bluuebunny/crossref_metadata_2025_split huggingface dataset:
Methodik des produktionsintegrierten Umweltschutzes in der chemischen Industrie
Authors: Hassan Ali , Kostka Sebastian 
Published: December 2004

AbstractMethods for Production‐Integrated Environmental Protection in the Chemical Industry. This article describes the integration of production‐integrated environmental protection in the chemical industry into strategic planning, research and development as an optimisation problem. A holistic approach is adopted to seek a compromise between contradictory economic, ecological, and other goals; these goals have to be prioritized subjectively. The ecological demands are quantified with the aid of technical factors, efficiency, and monetary factors. A methodology for decision making in production‐integrated environmental protection is demonstrated and discussed for a number of selected applications. It is based upon exact optimization with one or multiple target quantities, efficiency analysis, and quantitative models.
Definition von Destillationslinien bei der Trennung von Mehrstoffgemischen
Authors: Vogelpohl Alfons 
Published: December 2004

AbstractDefinition of Distillation Lines in the Separation of Multicomponent Mixtures. In recent years “distillation lines” have been used for the assessment of the separation behaviour of multicomponent mixtures, with these distillation lines being defined differently by different authors. The theory of distillation of multicomponent mixtures shows that it is appropriate to distinguish between residue lines and rectification lines. While the profile of residue lines is determined solely by the thermodynamic phase equilibrium, that of rectification lines also depends upon the mass transfer model used. By analogy with VDI Guideline 2761: “Thermal Separation Processes in Process Engineering”, it is proposed that residue lines and rectification lines are designated by the collective term distillation lines.
Verhalten feinkörniger Schüttgüter
Authors: Molerus Otto 
Published: December 2004

AbstractBehaviour of Fine‐Grained Bulk Solids. The behaviour of fine‐grained bulk solids embraces such diverse phenomena as the moistening properties or thermal conductivity. Only two aspects are considered in this article, viz, the mechanics of bulk materials and the flow mechanics of fine‐grained bulk solids. The interplay of these two areas is illustrated by a detailed analysis of the various kinds of gas fluidisation.
Nichtporöse Membranen und ihre Anwendung
Authors: Cen Yanwei , Meckl Karin , Lichtenthaler Rüdiger N. 
Published: December 2004

AbstractNon‐porous Membranes and their Applications. In recent years membrane systems have gained increasing industrial importance in the separation of multicomponent mixtures. This also applies to porous membranes in which the mass transfer is effected by the difference in electrochemical potential of the permeating components on the feed and permeate sides. After presenting the construction and the mode of operation of non‐porous membranes, the article considers industrial membrane processes. Special attention is focussed on development work starting from the research results obtained in the laboratory and culminating in the industrial application. The development of membranes with support‐bound „passive”︁ or „active”︁ transport, such as encountered in some biological membranes, offers interesting insights.
Formbarkeit keramischer Massen durch Extrusion
Authors: Gleißle Wolfgang , Graczyk Jan 
Published: December 2004

AbstractExtrusion and Formability of Ceramic Pastes. Numerous complicated catalyst geometries are produced by extrusion of plastic ceramic materials. The demands on the precision of the forming process and the formability of the materials are extremely high. At a first glance, plastic ceramic materials seem to be concentrated solid‐liquid suspensions. Rheometric methods, in particular capillary rheometry, are especially suitable for testing of these materials. However, the flow processes occurring during extrusion are very complex, with many special effects such as slip, shear‐thinning, shear hardening, high entrance pressure loss. Viscosity functions are not material functions. However, in spite of these difficulties, capillary rheometry, when critically applied, is a most advantageous tool in the purposeful development of easily extrudable ceramic materials. Correlation of the rheometric test results with the extrusion process during the production of honeycomb geometries is presented using aluminium oxide ceramics as an example.
Umweltschutz und Sicherheit: Die Verantwortung des Ingenieurs
Authors: Lipphardt Günter 
Published: December 2004

AbstractResponsibility of the Engineer for Environmental Protection and Safety. Engineers in industry are expected to focus uncompromisingly on environmental protection in their work. A demand of this kind would require the absolute truth concerning the yardstick against which the features are to be measured. However, there is no such yardstick. In addition, most alternatives are not entirely free of environmental impact. Which ones can or must the engineer's choose? Apart from technical and scientific limits, there are also economic limits within which engineers must act in order to realize new technologies. On the other hand, engineers must speak up for those areas which they consider on the basis of their knowledge and experience, to be essential to the interests of the general public and the economy. This applies not only to activities in the field of engineering, but also to personal involvement in the public sphere. This is an area that still offers considerable scope.
Neue Technologien — neue Korrosionsprobleme
Authors: Heitz Ewald 
Published: December 2004

AbstractNew Technologies – New Corrosion Problems. Adequate resistance of materials to corrosion is equally important for classical and for new technologies. This article considers the economic consequences of corrosion damage and, in addition to the longknown GNP orientation, presents a new approach to the estimation of the costs of corrosion and corrosion protection via maintenance and especially corrosionrelated maintenance. The significance of “high‐tech”, “medium‐tech” and “low‐tech” material and corrosion problems is assessed. Selected examples taken from new technologies in the areas of power engineering, environmental engineering, chemical engineering, and biotechnology demonstrate the great significance of the problems. It is concluded that corrosion research and corrosion prevention technology will never come to an end but will constantly face new problems. Two technologies are of particular interest since they focus attention on new methods of investigation: microelectronics and final disposal of radioactive wastes. The article closes by considering the importance of the transfer of experience and technology. Since the manufacturs and operators of machines and plant do not generally have access to the very latest knowledge, they should be kept informed through advisory services, experimental studies, databases, and further education.
Simulation des instationären hydraulischen Verhaltens verfahrenstechnischer Anlagen mit langen Rohrleitungen
Authors: Raschke Erhard , Seelinger Peter , Sperber Axel , Straßburger Rolf 
Published: December 2004

AbstractSimulation of Transient Hydraulic Behaviour Process Engineering Plant with Long Pipes. A knowledge of transient flow processes is becoming increasingly important for the reliable design and control of process engineering plant. Transient flow processes occur, of example, in long liquid‐carrying pipes: on start‐up and shut‐down of plant, in emergency shut‐downs and fast closure, i.e. when liquid is rapidly decelerated or accelerated. The consequence of such an event is a hammer effect, i.e. a short, often violent change of pressure placing considerable stress on structures. Such hammer effects are readily calculated by numerical methods in single phase media. Technical devices for prevention of inadmissibly high pressures surges can also be designed by means of simulation calculations. However, hammer effects also occur by sudden condensation of vapours. A number of systems in which condensation hammer effects can occur are considered at the end of this contribution. Two special damping measures are presented.
Entwicklungsstand der Alkalichlorid‐Elektrolyse. Teil 1: Zellen, Membranen, Elektrolyte, Produkte
Authors: Bergner Dieter 
Published: December 2004

AbstractState of the Art in Alkali Chloride Electrolysis (I). Cells, Membranes, Electrodes, Electrolytes, Products. The state of the art in the field of alkali chloride electrolysis for the production of chlorine, alkali hydroxide and hydrogen is characterized by the state of development of the membrane cell process. By 1996 about 230 membrane electrolysis plants with a combined NaOH capacity of about 11 million metric tons will be on line worldwide. This amounts to roughly one fourth of the world's caustic soda production by electrolysis. In this review the main membrane cell technologies, the ion exchange membranes of different suppliers and anodes and cathodes of the membrane cells are described. This first part of the review ends with a look at the problems of brine quality for the membrane cells and a description of the products chlorine, caustic soda solution and hydrogen.
Planung der Kuppelproduktion in Systemen von chemischen Mehrzweckanlagen
Authors: Jänicke Winfried 
Published: December 2004

AbstractPlanning of Coupled Production in Multipurpose Chemical Plant. This article considers strategies for computer‐aided planning of coupled production for systems of net worked multipurpose plant. Reasons are given for the failure of classical strategies such as are used in PPS systems. A procedure is described which, starting from a final product, automatically generates a cascade of previous product jobs and assigns them to production lines along a time axis (simultaneous material, pecursor, and production line assignment planning). Possibilities of interactive improvements of a given solution on consideration of factors such as storage costs and turnover are presented.
Chemieanlagenbau — Märkte im Osten
Authors: Jaeschke Lothar 
Published: December 2004

AbstractMarket for Chemical Plant in Eastern Europe. For reaching changes in the former Comecon countries have led to totally altered market structures, and these developments are continuing. The most serious problems arise from the precarious financial situation, altered and unclear decision processes, also with regard to the difficult disbanding of the state sector, and above all the totally inadequate economic legislation. Since the former Comecon countries will undoubtedly be one of tomorrow's main markets, western plant constructors must already give this market very serious attention, although it will take some considerable time until complete economic stability is reached. Collaboration with local partners is often a good way of consolidating a market presence, with a range of possibilities including cooperation, joint ventures, or purchase of a local company. Setting up one's own company is an alternative approach. Which ever route is selected, it is of greatest importance that the customer is extensively involved in all stages of completion of the order.
Abluftreinigung und Lösungsmittel‐ Rückgewinnung durch Adsorption an Adsorberharzen
Authors: Reschke Güunter , Mathews Waldemar 
Published: December 2004

AbstractCleaning of Exhaust Air and Solvent Recovery by Adsorption on Polymer Resins. In an overview the technologies of air cleaning and solvent recovery is followed by an account of the adsorption of solvents on polymer resins. Test plant, experimental adsorption equilibria and breakthrough curves as well as mathematical modelling for the design of fixed bed adsorbers are the main focus of attention. Practical examples demonstrate the advantages of using polymer resins in solvent recovery.
Chemiestandort Europa – Herausforderungen und Strategien
Authors: Bufe Uwe‐Ernst , Altwegg Markus , Schultze Wolfgang , Schadow Ernst 
Published: December 2004

AbstractEurope as Location for the Chemical Industry – Challenges and Strategies. During Achema '94 visitors were invited to attend a number of panel discussions. One of these addressed the subject of Europe as a location for the chemical industry. The highly topical nature of this subject matter and the consequences for each one of us if the attractiveness of Europe for the chemical industry continues to wane were reasons enough for Chemie Ingenieur Technik to publish the main content of this discussion. Participants in the discussion were Dr. Uwe‐Ernst Bufe, Degussa AG, Frankfurt, Dr. Markus Altwegg, Hoffmann‐La Roche, Basel, Dr. Wolfgang Schultze, of the Labour Organisation IG Chemie Papier Keramik, Hannover, Dr. Ernst Schadow, Hoechst AG, Frankfurt. The discussion was mediated and chaired by Hans‐Wolfgang Pfeifer of the Frankfurter Allgemeine Zeitung Group.
Modellierung des Stoffaustausches von flüchtigen organischen Verbindungen in hochviskosen Medien
Authors: Warnecke H.‐J. , Prüss J. , Hübinger W. , Minges R. 
Published: December 2004

AbstractModelling of Mass Exchange of Volatile Organic Compounds in High‐Viscosity Media. Polymers may contain low‐molecular weight organic components as a result of incomplete reaction during polymerisation, contamination of the reactants, and undesired side reactions. Aqueous of polymers are usually applied to surfaces (emulsion paints, adhesives, paper finishing agents, etc.). Since low molecular components then escape into the air, they are removed after polymerisation by stripping the product with an inert gas. While the engineering used for this step is well developed, the mass transfer processes involved have received little yet controversial attention. This paper presents a mechanistic mathematical model which includes the mass transfer steps occurring during stripping in a stationary continuously operating apparatus with complete back‐mixing. Measurements of the position of phase equilibria and determination of the depletion achievable in an aerosol jet loop reactor demonstrate that, provided that the temperature of treatment exceeds the glass transition temperature, the stripping process is determined solely by the partition coefficients of the exchanged components between the phases, the hydrodynamic parameters, and the reactor operating conditions. This contradicts the claims of some authors that diffusion processes in the latex particles are of decisive importance.
Abscheidung aus überkritischen Gasen
Authors: Birtigh Andreas , Brunner Gerd 
Published: December 2004

AbstractPrecipitation from Supercritical Gases. The importance of processing substances with supercritical gases as a separation method has increased in recent years, particularly as a means of obtaining products produced without organic solvents. This article surveys the various methods of depositing substances from a supercritical phase. The surest method, i.e. that of reducing the pressure to subcritical values, involves a high energy consumption for recompression of the phase when performed on an industrial scale. For this reason, isobaric deposition methods (adsorption, absorption, membrane separation) were examined to establish their suitability for regenerating the supercritical solvent.
Einsatz eines Aerosolmassenspektrometers (AMS) zur Untersuchung von Partikelbildungsprozessen in Hochtemperaturreaktoren
Authors: Hospital Andreas , Roth Paul 
Published: December 2004

AbstractAerosole sind Zweiphasengemische bestehend aus einer Gasphase, in der in feinster Verteilung feste und/oder flüssige Partikel schweben. Sie können in unterschiedlichen Bereichen der Verfahrenstechnik entweder als unerwünschtes Abgas auftreten oder als Produkt gezielt generiert werden.
Bestimmung kinetischer Konstanten der radikalischen Polymerisation mittels adiabatischer Reaktionskalorimetrie unter Berücksichtigung der Molmassenverteilung
Authors: Mosebach Michael , Reichert Karl‐Heinz 
Published: December 2004

AbstractDas beschriebene Verfahren bestimmt kinetische Daten radikalischer Polymerisationen in Lösung mittels der adiabatischen Reaktionskalorimetrie unter Berücksichtigung der resultierenden Molmassenverteilung des Endprodukts. Als Beispielreaktion dient dabei die radikalische Polymerisation von Methylmethacrylat (MMA) in Toluol mit 2,2′‐Azobis (2,4‐dimethyl‐valeronitril) (ADVN) als Initiator. Es konnte bereits gezeigt werden, daß sich aus den im adiabatischen Reaktionskalorimeter gemessenen Temperatur/Zeit‐Verläufen Bruttogeschwindigkeitskonstanten der Polymerisation von MMA ohne Geleffekt [1, 2] und mit Geleffekt [3, 4] bestimmen lassen. Bei Kenntnis eines geeigneten mathematischen Modells zur Beschreibung des Reaktionsablaufs können anhand des gemessenen Temperatur/Zeit‐Verlaufs der Polymerisation und der Molmassenverteilung des Polymers auch Werte für die Elementarreaktionen bestimmt werden.
Modellierung reaktiver Stoffaustauschprozesse
Authors: Brinkmann Manfred , Warnecke Hans‐Joachim , Prüss Jan 
Published: December 2004

AbstractThe design of reactive exchange processes is generally accomplished with the aid of the enhancement factor, whose calculation is frequently possible only by iterative and approximate methods. In contrast, a mathematical model linking microscopic reaction‐diffusion equations with macroscopic phase balances permits direct calculation of absorption. Complication reaction pathways and non‐linear phase equilibria can then also be considered without making simplifying assumptions. The influence of liquid phase viscosity on exchange parameters can be quantified and included in model calculations by coupling the more comprehensive film penetration theory and the theory of isotropic turbulence. Simulations not only demonstrate the influence of the system and operating parameters on absorption but also indicate the importance of the choice of excange model in systems with conversiondependent liquid phase viscosity.
Analyse und Anwendung dynamischer Optimierungsalgorithmen für Batch‐Prozesse
Authors: Li Pu , Wozny Günter 
Published: December 2004

AbstractBatch processes being increasingly used in the chemical industry. The advantages of batch processes are their flexibility, high product purity and the possibility of frequent product changeover. For the economical operation of a batch process it is necessary to develop an optimal strategy; therefore a proper optimisation approach is required. For this reason two different optimisation algorithms, differential dynamic programming and a simultaneous optimisation approach, are investigated in this paper. The characteristics of the algorithms are worked out and their efficiency is analysed. Simulation results from batch reactors and a batch column demonstrate the scope of application of the algorithms.
Intervallmathematische Methoden in der Prozeßtechnik — Flexibilität und Unschärfe
Authors: Gruhn Günter , Colditz Stefan 
Published: December 2004

AbstractDas Anliegen dieses Beitrags besteht darin, neuartige Vorgehensweisen der mathematischen Modellierung, Simulation und Optimierung verfahrenstechnischer Prozesse im Hinblick auf die Behandlung von Entwurfs‐ und Steuerungsproblemen vorzustellen. Diese Vorgehensweisen beruhen auf der Anwendung von Grundgedanken und Methoden der Intervallmathematik und deren Anpassung an Problemstellungen der Verfahrenstechnik.
Funktionale Kolloide: Strukturbildung und Chemie im Nanometerbereich
Authors: Antonietti Markus 
Published: December 2004

AbstractColloid chemistry is the science of the finely divided state of material. Colloids are small units of gas, a liquid, or a solid whose size is measured in nanometers. Systems containing or made up of colloids can have special properties differing significantly from those of the molecules from which the colloid particles are made and from those of the corresponding bulk material. The colloidal state is therefore sometimes described as the “fourth state of aggregation”. Fundamental properties such as melting point, conductivity, or the optical parameters depend upon particle size. Modem colloid chemistry thus provides considerable scope for the production of new materials with new combinations of properties through control of the chemical composition on a nanometer scale. These possibilities are considered in the light of a number of research projects being pursued at the Max Planck Institute for Collid and Interface Research.
Struktursynthese und Optimierung nichtidealer Rektifizierprozesse
Authors: Bauer Markus H. , Stichlmair Johann 
Published: December 2004

AbstractOptimization processes with MINLP are inherently capable of dramatically reducing the effort and time required for synthesis and analysis of separation processes. This approach represents an extremely powerful tool whose use, however, requires an understanding of process engineering. The principal advantage of the method lies in the simultaneous optimization of both the structure and also the operating conditions of a process. Reliable convergence to the global optimum requires careful limitation, scaling, and prior assignment of all variables. Starting values can be obtained by thermodynamic analysis of the phase equilibrium and by an overall balancing of the individual separation steps. Heuristic reduction of the superstructure generated on the basis of the preferred separation, appears appropriate given the present status of available models and solution algorithms. Under these conditions, the outer approximation algorithm recommended for this model will find the optimum solution after just a few iteration steps.
Das Beschichten von Oberflächen
Authors: Klostermann Rainer , Mewes Dieter 
Published: December 2004

AbstractThe coating of different substrates is an important part of many industrial manufacturing processes. The fluids used in these processes have very different rheological properties. They are coated to solid surfaces with high substrate velocities by dipping, spraying, casting or by the use of knives, blades and rollers. The field of flow between two rotating rollers is influenced by the free surface of the fluid and the contact point between the three phases, solid roller, coating fluid, and the surrounding gas. Viscous, inertial, gravitational and capillary forces control the velocity field between the rollers. Stable fluid coatings that satisfy the increasingly stringent demands on the quality of their surface structure have to be created within certain limits of the forces occurring. In order to predict these limits, the flow fields have to be completely calculated. Therefore all three conservation equations and an additional equation for the position of the free surfaces are solved with consideration of the constitutive equations and possible wall slip effects of the coating fluids.
Basismodelle für Reaktoren — eine kritische Bilanz
Authors: Platzer Bernd 
Published: December 2004

AbstractIn the literature of chemical reaction engineering, the basic models for reactors are deduced in different ways. This paper demonstrates that the authors do not always stringently differentiate between fluid mechanics and chemical reaction engineering methods. Thus misinterpretations may arise. As this publication shows, it would be more precise to use instead of ideal reactors the term completely/radially mixed reactors (mixing vessel/pipe). In addition, attention is directed to convection reaction models. They give an idea of the local concentration profiles in reactors for a small mathematical effort. The models give predictions superior to those of the ideal reactor models and of the dispersion model, both of which can only give mean values.
Innovation gleich Information plus Intuition
Authors: Blass Eckhart 
Published: December 2004

AbstractAs a consequence of the structural crisis of German industry, politicians and business leaders are increasingly calling for new and improved products, new and better processes. Innovation is in great demand. Yet what is innovation? How do innovations happen and how can they be promoted? What kind of scientific and technical environment is needed to produce a rich crop of innovations? Good information sources can be an enormous help.