ASPEN: An Advanced System for Process Engineering

The paper presents an overview of ASPEN (Advanced System for Process Engineering) which is a next-generation process simulator and economic evaluation system. The system is presently under development for use in engineering of fossil energy conversion processes.     

Betriebsleittechnik – Funktionsumfang und Stand der Systeme

Process Control Engineering – Function and State of the Art of the Systems On considering material flow in a chemical engineering company it is possible to identify associated business processes whose support by appropriate information processing systems will permit efficient control of material flow and material conversion as production goal. Such consideration indicates not only the principal functions of information processing but also the necessary integration of process-oriented information systems such as those relating to formulation, production planning, and operating data processing. Various concepts are currently under discussion for such integration.     

EDV-gestützte wissensbasierte Prozeßsynthese

Computer-aided knowledge-based process synthesis. Process synthesis as a branch of process development serves to structure chemical processes. Since it is largely influenced by trial-and-error knowledge, knowledge-based programming resulting from AI research (Prolog, LISP, Shells) opens up new possibilities compared to conventional procedural systems (Fortran, PL/1). The immense area of knowledge of process synthesis soon requires subdivisions into smaller knowledge domains for which expert systems first arise as island solutions, which subsequently combine as cooperating distributed expert systems. A possible procedure is illustrated for the knowledge based process synthesis program PROSYN /REXPERT PLUS .     

Model-based fault diagnosis for hybrid systems: Application on chemical processes

The complexity and the size of the industrial chemical processes induce the monitoring of a growing number of process variables. Their knowledge is generally based on the measurements of system variables and on the physico-chemical models of the process. Nevertheless, this information is imprecise because of process and measurement noise. So, the research ways aim at developing new and more powerful techniques for the detection of process fault. This article presents a method for the fault detection based on the comparison between the reference model evolution and the real system generated by the extended Kalman filter. The reference model is simulated by the dynamic hybrid simulator, PrODHyS. It is a general object-oriented environment which provides common and reusable components designed for the development and the management of dynamic simulation of industrial systems. The use of this method is illustrated through a didactic example relating to the field of Chemical Process System Engineering.     

Flow-Sheeting-Programme für die Prozeßsimulation

Flowsheeting systems for process simulation. Simulation of process plants with flowsheeting systems has been state of the art in chemical plant design and in the chemical industry for many years. Modern computers now permit steady state simulation of complex chemical plants with sufficient accuracy. This paper outlines the different approaches to steady state process simulation, names the advantages and disadvantages, and gives an outlook on further developments. Process optimization, process integration, and process synthesis will be discussed. The integration of different programs, e.g. the connection between flowsheeting systems and computer-aided design (CAD) will be described. An advance in user friendliness will be reached by latest developments in the field of personal computers and workstations and by database management systems.     

Verfahrensentwicklung durch Kombination von Prozeßsimulation und Miniplant-Technik

Efficient Process Development by Combining Process Simulation and Miniplant Technique . International competition, growing ever fiercer, and product life cycles which are becoming shorter all the time demand a significant contraction times from the chemical industry, of the implementation times from the conception of a product to its market introduction. A significant contribution to rapid and cost-effective detailed planning of a new production process is provided by the combination of process simulation and an experimental technique developed within BASF AG, i.e. the ?miniplant”? technique. This article starts by demonstrating the importance of process simulation in the individual phases of process development. It explains the characteristic features of the miniplant technique, what objectives are pursued by employing his technique, and what advantages ccan be achieved, compared with setting up and operating pilot plants. Finally, two examples illustrate that it is possible, by combining process simulation and miniplant technique, to develop processes more rapidely and to scale them up directly from the laboratory to production level.     

Lipasekatalysierte Triglyceridumesterung in einem lösungsmittelfreien Prozeß II: Verfahrenstechnische Parameter des kontinuierlichen Prozesses

Lipase-Catalyzed Interesterification of Triglycerides in a Solvent-Free Process II: Engineering Parameters for the Application of a Continuous Process Fixed bed reactors are promising reactor systems for the continuous interesterification of fats and oils with immobilized lipases in a solvent-free process. Engineering parameters which are necessary for the design of the bioreactor were studied. The kinetics of the interesterification in the continuous process are influenced by the washing out of water from the biocatalyst by the substrate. External mass transfer effects can be neglected, internal mass transfer reduces the reaction rate. The pressure drop across the catalyst bed is acceptable at temperatures higher than 60°C. The results show that the continuous interesterification in a solvent-free process can be performed.     

Von der Prozeßsimulation zur Lebenszyklusmodellierung

From Process Simulation to Lifecycle Modeling Process simulation is an established technology to support the design and operation of chemical processes. Since this technology has reached a mature state, an obvious question concerns emerging technologies which may succeed process simulation in the future. This contribution attempts to answer this question. The increasing capabilities of mathematical modeling and simulation on various levels of detail increasingly ask for the integration of available but independently developed and applied technologies across the process design lifecycle. Novel computer-based design support environments are required for this purpose. Such environments need to integrate existing modeling and simulation tools in a workflow oriented manner in order to provide context specific support during the whole design process.     

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。     

A tribute to professor Roger Sargent: Intellectual leader of process systems engineering

This article and this issue of the AIChE Journal, is a tribute to Professor Roger Sargent who, as pioneer and intellectual leader of process systems engineering, has had a profound impact on the discipline of chemical engineering. Spanning more than five decades, his work has provided a strong mathematical foundation to process systems engineering through the development of sophisticated mathematical and computational tools for the simulation, design, control, operation and optimization of chemical processes. In this article we first give a brief overview of his career that included several leadership positions and the establishment of the Centre for Process Systems Engineering (CPSE) at Imperial College London. We next review his research contributions in the areas of process modeling, differential algebraic systems, process dynamics and control, nonlinear optimization and optimal control, design under uncertainty, and process scheduling. We highlight the tremendous impact that he has had through his students, students' students, and his entire academic family tree, which at present contains over 2000 names, probably one of the largest among the academic leaders of chemical engineering. Finally, we provide a brief overview of him as a modest and charming individual with a wonderful sense of humor. He is without doubt a true intellectual giant who has helped to expand the scope of chemical engineering by providing a strong systems component to it, and by establishing strong multidisciplinary links with other fields. © 2016 American Institute of Chemical Engineers AIChE J, 62: 2951–2958, 2016     

Anlagensicherung mit Mitteln der Prozeßleittechnik

Plant Securing by Means of the Process Control Engineering. The Process control engineering contributes in an important way to the environmental protection and to the plant security in the chemical industry. Due to their historical evolution and the different forms of organization the enterprises have different, but equivalent safety conceptions by process control engineering. These different procedures have been synchronized and the results have been formulated in a NAMUR recommendation. The contribution gives an information about the most important results of this work.     

工程硕士过程系统工程课程建设与探索

过程系统工程是华东理工大学化学工程领域工程硕士的必修课程。我们通过课程教改,加强了工程硕士对基本理论的理解,注重案例教学、理论与实践相结合,取得了良好的教学效果。     

Prozeßentwicklung: Von der Exergieanalyse bis zur EDV-gestützten Optimierung

Process development: From exergy analysis to computer-aided optimisation. In processes in which chemical compositions or states are altered, limiting case analyses based on the first and second laws of thermodynamics are often of use during preliminary process analyses. Since the introduction of computers for process calculations exergy analyses can be carried out in a simple way and weak points in initial designs in the sense of the second law conveniently located. It is also possible to use exergy analyses to make product predictions if transferable practical exergy losses are available from past experience. In low temperature and energy technology the use of suitably defined efficiencies have been of use for many years in eliminating less attractive processing routes and thus reducing the number of possible designs to be investigated. For many decades so-called ?Sum Q/T Diagrams”? have been used in low temperature processing to visualize and improve temperature profiles in heat exchanger networks. Recently technology has been further developed into ?Pinch Technology”?. At the end of process development comes the final detailed optimization. The expensive and time consuming sequential way of working used in the past is being gradually replaced today with equation-oriented simulation and optimization tools such as the OPTISIM program. Expert systems, in principal, offer the chance of supporting the chemical engineer during the initial design of complete and complex processes. However, the experience with such systems to date has shown that a practical solution lies a long way into the future.     

Heuristisch-numerisches Beratungssystem für die Reaktorauswahl bei der Verfahrensplanung

A Heuristic-Numerical Advisory System for the Choice of Reactors in Process Design. Since it has become apparent that neither expert systems nor numerical calculations alone satisfy requirements placed on them in the search for the most suitable industrial reactor, a new type of system, viz. the heuristic-numerical advisory system, was developed. It utilises both knowledge-based techniques (production rules and/or frames) and the wide range of calculation tools available in chemical reaction engineering, which are addressed via interfaces. In this way it has become possible to obtain very early reliable information about the later design of an appropriate industrial reactor.     

Plant-specific dynamic failure assessment using Bayesian theory

Abnormal events of varying magnitudes result in incipient faults, near-misses, incidents, and accidents in chemical plants. Their detection and diagnosis has been an active area of research [Venkatasubramanian, V., Rengaswamy, R., Kavuri, S.N., 2003a. A review of process fault detection and diagnosis, Part II: Quantitative model and search strategies. Computers and Chemical Engineering 27(3), 313-326; Venkatasubramanian, V., Rengaswamy, R., Kavuri, S.N., Yin, K., 2003b. A review of process fault detection and diagnosis, Part III: Process history based methods. Computers and Chemical Engineering 27(3), 327-346]. However, estimation of the failure probabilities of safety systems to predict these consequences (end-states), has received little attention in the CPI. In this work, methods for plant-specific, dynamic risk assessment are developed to predict the frequencies of abnormal events utilizing accident precursor data, helping to achieve inherently safer operations. These methods, which involve repetitive risk analysis after abnormal events occur, are especially beneficial for operations involving complex nonlinearities and multi-component interactions. Herein, the failure probabilities of safety systems and end-states are estimated using copulas and Bayesian analysis to ensure better predictions. The joint probability distribution for the failure probability of a safety system(s) having different consequences is modeled using the Cuadras and Auges copula [Nelsen, R.B., 1999. An Introduction to Copulas. Lecture Notes in Statistics, Springer, New York]. Accident precursor data are used to modify dynamically the initial estimates of failure probabilities to obtain posterior failure probabilities of the safety systems of an exothermic reactor. Finally, fuzzy memberships to various critical zones are formulated as a function of end-state probabilities to judge the safety status of a chemical plant.     

过程控制工程创新实践教育模式建设研讨

我们根据过程控制工程课程具有综合性、实践性强的特点,以"聆听→质疑→解惑→实践"的教学方法,通过采用多模式地运用现代化教学手段,创建课内、课外多形式的实践能力培养模式,形成了兴趣驱动与问题探索的素质教育培养模式,推进了质疑重于聆听,反思高于理解的工程教育改革模式。基于化工过程常用典型装置特性和控制系统设计要求,我们构建了一套完善的多层次过程控制工程实践教学仿真实验系统,切实提高学生的工程实践能力。     

Planungsansatz für modulare Anlagen in der chemischen Industrie

Modularly built production plants are considered for planning new chemical plants, in case they shall be designed quickly and transformable, flexible plants are required. To date, these plants are planned mostly by the conventional planning process, so that time saving is not achieved. This paper presents a module based planning approach, which allows a structured planning of new modular plants in a time‐efficient way. All required documents for building modules are stored in the Process Equipment Design documentation, which is available for re‐use in future projects.     

20 Years of Schnapps in Educating Chemical‐Engineering Students

In the so‐called Branntwein AG chemical‐engineering bachelor students first produce wine from a chosen type of fruit, which is then distilled twice to arrive at schnapps as the final product. Before performing the process, the required steps are designed based on an adequate mathematical representation. Besides these engineering skills, soft skills are practiced like team work, project management, and budget planning. During meanwhile 20 Branntwein AGs this course has proven to be an excellent means to inspire chemical‐engineering students and also to promote chemical engineering to the public.     

过程控制工程课程教学体系的优化

结合现代社会对过程控制工程技术人员的需求与现有自动化专业课程的设置,我们改进了过程控制工程课程的教学目标与相应的教学内容,并进一步优化了课程的教学体系,强化了控制系统设计与综合应用实施等教学环节。近年来的实际教学效果充分体现了该教学体系的完整性与先进性,对培养自动化专业人才的创新能力与实践能力作用显著。     

Mathematical modelling of structure formation during combustion synthesis of advanced materials

The synthesis of advanced materials by a wave of heterogeneous combustion propagating through a charge mixture, or the so-called self-propagating high-temperature synthesis (SHS) has many potential advantages over conventional techniques of synthesis. Because of high heating rates, steep temperature and concentration gradients, and fast accomplishment of reactions, the mechanisms of physical, chemical and structural transformations in the SHS wave are intricate and often not known. Further understanding of interaction mechanisms in SHS waves, relating the process parameters to structure and properties of the target material, and the application of SHS to producing final articles necessitates developing mathematical models for SHS-related phenomena.Various aspects of mathematical modelling of SHS are discussed in this paper. They include the analysis of novel factors influencing the structure formation, viz. the heating-to-reaction and mass transfer-to-reaction time ratios, autocatalysis and intrinsic stochasticity, which are unnoticed in traditional synthesis methods. The application of chemical thermodynamics and combustion theory to modelling SHS processes is outlined. Novel mathematical models are developed for SHS on condensed systems, which involve stochastic effects and autocatalysis. New models for solid-gas systems are worked out, which include the reaction kinetics and mass transfer of a gaseous reactant and permit predicting the structure formation pattern in the SHS wave. Application of mathematical modelling to producing porous final articles by means of SHS is discussed.