年产9.8万吨异丙醇装置丙烯精制工段工艺设计----脱乙烷塔部分

年产9.8万吨异丙醇装置丙烯精制工段工艺设计

----脱乙烷塔部分

摘要

丙烯是石油化工的原料之一，在原油加工中具有重要作用。由裂解气净化与分离工段的丙烯精馏塔分离出的丙烯除了用于生产聚丙烯外，还大量地作为生产丙烯腈，丁醇，辛醇，环氧丙烷，异丙醇等产品的主要原料。为了更好的提高生产能力，本着投资少，能耗低，效益高的想法，本设计根据设计任务书中确定的生产任务进行的，年产9.8万吨异丙醇，开工周期为8000小时/年，原料组成为乙烷、丙烯、丙烷、异丁烷，其中丙烯含量为74.1%，按其各组分的沸点和相对挥发度的不同使各组分分离。

由于对丙烯纯度要求极高，本文设计的精馏塔塔板数较多，丙烯塔较高。最后以优化后的精馏塔结果为基础，确定了该塔的设备参数，塔径，浮阀塔盘，塔高，热负荷，从而设计了塔底再沸器，塔顶冷凝器以及塔体主要设备。流程简单，投资较少，操作较为简单，基本可以满足丙烯优等品的工业生产。

本设计采用多组分精馏，按挥发度递减流程方案，两塔流程设计即先经过脱乙烷塔塔顶分离出乙烷，再由丙烯塔精馏塔塔顶得到丙烯，其纯度为93.5%以上，丙烯作为产品出装置为生产异丙醇提供原料，塔底的丙烷可作为商品出售或作为烧火油。

设塔设备一般分为级间接触式和连续接触式两大类。前者的代表是板式塔，后者的代表则为填料塔，在各种塔型中，当前应用最广泛的是筛板塔与浮阀塔。

设计时依次进行了物料衡算，热量衡算，塔结构的相关工艺计算，换热设备的计算及附属设备的选型，并根据设计数据分别绘制了自控流程图，设备选型方面主要按照现场实际，并兼顾工艺控制要求与经济的合理性。

随着先进控制技术的兴起，关键控制指标由定值控制向区间控制转变，调节变量与控制变量的关系由单对单向多变量预估控制转变。它是装置控制技术发展的方向，正在逐步普及。为了为装置以后上先进控制提供方便，我们在设计时，注意为塔顶温度，塔底温度，回流量等指标保留较大的操作弹性。

关键词：丙烯；脱乙烷塔；热量衡算；物料衡算；丙烯精馏塔。

Annual output of 98,000 tons refined isopropyl alcohol propylene Process Design Section --- Deethanizing Tower

Abstract

Propylene is one of raw materials for Petrochemical industry，it occupies an important place in the processing of crude oil. Rectifying column purified and seprated pyrolysis gas to get propylene that largely uses to product principal raw material of the acrylonitrile, butyl alcohol, octyl alcohol, propylene epoxide and isopropanol.In order to improve production capacity with low investment and power,high benifit,Title I design production capacity is 98,000 tons annual output of isopropyl alcohol, started a period of 8,000 hours / year, material composition of ethane, propylene, propane, butane, propylene is 74.1% in material, boiling point of each component and its relative volatility differences of degree of separation of each component. Due to high propylene purity requirement, this paper design the column plate number is more, the propylene tower is higher. Finally based on the results of optimized distillation, determined the equipment parameters of the tower, tower diameter, float valve tray, high tower, heat load, so as to design the bottom reboiler, the overhead condenser and tower body of the main equipment. Simple process, less investment, the operation is relatively simple, basic can satisfy the industrial production of propylene classy article.

The design uses a multi-component distillation, the process by decreasing volatility program, process design the two towers that is, first isolated by de-ethane ethane tower, tower distillation top separated from the ethane , top of the propylene tower geit that propylene, the purity of 93.5%, and propylene as the product of a device to provide raw materials production and isopropanol, the bottom of the propane can be sold as a commodity or as fires, oil.

A tower equipment generally divided into two types: contact and continuous contact between level. Is the former representative of the plate column, the latter represents the packed tower, in all kinds of tower, currently the most widely used is the sieve plate tower and float valve tower.

In turn the design of the material balance, heat balance, the tower structure of the relevant process calculation, the calculation of heat transfer equipment and ancillary equipment selection, and the data were plotted according to the design automation flow, selection of equipment in accordance with terms of the main site practical, taking into account the requirements of process control and economic rationality.