SIMOP: Efficient reactive distillation optimization using stochastic optimizers

A methodology to improve the efficiency of stochastic methods applied to the optimization of chemical processes with a large number of equality constraints is presented. The methodology is based on two steps: (a) the optimization of the simulation step, which involves the optimum choice of design variables and subsystems to be simultaneously solved; (b) the optimization of the nonlinear programming (NLP) problem using stochastic methods. For the first step a flexible tool (SIMOP) is used, whereby different numerical procedures can be easily obtained, taking into account the problem formulation and specific characteristics, the need for specific initialization schemes and the efficient solution of systems of nonlinear equations. This methodology was applied to the optimization of a reactive distillation process for the production of ethylene glycol. Due to the complexity of the mathematical model, several different numerical procedures were generated, and their influence on the computational burden and on the reliability and accuracy of the optimization to reach the global optimum were studied. The results obtained suggest that in addition to the choice of design variables, the structure of subsystems associated to numerical procedures has a considerable impact on the performance of the optimizers.     

色谱纯甲醇的制备研究

随着液相色谱的广泛应用，作为反向液相色谱流动相的色谱纯甲醇的需求量与日俱增，产品供不应求。但色谱纯甲醇要求纯度很高，且在紫外波段(220～280nm)内需很高的透光率。这给色谱纯甲醇的制备增添了很大困难。因而，色谱纯甲醇价格较高，目前东北三省尚无生产厂家，主要依靠外省或国外进口。如何由工业级甲醇制备色谱纯甲醇是本研究的主要课题，实验原理是通过测定影响透气率的主要因素，再通过2．4-二硝基苯肼除去醛、酮，再用浓碱溶液中和羧酸、皂化酯类，再进行精馏，从而获得满意的结果。     

能流结构图式分析法在丙烯热泵精馏工艺中的应用

提出了一种图式热力学分析新工具－能流结构图，并力图以此为基础，形成一种称之为能流结构图式热力学分析的新方法。该法采用图形方式将技术能量系统的用能特征可视化，使人们便于分析处理大量，复杂的信息，便于把握系统特性，进而完成系统的能量分析与集成，提出创新的节能方案。以该方法在2万t/a的丙烯精馏工艺中的应用为例，证明了新方法的实用性和有效性。     

八碳烯分离工艺的研究

从能量综合集成的角度提出了八碳烯精馏分离工艺 ,对所提流程进行了优化模拟计算及分析 ,为八碳烯分离工艺的施工设计提供了充分的依据。投产情况表明 ,该研究改变了八碳烯的生产现状 ,使得八碳烯生产的经济效益显著提高     

外消旋螺环二酮的合成工艺条件研究

详细研究了以己二酸、溴代丁酸乙酯为原料，采用简便高效的方法制备外消旋螺环二酮的最佳条件和有关工艺。     

煤制合成气低温甲醇洗配管总结

本文根据以煤为原料的合成氨工艺装置中低温甲醇洗涤净化系统的特点，对其配管在工程设计时的一些特殊要求进行总结，供工程设计人员参考。     

DCS控制系统在粗苯蒸馏工艺中的应用

针对传统粗苯蒸馏工艺人工调节频繁,调节不及时、不准确,产品质量不稳定,劳动负荷大等问题,通过引入DCS控制系统,建立计算机自动调节模型,调整函数的微分和积分变量实现脱苯塔塔顶回流量、进再生塔的蒸汽量和管式加热炉富油出口温度的自动控制,从而实现粗苯生产工艺的稳定、高产、优质和低耗。     

甲缩醛反应精馏过程模拟

通过实验取得了甲醛和甲醇合成甲缩醛的反应参数;建立了其连续生产工艺的数学模型,利用ASPEN PLUS软件对甲醛和甲醇缩合生成甲缩醛进行了模拟,结果表明反应精馏连续生产甲缩醛的工艺是可行的,转化率高达99%,并得到含甲缩醛99%的产物,同时确定了进料板和反应区.     

ALKYD PAINT WASTE CHARACTERIZATION AND DISTILLATION

In the present study the characterization and distillation of alkyd paint waste have been carried out in order to establish the technical viability of organic solvents recovery and to decide upon the best environmental management for the waste stream from a paint spray-booth application in an automotive component factory. The paint is a black primer based on an alkyd resin with toluene and xylene as solvents, black carbon as pigment, fillers, and other minor components.

The paint, paint wastes, and distillation wastes have been characterized by determination of the physicochemical properties of the solid (solvents content and flash point) and determination of ecotoxicity (EC₅₀), total organic carbon (TOC), and metals concentration of the leachates. The highly volatile matter (HVM) content, determined by the weight loss at 200°C, has been used as a parameter to relate with the hazardous wastes regulations based on the characterization parameters EC₅₀, TOC, and flash point.

Distillation experiments have been performed in a simple batch mode with mixtures of paint waste, water, and additives in order to obtain high efficiencies in the recovery of volatile organic compounds and to obtain a final solid with nonhazardous behavior and good manageability qualities. A fractional factorial design (2^3-1) of experiments was carried out in order to study the influence of the distillation variables: water/paint waste ratio (2/1-3/1 (g/g)), temperature (110°-145°C), alkaline additives (Na(OH),CaO, Ca(OH)₂), and amount of other additives (wt.% of bentonite, cement, and Ca(OH)₂) on the solvent recovery, [% VOCs]_Recovery, on the residual volatile organic compounds, [% VOCs]_{Distillation Waste}, and on the total organic content (TOC) of the waste leachates. The present work shows the quantitative results of the alkyd paint waste distillation process under optimum conditions.     

Fatty acid esterification by reactive distillation: Part 2—kinetics-based design for sulphated zirconia catalysts

In a previous study on the basis of reaction equilibrium, it was demonstrated that the synthesis of fatty acids esters of heavy alcohols by catalytic reactive distillation (RD) is basically feasible. Presently, the analysis is expanded to the kinetics-based design applied to the synthesis of 2-ethylhexyl dodecanoate. Experimental data for a super-acidic sulphated zirconia catalyst are employed. It is shown that this catalyst is highly selective even for the high alcohol/acid ratios as prevail in a RD column. To avoid catalyst deactivation, liquid-liquid segregation into an organic and an aqueous phase must be prevented, and operating temperatures beyond must be chosen. A kinetic model based on liquid activities is proposed, with parameters determined from both kinetic and equilibrium measurements. A typical column design has 13 reactive stages with a catalyst loading of , temperature profile of 400-, and a space velocity of for 99.9% purity product ester. A modified Damköhler number is proposed.