Prozeßführung

Process Management The concept of “process management” is being increasingly used as a complement to similar concepts such as process automation, process control, etc. Such terms are defined within a framework of more general conceptional trends, which can be characterised by terms such as integration and holistic. Considerable potential exists with this framework for fruitful joint development of the main disciplines contributing to process management, viz. process engineering and automation engineering. Such developments remain inaccessible to the individual disciplines. The present article considers this concept from an industrial viewpoint.     

Instationäre Reaktionsführung zur Modellierung heterogen katalytischer Reaktionen

Transient processes in modelling heterogeneous catalytic kinetics. It is often difficult to obtain mathematical models to describe the dynamics of heterogeneous catalytic reactors. Kinetics determined under steady-state conditions are normally not valid for the transient behaviour of catalytic reactions. In order to find valid kinetic models, information is needed about the adsorption-desorption processes and the formation of intermediates on the surface. To get single step models, experiments have to be carried out under transient or oscillatory conditions. This is discussed for different examples taken from the literature.     

Prozeßführung und Verfahrenstechnik zur schadstoffarmen Verbrennung von Abfällen

Process control and engineering of essentially pollutant-free combustion of wastes. The avoidance, reduction, and utilization of wastes are recognized as exploitable strategies. In spite of these measures, in the future wastes remain which still require treatment. Combustion is possible way substantially converting complex chemical compounds in an environmentally compatible manner. The present paper deals in a general manner with the possibilities of influencing combustion control (primary measures) for wastes in order to obtain minimum levels of pollutants. A difference is made between gaseous, liquid, or powdered wastes and those comprising mixtures of coarse, pasty, and liquid components. The paper deals with mixing mechanisms, temperature control, burn out, pollutant limitation, and the resulting fundamental possibilities of process control and engineering.     

Prozeßführung zur Sicherung reproduzierbarer Qualität in der verfahrenstechnischen Produktion

Process engineering to assure reproducible quality in production. This paper presents an hierarchically structured process control concept in which product quality is regarded as the central orientation factor. The application of control engineering methods is intended to assure maintenance of the product quality specifications. The second part of the article briefly considers the present state of the art of quality assurance. Fundamental considerations concerning a well-defined quality concept as a basis for process control are presented in the third part, prior to explanation of the process control concept and its illustration with the aid of an example.     

Expertensysteme für die Prozeßführung,–Erfahrungen aus dem Verbundprojekt TEX-I

Expert systems for process control – experience with the TEX-I project. The paper gives a brief overview of some topics concerned with expert systems technologies in a real-time environment. After a four-year-project the perspectives of the technology are much more realistic, and the promises more or less reduced. What we see is a software-technology that is hard to use but well suited for complex applications. Unsolved is the problem of knowledge elicitation, the bottelneck of knowledge engineering.     

Statistische Prozeßführung (SPC) und Automatisierung (APC)

Statistical Process Control (SPC) and Automatic Process Control (APC). Statistial Process Control as developed by Shewhart and Deming is being used internationally as a method for continuous improvement and cost reduction. SPC is applied to manufacturing and service industries, and is now being used more and more in Germany. In the chemical industry many processes are equipped with automatic control or advanced control strategies. This article outlines how SPC and APC supplement each other. The first part describes APC methods as a means of achieving constant quality. The second part describes SPC in its original form as a method for continuous quality improvement. After the comparison of SPC and APC an example is presented: automatic rectifying column. The combined application of SPC and APC leds to synergistic results which would have been hard to achieve otherwise.