PET装置原料预热系统优化设计  

Optimization design of raw material preheating system for PET plant

作　　者：刘青青 LIU Qingqing(China Kunlun Contracting&Engineering Corporation,Beijing 100037)

机构地区：[1]中国昆仑工程有限公司,北京100037

出　　处：《合成纤维工业》2020年第4期68-71,共4页China Synthetic Fiber Industry

摘　　要：针对聚对苯二甲酸乙二醇酯(PET)装置常规的生产工艺流程中,酯化蒸汽的回收利用仅用来预热回用乙二醇(EG),其利用率低且流程繁琐的缺点,提出了PET原料系统的优化设计。即在浆料调配槽和第一酯化釜间,增设浆料预热器,用酯化蒸汽预热浆料调配槽出口的浆料,将浆料预热至80℃后再进入第一酯化釜,通过提高原料温度来降低第一酯化釜的热媒消耗;在浆料预热器顶部设置不凝气的排放装置,以使其顶部的不凝气可跟其他尾气一起送至热媒站焚烧处理;浆料预热器设置旁通管线,以保证浆料预热器的清洗,使PET装置平稳运行;浆料预热器选用立式内外凹凸特型管,能有效提高换热效率,避免浆料堵塞,缩短预热器的清洗周期,且占地小,实现在不增加公用工程消耗的情况下,最大程度利用酯化蒸汽的能量提升原料温度。选择立式内外凹凸特型管换热器作为浆料预热器加热PET装置的全部浆料的流程优化设计,为PET企业酯化蒸汽的利用提供了一种新的途径,对于600 t/d PET装置,每年可产生经济效益68.27万元。The recovery and utilization of esterification steam is only used to preheat recycled ethylene glycol(EG)in the conventional production process of polyethylene terephthalate(PET)plant,which has the disadvantages of low utilization rate and tedious process.The optimization design of PET raw material preheating system was proposed to solve the disadvantages.That is to say,a slurry preheater was added between the slurry mixing tank and the first esterification kettle to preheat the slurry at the outlet of the slurry mixing tank with esterification steam to 80℃before entering the first esterification kettle,so as to reduce the heat medium consumption of the first esterification kettle by increasing the raw material temperature;a non-condensable gas discharge device was arranged at the top of the slurry preheater so that the non-condensable gas at the top could be sent to a heat medium station together with other tail gas for incineration;the slurry preheater was equipped with a bypass line to ensure the cleaning of the slurry preheater and the smooth operation of the PET plant;and the slurry preheater adopted vertical internal and external concave-convex special tubes,which could effectively improve the heat exchange efficiency,avoid slurry blockage,shorten the cleaning cycle of the preheater,and reduce the land occupation,so as to maximize the utilization of esterification steam energy to raise the raw materials temperature without increasing the consumption of public projects.The process optimization design of selecting a vertical special concave-convex-tube heat exchanger for slurry preheater to heat the slurry offers PET enterprises a new way to utilize esterification steam and produces an annual economic benefit of 682700 yuan for a 600 t/d PET plant.

关 键 词：聚对苯二甲酸乙二醇酯 生产装置 酯化蒸汽 回收利用 原料 浆料预热器 设计优化 

分 类 号：TQ323.4[化学工程—合成树脂塑料工业]