10万吨/年环氧丙烷车间工艺设计与优化
摘 要
环氧丙烷是重要的有机化工原料，传统的生产方法产生大量废水废渣或大量联产品。过氧化氢直接氧化法（HPPO）在TS-1催化剂催化下使过氧化氢直接氧化丙烯，理论副产物只有水，反应转化率高，选择性高，属于环境友好的合成路线。
环氧丙烷的需求量逐年增长，而目前国内产能大部分为氯醇法工艺，设备老旧腐蚀严重，环保处理难，面临淘汰，HPPO法有良好的发展空间。
使用Aspen Plus软件对HPPO法生产环氧丙烷进行研究，模拟10万吨/年环氧丙烷车间工艺流程，确定相关操作参数，并使用灵敏度分析工具对各塔进料位置进行优化。甲醇作为体系内溶剂，用量大，然而使用原有的单塔精馏回收甲醇耗能高，本文采用双效精馏回收甲醇，使高压塔塔顶冷凝器与常压塔再沸器热耦合，对比单塔精馏回收可节约能耗35.8%。
在化工生产中，换热设备所需的装置费用约占装置成本的近30%和运行费用的近90%，选择合适的换热器能显著降低成本，然而换热器结构复杂，流体流动状态难以预测，不易计算。为提高计算准确性，本文使用Aspen EDR软件设计环氧丙烷分离塔再沸器。
关键词：环氧丙烷；直接氧化法；流程模拟
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10万吨/年环氧丙烷车间工艺设计与优化
Process Design and Optimization for 100kton/y Propylene Oxide Plant
Abstract
Propylene oxide is an important raw material of organic chemical engineering, the traditional production process will produce a large number of waste water or coproducts. Hydrogen peroxide Process (HPPO process) catalyzes the direct oxidation of propylene over hydrogen peroxide catalyzed by TS-1 catalyst. The theoretical byproduct is water, the reaction have high reaction conversion and high selectivity, and is an environmental friendly synthetic routes.
Propylene oxide demand growth year by year, and most of the current domestic production capacity is chlorine alcohol process, which the equipment was serious corrosion, environmental management difficult, HPPO process has a good development space.
This article use Aspen Plus software to simulate the process for 100kt/a propylene plant. determine the relevant operating parameters, and use the sensitivity analysis tool to optimize the feed stage of towers. The recycle of methanol cost huge energy, this paper uses double-effect distillation to recycle methanol as solvent. Compared to single tower distillation , this process can save energy consumption about 35.8%.
In the chemical production, the heat exchanger equipment costs about 30% of the equipment cost and nearly 90% of the operating costs. That means select an appropriate heat exchanger can significantly reduce the cost, but it is hard to calculate the heat exchanger because of the complex structure and unpredictable fluid flow. This article uses the Aspen EDR software to design the reboiler of propylene oxide separation column reboiler, improve the accuracy of design.
Key Words：Propylen Oxide；HPPO Process；Process simulation
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10万吨/年环氧丙烷车间工艺设计与优化
目 录
摘 要 ..................................................................................................................................... I 1 文献综述 .............................................................................................................................. 1
1.1 环氧丙烷介绍 ........................................................................................................... 1
1.1.1 环氧丙烷性质 ................................................................................................ 1 1.1.2 环氧丙烷应用 ................................................................................................ 1 1.2
1.2.2
环氧丙烷生产工艺 ................................................................................. 2
1.2.1 氯醇法 ............................................................................................................ 2
共氧化法 ................................................................................................. 4
1.2.3 过氧化氢直接氧化法 .................................................................................... 6 1.3 环氧丙烷市场供需情况 ........................................................................................... 7
1.3.1 环氧丙烷消费现状 ........................................................................................ 7 1.3.2 环氧丙烷生产现状 ........................................................................................ 8 1.1 2
TS-1催化剂 ............................................................................................ 9
工艺流程模拟 ..................................................................................................................... 9 2.1 反应器 ......................................................................................................................... 9 2.2 丙烯分离塔 ............................................................................................................. 10
2.2.1 简捷计算 ...................................................................................................... 10 2.2.2 严格计算 ...................................................................................................... 12 2.2.3 最佳进料位置 .............................................................................................. 13 2.3 环氧丙烷分离塔 ..................................................................................................... 14
2.3.1 简捷计算 ...................................................................................................... 14 2.3.2 严格计算 ...................................................................................................... 16 2.3.3 最佳进料位置 ................................................................................................ 17 2.4 环氧丙烷提纯塔 ....................................................................................................... 18
2.4.1 简捷计算 ...................................................................................................... 19 2.4.2 严格计算 ...................................................................................................... 21 2.4.3 最佳进料位置 .............................................................................................. 21 2.5 溶剂回收 ................................................................................................................. 23
2.5.1 甲醇常规精馏 .............................................................................................. 23 2.5.2 甲醇双效精馏 .............................................................................................. 25 2.5.3 甲醇回收工艺对比 ...................................................................................... 26
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10万吨/年环氧丙烷车间工艺设计与优化
2.6 小结 ......................................................................................................................... 27 3
换热器选型及设计 ........................................................................................................... 27 3.1 设备选型 ................................................................................................................. 27 3.2 工艺数据 ................................................................................................................. 28 3.3 物性数据 ................................................................................................................. 29 3.4 结构数据 ................................................................................................................. 29 3.5 热虹吸管线 ............................................................................................................. 31 3.6 设计计算结果分析 ................................................................................................. 31 3.7 圆整数据 ................................................................................................................. 32 3.8 模拟计算结果 ......................................................................................................... 33
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10万吨/年环氧丙烷车间工艺设计与优化
1 文献综述
1.1 环氧丙烷介绍
1.1.1 环氧丙烷性质
环氧丙烷（Propylene Oxide，简称PO）是重要的有机化合物原料，分子式为CH3CHCH2O。环氧丙烷是一种手性环氧化物，通常工业产品为两种异构体的外消旋混合物。在常温常压下为无色透明液体，极其易燃，具有醚类气味。环氧丙烷与水部分互溶，与多种常见有机溶剂互溶（乙醇、乙醚等），其基本物理性质如表1.1所示。
表1.1 环氧丙烷基本物理性质 项目 熔点(℃) 沸点(℃) 相对密度（水=1） 相对蒸气密度（空气=1）
饱和蒸气压(kPa) 燃烧热(kJ/mol) 闪点(℃) 爆炸上限%(V/V) 爆炸下限%(V/V) 溶解度（水，20℃）
环氧丙烷的化学性质十分活泼，容易与水、氨、醇、二氧化碳等发生开环聚合反应。当环氧丙烷接触一些金属无水氯化物（铁、铝、锡），金属过氧化物（铁、铝）以及碱金属氢氧化物等催化剂活性表面时，将聚合放热，产生大量热量导致容器爆炸。环氧丙烷与常见无机酸（盐酸、硝酸、硫酸）及氨水等发生剧烈反应，可能导致爆炸。而环氧丙烷自身遇高热、明火或者氧化剂等均可能引起燃烧爆炸。所以环氧丙烷的生产、装卸、储存等都需要特殊的防火防爆设计，并严密监控。 1.1.2 环氧丙烷应用
环氧丙烷是除聚丙烯和丙烯腈外的第三大丙烯衍生物。环氧丙烷在全球范围内用于生产多种产品，主要是聚醚多元醇（聚乙二醇醚）、丙二醇。在国内用于生产聚醚多元
性质 -104.4 33.9 0.83 2.0 75.86(25℃) 1887.6 -37 37.0 2.8 41%
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10万吨_年环氧丙烷车间工艺设计与优化
