Optimization and experimental study of vertical double wall dividing-wall column for separating a quaternary system

doi:10.11949/j.issn.0438-1157.20171552

Abstract

Abstract:

A vertical double wall divided-wall column separating four-component mixture was proposed. The structure design of the tower was introduced and explained in detail. According to the structure and separation principle of the new divided-wall column, the five-tower model was designed and a shortcut design calculation was conducted. For the complete thermal coupling process of the four components separation of the hydrocarbon system, the simulation optimization and energy analysis were carried out by using the chemical engineering process simulation software Aspen. Compared with the general sequence tower separation process, the energy saving of the new divided-wall column was up to 18.6% and energy saving effect was obvious. By using the process simulation, a small pilot study was conducted on the new trays by using pentane, hexane, heptane and octane as separators. The results show that the main factor affecting the temperature distribution of the new divided-wall column is the spilt liquid ratio. The temperature distribution in the main tower section two could be controlled by controlling the reflux of the overhead condenser in the main tower section two of the new divided-wall column. Through the research of this paper, the theoretical basis and design reference for the industrialization of the separation of the four-component mixture in the new divided-wall column are provided.

Key words: DWC, Aspen, shortcut design method, simulation and optimization, five-column model

摘要：

提出了一种垂直双隔板的分离四组分混合物的隔壁塔，对该塔的结构设计进行了详细的介绍和说明，根据新型隔壁塔的塔板结构和分离原理设计了该种塔板的五塔模型并进行了简洁计算。针对烃类体系四组分分离的完全热耦合过程，通过化工流程模拟软件Aspen进行了模拟优化和用能分析，相比一般的序列塔分离工艺，节能最高可达18.6%，节能效果明显。根据工艺模拟结果，以分离戊烷、己烷、庚烷、辛烷为研究对象，对新型塔板进行了小试研究。研究结果表明：影响新型隔壁塔温度分布的主要因素是液相分配比，可通过控制新型隔壁塔主塔段二塔顶冷凝器的回流量来控制主塔段二的温度分布。研究为隔壁塔气相分配的工业化提供了理论依据和设计参考。

关键词: DWC, Aspen, 简洁设计方法, 模拟优化, 五塔模型

CLC Number:

TQ053.5

WANG HongHai, WANG Baozheng, LI Chunli, JI Pengyu. Optimization and experimental study of vertical double wall dividing-wall column for separating a quaternary system[J]. CIESC Journal, 2018, 69(7): 3050-3058.

王洪海, 王宝正, 李春利, 姬鹏宇. 垂直双隔板隔壁塔分离四组分的模拟优化和实验研究[J]. 化工学报, 2018, 69(7): 3050-3058.

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