基于流程模拟软件平台的化工计算教材编写

为了适应化工流程模拟软件应用日益普及的现状,我们编写了以强化训练学生计算能力为目标的《化工计算与软件应用》教材。本文分析了传统化工计算教材内容的不足,阐明了选用流程模拟软件作为化工计算主要工具的必要性,介绍了新教材编写过程中内容组织、章节安排、编写风格的考虑,对新教材教学方式的变革提出了意见。本教材在校内使用两年来效果明显,学生应用化工流程模拟软件进行工艺设计的能力大幅增强。     

Aspen one v7在分离工程教学中的应用

分离工程是化工类专业重要专业课,是一门实践性非常强的课程。各种平衡分离过程的计算既是教学的重点,又是教学的难点。随着电脑在学生中普及率的提高,为使用模拟软件进行辅助教学提供了条件。使用aspen one v7的aspen properties模块和aspen plus模块辅助教学,学生在aspen properties中完成物性参数计算、逸度系数、活度系数、平衡常数计算、泡露点计算等分离工程基础数据计算,同时熟悉aspen one软件的使用,为后续在aspen plus中完成单级平衡分离计算、精馏吸收严格计算打下基础。同时,在分离工程教学过程中引入aspen one的应用,为后续课程"化工过程模拟"的教学打下基础,收到较好的教学效果。     

Aspen plus在化工过程分析与合成课程教学中的应用

化工过程分析与合成是化工类实践性非常强的专业基础课,精馏塔的实践教学是教学的重点和难点。文章采用Aspen Plus软件,以甲醇制二甲醚的实际工艺为案例,对二甲醚精馏塔进行模拟、分析,同时使学生熟悉Aspen Plus软件的使用,为后续化工设计打下基础。     

金属配合物与核酸作用机理的理论计算

通过计算机模拟金属配合物与核酸作用机理,对其理论模型能量计算和结构优化。在不同的化学环境条件下得到不同的实验模拟结果,对真实的化学反应过程有重要的指导意义和参考意义。通过Gaussian03,Gauss View等软件的结合应用,分别应用于优化计算和理论建模,熟悉了对化学软件操作应用。     

石油化工流程模拟软件现状与发展趋势

流程模拟软件是石油化工行业的核心研发设计软件,其应用已贯穿于技术研发、工程设计、生产优化等全生命周期业务环节。我国石油化工行业使用的商业流程模拟软件90%为国外产品,基本被国外垄断。本文从商业软件的角度,首先对化工流程模拟技术和早期的软件发展进行了回顾,分析了近年来跨国流程工业巨头收购兼并案例和启示。在对石油化工企业和软件供应商调研的基础上,分析了国内流程模拟软件的市场应用情况和自主流程模拟软件的成熟度,阐述了流程模拟软件技术发展的五大趋势：遵循CAPE-OPEN软件接口规范、基于分子级表征和反应动力学建模、数据驱动与工艺机理联合建模、三大集成建模和数字孪生应用等。石化产业需求和市场规模以及科研基础是发展自主流程模拟软件的有利条件,但构建工业软件政产学研用产业生态链,形成产品化和市场化为导向的健康产业环境尤为关键。     

利用Aspen Plus 7.3进行严格精馏过程模拟

化工过程模拟是通过计算机对化工生产过程的再现,由于计算量大,必须通过相应的化工模拟软件来实现。Aspen Plus,尤其是Aspen Plus 7.3,由于其计算精确、运行速度快,成为化工设计者的首选软件。本文通过介绍利用Aspen Plus 7.3进行严格精馏模拟,说明了严格精馏模拟的应用范围以及利用Aspen Plus 7.3进行严格精馏模拟的方法。     

Aspen Plus 7.3在化工设计中的应用

由于化工设计计算量大,必须通过相应的化工模拟软件来实现。Aspen Plus 7.3计算精确,运行速度快,成为化工设计者的首选软件。通过介绍利用Aspen Plus 7.3进行闪蒸条件的确定,说明利用计算机进行化工设计的步骤和方法。     

Optimization of a multiphase sensor for detection of phosphonates in air

The objective of this article is to report the modeling and optimization of a new MEMS‐based phosphonate sensor that utilizes a porous membrane between a gas and a liquid stream to allow operation at low‐liquid and high‐gas flow rates. Previous work from our laboratory demonstrated that phosphonate molecules can be detected with such a device, but the sensitivity was insufficient for certain applications (e.g., detection of pesticides in foodstuffs). In this article, COMSOL simulations and design of experiments were used to optimize the device. We find that both the simulation and the experiment show that (i) the size of the pores in the membranes and (ii) the liquid channel height make the most difference to the sensor response. Also, by optimizing the geometry, the sensitivity of the device could be enhanced. The optimized device can detect 10⁹ molecules with good signal to noise. © 2009 American Institute of Chemical Engineers AIChE J, 2010     

Implementation of the waste reduction (WAR) algorithm utilizing flowsheet monitoring

Environmental metric software can be used to evaluate the sustainability of a chemical based upon data from the chemical process used to manufacture it. An obstacle to the development of environmental metric software for use in chemical process modeling software has been the inability to obtain information about the process directly from the model. There have been past attempts to develop environmental metrics that make use of the process models, but there has not been an integrated, standardized approach to obtaining the process information required for calculating metrics. As a result, environmental evaluation packages are largely limited to use in a single simulation package, further limiting the development and adoption of these tools.This paper proposes a standardized mechanism for obtaining process information directly from a process model using a strongly integrated interface set, called flowsheet monitoring. The flowsheet monitoring interface provides read-only access to the unit operation and streams within the process model, and can be used to obtain the material flow data from the process streams. This material flow data can then be used to calculate process-based environmental metrics. The flowsheet monitoring interface has been proposed as an extension of the CAPE-OPEN chemical process simulation interface set.To demonstrate the capability of the flowsheet monitoring interfaces, the US Environmental Protection Agency (USEPA) WAste Reduction (WAR) algorithm is demonstrated in AmsterCHEM's COFE (CAPE-OPEN Flowsheeting Environment). The WAR add-in accesses the material flows and unit operations directly from the process simulator and uses flow data to calculate the potential environmental impact (PEI) score for the process. The WAR algorithm add-in is included in the latest release of COCO Simulation Environment, available from http://www.cocosimulator.org/.     

Aspen Plus在化工原理课程设计教学中的应用

Aspen Plus是一款大型商业过程模拟软件，文章结合了多年的化工原理课程设计教学经验，介绍了如何将流程模拟软件Aspen Plus运用到化工原理课程设计环节中。实践经验表明，过程模拟软件的应用不仅可以培养学生的兴趣，提高设计效率和质量，增强学生的工程意识，同时也能拓宽教师的选题范围，使课程设计更接近工程实际，更有利于教学与实践的结合。     

联醇工艺中能量利用的探讨

采用管壳式合成反应器和C207催化剂,建立了联醇合成工艺模型,并借助稳态模拟计算软件对联醇合成工艺系统进行过程模拟。利用化工稳态软件,对具有不同位置废热锅炉的合成工艺系统的流程合理性、能源利用效率和有效能效率进行了分析和计算,使联醇合成工艺在能量利用方面得到了初步优化。     

Computational study on reaction enthalpies of urethane‐forming reactions

Computational calculations were performed on urethane‐forming reactions using Gaussian 09 software (i.e. molecular modeling) toward the goal of providing thermodynamic parameters. Total electronic and thermal enthalpies and zero‐point vibrational energies of reactants and products were computed by the software and then reaction enthalpies were calculated based on these results. The location of functional groups has the most significant impact on reaction enthalpies while molecular size, chain length and solvent effect have relatively less impact on reaction enthalpies. By comparison to new experimental studies and values reported in literature, better‐informed recommendations on which values of reaction enthalpies to use for urethane foam process simulation were provided. The utility of computational chemistry results succeeded in being an enabling technology to improve foam process simulation. In turn, simulation of urethane‐forming reactions is useful to bridge the gap between fundamental computational chemistry calculations and practical applications. POLYM. ENG. SCI., 55:1420–1428, 2015. © 2015 Society of Plastics Engineers     

A new superstructure optimization paradigm for process synthesis with product distribution optimization: Application to an integrated shale gas processing and chemical manufacturing process

We propose a novel process synthesis framework that combines product distribution optimization of chemical reactions and superstructure optimization of the process flowsheet. A superstructure with a set of technology/process alternatives is first developed. Next, the product distributions of the involved chemical reactions are optimized to maximize the profits of the effluent products. Extensive process simulations are then performed to collect high‐fidelity process data tailored to the optimal product distributions. Based on the simulation results, a superstructure optimization model is formulated as a mixed‐integer nonlinear program (MINLP) to determine the optimal process design. A tailored global optimization algorithm is used to efficiently solve the large‐scale nonconvex MINLP problem. The resulting optimal process design is further validated by a whole‐process simulation. The proposed framework is applied to a comprehensive superstructure of an integrated shale gas processing and chemical manufacturing process, which involves steam cracking of ethane, propane, n‐butane, and i‐butane. © 2017 American Institute of Chemical Engineers AIChE J, 63: 123–143, 2018     

Experimental validation of a flexible modeling approach for distillation columns with packings

The two main concepts for the modeling of distillation columns are the equilibrium‐stage (EQ) and the nonequilibrium‐stage (NEQ). A model is presented which combines decisive features of both conventional concepts. Based on the idea of a reduced nonequilibrium‐stage (RNEQ), this model can be used for the simulation of distillation columns with packings. In contrast to the conventional NEQ approach, this model neglects the influence of liquid side mass‐transfer coefficients, which ultimately allows to come up with only one empirical equation describing the overall mass transfer. Thus, a considerable reduction in model complexity is reached, which allows for an efficient consideration of new experimental distillation results. Fitted to experimental data, the model is able to predict, how different pressures and chemical systems might affect the separation efficiency. By comparing calculation results with experimentally determined separation efficiencies for three different packing types, these valuable RNEQ qualities are illustrated. © 2014 American Institute of Chemical Engineers AIChE J, 60: 3833–3847, 2014     

Modeling of a continuous rotary reactor for carbon nanotube synthesis by catalytic chemical vapor deposition

The modeling of carbon nanotube production by the CCVD process in a continuous rotary reactor with mobile bed was performed according to a rigorous chemical reaction engineering approach. The geometric, hydrodynamic, physical and physicochemical factors governing the process were analyzed in order to establish the reactor equations. While the study of the hydrodynamic factor suggests a co‐current plug‐flow approximation, the physical factor mainly deals with the phenomena of transport and the transfer of mass, which can be neglected. Concerning the physicochemical factor, the modeling is based on knowledge of the expression of the initial reaction rate, and takes into account catalytic deactivation as a function of time, according to a sigmoid decreasing law. The reactor modeling allows obtaining the evolution of partial pressure, carbon nanotube production and catalytic deactivation along the reactor for given initial operating conditions. The comparison between experimental and calculated production highlights a very good fit of data. © 2009 American Institute of Chemical Engineers AIChE J, 2009     

Kriging meta‐model assisted calibration of computational fluid dynamics models

Computational fluid dynamics (CFD) is a simulation technique widely used in chemical and process engineering applications. However, computation has become a bottleneck when calibration of CFD models with experimental data (also known as model parameter estimation) is needed. In this research, the kriging meta‐modeling approach (also termed Gaussian process) was coupled with expected improvement (EI) to address this challenge. A new EI measure was developed for the sum of squared errors (SSE) which conforms to a generalized chi‐square distribution and hence existing normal distribution‐based EI measures are not applicable. The new EI measure is to suggest the CFD model parameter to simulate with, hence minimizing SSE and improving match between simulation and experiments. The usefulness of the developed method was demonstrated through a case study of a single‐phase flow in both a straight‐type and a convergent‐divergent‐type annular jet pump, where a single model parameter was calibrated with experimental data. © 2016 American Institute of Chemical Engineers AIChE J, 62: 4308–4320, 2016     

Investigation of chitosan gelation mechanisms by a modeling approach coupled to local experimental measurement

The formation of chitosan hydrogels using experimental and modeling approaches are described. Chitosan gelation was induced by an ammonia intake from a liquid phase (wet process) or a gaseous phase (vapor process), involving three steps: (i) external mass transfer at the interface, (ii) internal transport within the polymer solution, and (iii) chemical reactions inducing gelation. The experimental study allowed quantifying gelation fronts speeds from local measurement. The main resistance to gelation was investigated for both gelation processes. Experimental results exhibited that internal diffusion through the chitosan matrix was the main resistance in the whole gelation mechanism. The numerical model involved a coupling between mass and heat transfer phenomena and chemical reactions, in transient conditions. Numerical results were first validated and then used as a predictive tool to investigate (i) coupled mechanisms localized in the chitosan matrix and (ii) the influence of operating conditions on gelation rates. © 2011 American Institute of Chemical Engineers AIChE J, 2012     

尿素工艺冷凝液回收过程的模拟与分析

应用化工模拟软件PROII对尿素工艺冷凝液水解流程进行模拟,并通过模拟计算对原流程装置提出两塔合一的改造建议。相比原流程,新流程不仅可以达到尿素水解的工艺指标要求,而且具有占地面积小,流程短,操作简单,设备投资少,能耗低等优点。     

Cambridge weblabs: A process control system using industrial standard SIMATIC PCS 7

Continually assessed project work forms a core part of the Chemical Engineering curriculum at Cambridge. We have designed and built a remotely controlled chemical reactor that has been used and evaluated in undergraduate chemical engineering education. The purpose was to provide a pedagogical and authentic experience to students with essential training when laboratory usage was impossible or impractical, and be able to run and share the experiments as a fully functioning chemical engineering plant. A state-of-the-art SIMATIC PCS 7 Process Control System from Siemens is used for controlling, monitoring and providing results output. We describe the experimental setup, the hard- and software used, the teaching assignment and finally the results of the student evaluation. We also describe the challenges on the sustainability of the weblabs.     

Chemical Engineering Education in the Next Century

This paper summarizes the work of the EFCE Working Party Education (WPE) over the last decade and attempts to identify effective educational solutions to meet the challenges caused by the rapid rate of change in technology and society world‐wide. The paper uses the results of the 1994 WPE survey of curricula in European Chemical Engineering Universities to identify a first degree level core curriculum. The problem of how to adapt the discipline to meet technological and societal changes without losing its identity is addressed. Basic sciences, chemical engineering science, integrated systems design and holistic thinking are emphasized as essential elements of the discipline. The paper discusses how Safety, Health and Environment (SHE), biotechnology, computerized models, product design, sustainability and other new subjects have been incorporated into chemical engineering curricula since the original survey. A simple model of the education process is presented to indicate how students might obtain a chemical engineering understanding and mindset. The paper explains how chemical engineering evolved from its origins in the petrochemical, heavy chemical and nuclear industries, to its current wide range of applications in industries, such as fine chemicals, food, pharmaceuticals, software, and cybernetics. It is suggested that the impact of changes arising from industry, new technology and society has driven the chemical engineering discipline to a point where it is now ripe for re‐invention. The effects of rapid industrial, technological and societal change on chemical engineering education are studied against the backdrop of a discipline on the threshold of a significant change. The paper concludes by identifying curriculum development, personal development and life‐long learning as three important factors for educating chemical engineers for a successful future.