liquid caused unstable operation of ethanol reclaiming tower, so the reclamation of acetaldehyde is suspended. Instead, the top liquid of acetaldehyde reclaiming tower is applied as destruction liquid to stabilize the operation of distillation system to ensure acceptable ethyl acetate product is produced. Based on this, a series of process optimization measures are adopted such as reclaiming acetaldehyde in the top of acetaldehyde reclaiming tower, using side - draw stream discharge as destruction liquid, infinite reflux in top of finished product tower, collecting ethyl acetate product from side draw,increasing discharge amount of fluidized bed and recovering it. Consequently, the problems of quality decline of ethyl acetate product and increase of acetaldehyde single energy consumption caused by suspension of acetaldehyde reclamation are solved.