反应精馏研究进展及应用前景

对反应精馏技术在工艺和模拟方面的研究进展进行了概述 ,简单介绍了反应精馏的关键技术并对反应精馏的应用前景进行了展望。     

粗甲醇的双塔精馏与三塔精馏

本文就粗甲醇的双塔精馏和三塔精馏工艺进行了简要剖析,并对这二种工艺在产品质量和能耗方面作了具体比较。     

甲醇精馏技术简述

论述了甲醇精馏技术中双塔和三塔精馏工艺,介绍了采用高效丝网波纹填料和分布器的填料型精馏塔的优点。对双塔和三塔精馏技术的经济性进行了比较。     

甲醇精馏方案技术对比

对粗甲醇的双塔精馏和三塔精馏工艺进行技术方案、投资、消耗、能耗、成本等方面的对比,对采用空冷器时的技术方案进行初步研究,研究结果界定两种工艺方案的适用装置规模。     

连续精馏分离氰乙酸甲酯工艺

针对氰乙酸甲酯传统的间歇精馏分离过程,提出了连续精馏分离氰乙酸甲酯的三塔、四塔和五塔工艺流程,并对3种分离流程进行工艺分析,确定了连续精馏五塔分离工艺.利用ASPEN PLUS软件中的RADFRAC精馏模型和WILSON方程对五塔精馏分离流程进行优化模拟计算,得到了该流程的最佳工艺操作参数及相关的设备参数.生产数据表明,与目前普遍采用的间歇精馏工艺相比,能耗降低了近30%,产品收率提高了2.4%,为氰乙酸甲酯的连续分离开辟了一条新的工艺技术路线.     

新型丙烯酸精馏系统的研究

针对丙烯酸传统共沸精馏系统，通过热力学数据分析，利用水、醋酸和丙烯酸本身的沸点差异，提出了采用直接精馏方式提纯丙烯酸的工艺技术方案。基于Aspen Plus流程模拟软件，对丙烯酸共沸精馏工艺及直接精馏工艺进行了流程模拟与分析，发现采用直接精馏工艺可有效简化丙烯酸精制工艺，并降低丙烯酸精馏单元的能耗，对未来丙烯酸装置的设计及运行具有重要指导意义。     

石油化工企业精馏节能技术的可行性研究分析

节能精馏技术比普通精馏的效率更高并且能减少能量的耗费,通过对液体的回流比、操作压力以及物料的进料位置进行合理的优化。尤其是回流比参数,改变回流比,可以直接的导致精馏过程的能耗增高或者降低。本文重点分析了热泵精馏技术、多塔精馏技术、双塔精馏技术。通过对工业甲醇的节能精馏工艺的案例分析,研究了热泵精馏、三塔精馏技术和双塔精馏技术的节能效果对比。结果表明,三塔精馏节能工艺能够获得良好的使用效果。为我国节能精馏技术在化学应用领域的运用提供了应用参考平台。     

苯乙烯装置乙苯/苯乙烯分离塔节能技术

在石油化工生产过程中,精馏过程无疑是每个装置能量消耗最大的工序之一,为了改善精馏过程高能耗问题,伴随着对常规分离过程不断地调整优化,一些新的工艺应运而生,热泵精馏工艺与多效精馏工艺便在其中且被广泛应用。本文借助流程模拟,对乙苯/苯乙烯分离过程采用常规精馏、热泵精馏技术与多效精馏技术进行了对比分析。分析结果表明,在完成相同分离任务的前提条件下,采用热泵精馏与多效精馏工艺均能够显著降低精馏过程的能耗,具有良好的经济效益和广泛的应用前景。     

吗啉精馏方法的选择

对５００ｔ／ａ吗啉的两种精馏方法进行了技术经济分析，介绍了解决单塔精馏存在问题的方法，得出单塔间歇精馏工艺优于四塔连续精馏工艺的结论。     

热泵变压精馏分离乙二胺水溶液的模拟

基于乙二胺和水物系共沸组成随压力变化显著的特点,采用变压精馏工艺分离乙二胺和水物系;为了降低变压精馏工艺的能耗,提出了热泵变压精馏新工艺。使用Chem CAD软件,对变压精馏工艺和热泵变压精馏工艺进行了模拟。结果表明:采用变压精馏工艺和热泵变压精馏工艺都能实现乙二胺和水共沸物的高纯度分离,每个产品的纯度(质量分数)都可以达到99%;与变压精馏工艺相比,采用热泵变压精馏工艺,加热公用工程可节能62.24%;冷却公用工程可以节能49.51%。     

用于醇–水体系分离技术的研究进展

主要介绍了醇–水体系分离的几种工艺和新方法,其中包括传统的恒沸精馏和萃取精馏等主流工艺,以及膜蒸馏、渗透汽化和膜接触器等新型膜分离技术。在分析以上工艺基本原理的基础上,对其具体的性能参数和操作特点进行了比较。     

异丙醇脱水技术研究进展

主要介绍了异丙醇-水分离的几种工艺和新方法。在介绍异丙醇脱水常规工艺的基础上,重点阐述隔壁共沸精馏、间歇萃取精馏、吸附蒸馏和膜分离法等新工艺,具体分析了各种方法的优缺点及研究情况,并展望了异丙醇-水分离工艺的前景。     

高纯丙酮制备工艺研究

以分析纯丙酮为原料,采用亚沸蒸馏技术,来制备高纯丙酮,纯度可超过99.95%。该技术的关键在于精确控制蒸馏温度和蒸馏次数。     

Design and Control Comparison of Alternative Separation Methods for n‐Heptane/Isobutanol

The binary mixture of n‐heptane and isobutanol forms an azeotrope at atmospheric pressure, with a composition of 66.9 mol % n‐heptane and a temperature of 364 K. Several methods of separation are possible. This study compares the steady‐state economics and the dynamic controllability of three alternative separation techniques: a two‐column extractive distillation process, a two‐column pressure‐swing distillation process, and a single column with a refrigerated condenser.     

Cyclic distillation technology – a mini‐review

Process intensification in distillation systems has received much attention during past decades, with the aim of increasing both energy and separation efficiency. Various techniques, such as internal heat‐integrated distillation, membrane distillation, rotating packed bed, dividing‐wall columns and reactive distillation were studied and reported in the literature. All these techniques employ the conventional continuous counter‐current contact of vapor and liquid phases. Cyclic distillation technology is based on an alternative operating mode using separate phase movement which leads to key practical advantages in both chemical and biochemical processes. This article provides a mini‐review of cyclic distillation technology. The topics covered include the working principle, design and control methods, main benefits and limitations as well as current industrial applications. Cyclic distillation can be rather easily implemented in existing columns by simply changing the internals and the operating mode, thus bringing new life to old distillation towers by significantly increasing the column throughput, reducing the energy requirements and offering better separation performance. © 2016 Society of Chemical Industry     

Minimum reflux calculation for multicomponent distillation in multi-feed,multi-product columns: Mathematical model

Multi-feed, multi-product distillation columns are ubiquitous in multicomponent distillation systems. The minimum reflux ratio of a distillation column is directly related to its energy consumption and capital cost. Thus, it is a key parameter for distillation systems design, operation, and comparison. In this series, we present the first accurate shortcut based algorithmic method to determine the minimum reflux condition for any general multi-feed, multi-product (MFMP) distillation column separating any ideal multicomponent mixture. The classic McCabe-Thiele or Underwood method is a special case of this general approach. Compared with existing techniques, this method does not involve any rigorous tray-by-tray calculation, nor does it require guessing of key components. In this first part of the series, we present the mathematical model for a general MFMP column, derive constraints for feasible separation and minimum reflux condition, discuss their geometric interpretations, and present an illustrative example to demonstrate the effectiveness of our approach.     

Global optimization of multicomponent distillation configurations: 2. Enumeration based global minimization algorithm

We present a general Global Minimization Algorithm (GMA) to identify basic or thermally coupled distillation configurations that require the least vapor duty under minimum reflux conditions for separating any ideal or near‐ideal multicomponent mixture into a desired number of product streams. In this algorithm, global optimality is guaranteed by modeling the system using Underwood equations and reformulating the resulting constraints to bilinear inequalities. The speed of convergence to the globally optimal solution is increased by using appropriate feasibility and optimality based variable‐range reduction techniques and by developing valid inequalities. The GMA can be coupled with already developed techniques that enumerate basic and thermally coupled distillation configurations, to provide for the first time, a global optimization based rank‐list of distillation configurations. © 2016 American Institute of Chemical Engineers AIChE J, 62: 2071–2086, 2016     

乙烯生产中精馏塔的先进控制

阐述乙烯生产中采用常规反馈控制附加约束性控制、前馈控制、组分控制等技术的精馏塔先进控制。     

邻苯基苯酚的工业化生产工艺

邻苯基苯酚的工业化生产工艺以环己酮为原料,在酸性催化剂作用下进行缩聚反应,反应过程中经带水剂脱水,得到二聚中间体2-(1-环己烯基)环己酮和2-环己亚烷基环己酮的混合物,采用高效精馏技术对二聚中间体进行分离提纯,并回收未完全反应的环己酮。提纯后的二聚体以氢气作为载气,进入固定床反应器进行催化脱氢反应,反应得到的产物经过高效精馏、重结晶、干燥及切片等单元操作,最终可以得到质量分数大于99.5%的成品邻苯基苯酚。