bluuebunny/crossref_metadata_2025_split huggingface dataset:
Elektrische Energie und Umwelt
Authors: Krieb Karl Heinz , Dorstewitz Ulrich 
Published: December 2004

AbstractElectrical energy and environmental protection. Power plant affect their environments by emitting noise, heat, and air pollutants, but can be operated, according to the present state of the art, in such a way as to lessen these effects. The noise levels will then be below those of a quiet restaurant; the heat emission above the cooling tower will influence neither climate nor the volume of rainfall, and will influence the amount of incident solar radiation to only a minor degree; the dust emission in g/k Wh has decreased by 97% during the last 30 years; the SO2 emission will have decreased by 80% by 1980; the dilution of the SO2 emission through use of high stacks will lead to maximum SO2 levels of 2 μg/m3 in case of modern power plants; all these are low values compared with the upper limits of 140 μg/m3 permitted by the “Technische Anleitung Luft”. It is worth mentioning in connection with the problems with present environmental protection that the per capita electricity consumption of private households has increased much faster than that of industry.
Alkalische Batterien für Elektrostraßenfahrzeuge – technische und wirtschaftliche Aspekte
Authors: Plust Heinz G. 
Published: December 2004

AbstractAlkali batteries for electric vehicles – technical and economic aspects. The running of an electric vehicle places certain demands on the battery used as source of energy. An important factor is the relationship between storage capacity and good loadability. Of the battery systems currently under development it is found that alkali accumulators satisfactorily fulfil most of the important requisites. As a survey of these systems shows, alkali accumulators have now reached such a state of development that their employment in vehicles can be realistically discussed from the technical point of view. The systems Ni/Zn and Ni/Fe are the most promising, and economic considerations would suggest that alkali accumulators can be employed instead of lead/acid accumulators, even if the battery costs are relatively higher.
Technische und wirtschaftliche Überlegungen zur Elektrotraktion – VW‐Elektro‐Transporter
Authors: Kalberlah Adolf , Schimkat Harald 
Published: December 2004

AbstractTechnical and economic aspects of electrically powered VW commercial vehicles. The article first describes the “VW Electric Delivery Truck System”, consisting of the vehicle and the peripheral equipment to operate it, and then reports experience gained with this type of vehicle, of which more than 70 have been registered for operation on public roads since 1972. On the basis of these VW commercial vehicles, which are equipped with lead‐acid batteries, the authors discuss the potential advantages of using new types of batteries with twice the energy to weight ratio. The resulting vehicle versions and their total weights, payloads, battery weights, energy requirements, and operating costs are reviewed. It is shown that a considerably higher price for batteries with twice the energy/weight ratio would be acceptable under certain circumstances.
Creeping fronts and travelling waves
Authors: Aris Rutherford 
Published: December 2004

AbstractSome of the ramifications of Wicke's work on creeping fronts in fixed beds are reviewed in this paper. His work laid the experimental foundations for model building by Vortmeyer and Jahnel on the one hand and by Amundson and Rhee on the other. These workers showed how slowly moving waves could arise in various models of these systems. The relation between such a creeping front and a travelling wave of fixed form is further discussed and some of the more recent biological applications are mentioned.
Konstruktive Lösungen zur Maßstabsvergrößerung von mehrphasig durchströmten Apparaten
Authors: Mewes Dieter , Dahm Franz Ludwig , Kurandt Uwe 
Published: December 2004

AbstractDesign approaches for the scaling‐up of multiphase flow apparatus. The scaling‐up of apparatus from the laboratory‐to the industrial‐scale is illustrated with aid of two examples. Phase partition during the flow of liquids and gases through packing layers is dealt with. It requires particular attention if the volumes of flow are different and if the efficiency of material exchange on an industrial scale referred to volume is to be the same as on a laboratory scale. A design approach for the uniform distribution of a small volume of gas in uniflow with a large volume of liquid is described. For counter‐current flow of large volumes of gas and small volumes of liquid an arrangement of packing with least possible drop in pressure is required. Some well‐known packings are compared, taking into account measured results for a novel packing referred to as “impulse packing”.
Strömungsturbulenz und Verbrennung
Authors: Günther Rudolf 
Published: December 2004

AbstractTurbulent flow and combustion. Flame‐generated turbulence was long a topic of lively discussion. Since the hot gases arising on combustion are much more viscous than, e.g. cold air and cold natural gas, the Reynolds number of a flow system is more likely to fall. Indeed, combustion is observed to promote laminar flow at low Reynolds numbers. The concept of “flame‐generated” turbulence was imprecisely defined; a predominant thought was concerned with the turbulence‐reinforcing effect of combustion in an existing field of turbulent flow. Some authors doubted whether such an effect is possible. Meanwhile, it has been established that combustion can affect turbulent exchange in various ways, as demonstrated in this paper.
Hochdruck‐Polyäthylen
Authors: Luft Gerhard 
Published: December 2004

AbstractLow‐density polyethylene. The constantly changing economic situation requires periodic re‐assessment of the general direction of process and product development. This contribution surveys the present state of the art of high‐pressure polyethylene synthesis with due consideration of recent developments. Starting from chemical and chemical‐engineering fundamentals, the various polymerization processes and their products are compared and contrasted, and an attempt is made to predict further developments.
Verfahrenstechnik für den Umweltschutz
Authors: Biedenkopf Gerhard 
Published: December 2004

AbstractIndustrial process engineering and environmental protection. Industrial process engineering involves not only the realization of chemical‐physical processes but also the optimization of the economics of a plant and the minimization of environment pollution. Since the incorporation of additional facilities in a process for the reduction of emission has been brought to a high technical standard in recent years, more and more attention will now be directed to achieving a high selectivity in favor of the product in the chemical reaction by suitable process control. It is shown with the aid of schematically represented mass balances and cost diagrams that emission can be reduced by process engineering optimization of a process, leading to a decrease in both the costs incurred from environmental pollution and the costs for the preventative measures taken.
Berstsicherheit von Chemie‐Apparaten
Authors: Gaube E. , Braubach H.‐O. , Dickhäser M. 
Published: December 2004

AbstractBurstproofness of chemical apparatus. The first part of the paper deals with the safety requirements that have to be met by pressure vessels, the interaction of material behaviour and structural form, and the design principles in industrial codes. An important pre‐requisite for the avoidance of brittle fractures is material toughness also at those parts of the pressure vessels where increases in stress due to the shape of the vessels cannot be avoided. As a result of the development of new materials, the Dechema technical committee „Materials and design in the construction of chemical apparatus”︁ constituted the working party “Strength and toughness” in 1962 and assigned to it the task of carrying out bursting tests on model pressure vessels similar in size and shape to those used in practice, the purpose being to tudy the influence of material toughness and vessel shape on burstproofness. This study, which was completed early in 1979, is reported in the second part of this article.
Neuere Erkenntnisse und Anwendungen bei der elektrischen Abscheidung von Stäuben und Nebeltröpfchen
Authors: Mayer‐Schwinning Gernot , Rennhack Rolf 
Published: December 2004

AbstractNew insights and applications in the electrostatic precipitation of dusts and mists. The introduction deals with the basic design, the mode of operation, and the fields of application of dry and wet type electrostatic precipitators. A few important parameters which influence the migration velocity are discussed. Contrary to what the classical theory states, greater passage widths lead to higher migration velocities of the particles and thus to a higher specific efficiency. The methods for conditioning flue gases of power stations are considered, as are the experimental results obtained in an industrial‐scale SO3 conditioning plant. A new field of application is seen in the steel industry through the use of a dry type electrostatic precipitator of special design. New plastic precipitator developments for the chemical industry are discussed, and the articles closes with an account of the efforts invested in developing hot gas precipitators for higher temperatures and pressures in connection with the introduction of new power station concepts.
Erste fernbediente, vollautomatisierte Verdichterstation für Ethylen in Deutschland
Authors: Borner Joachim , Braun Rainer , Nieding Walter 
Published: December 2004

AbstractFirst remote‐controlled, fully automated ethylene compressor plant in Germany. The Hoechst company has been operating an ethylene pipeline between Cologne and Frankfurt‐am‐Main since 1960. The capacity of this pipeline had to be increased from 250 000 t/a to 350 000 t/a, and this is why a remote‐controlled fully automated ethylene intermediate compressor came into operation in 1978. The unmanned station was constructed as a grass roots project with ancillary and safety displays and is controlled and monitored from an 80‐km distant control desk. Compression is by two piston compressors arranged in parallel, with each one accounting for 50% of the throughput capacity. Particular attention was paid to the safety concept of the station. All interlocking systems necessary and possible manual operations are permanently wired. The start‐up and shut‐down programs are located in a freely programmable control system. Such stations can be constructed from prefabricated units in inaccessible areas.
Wärmeübergang in Rührkesseln mit mehrphasigen Systemen
Authors: Steiff Artur , Poggemann Reinhold , Weinspach Paul‐Michael 
Published: December 2004

AbstractHeat transfer in agitated vessels with multiphase systems. Heat transfer behaviour in agitated vessels with gas liquid, liquid liquid, solid liquid, and solid gas systems is analysed and presented on a similarity theory basis. Experimental results and proposed methods of calculation given in the literature are compared critically; the subject of scaling‐up is also dealt with. The present paper is restricted to simple multiphase systems with Newtonian and non‐Newtonian flow behaviour. In the case of complex multiphase systems, as are often met with in practice, i e. systems with kneadable or pasty consistency with significant separation, creaming, or settling phenomena, or with a tendency to incrustate, further investigations are necessary, taking into consideration the results already given in the literature. Working equations presently available for the calculation of indirect heat transfer in agitated vessels with gas/liquid, liquid/liquid, solid/liquid, and gas/solid systems have been collected in tables; these can be ordered from the „Lehrstuhl für Thermische Verfahrenstechnik”︁, Universität Dortmund, Postfach 500 500, D‐4600 Dortmund 50.
Kristallisation aus Schmelzen
Authors: Matz Günther 
Published: December 2004

AbstractCrystallization from melts. Equipment for crystallization from melts differs considerably from the solution crystallizer. The article discusses: Trough crystallizers, belt crystallizers, pastillators, flakers, screw crystallizers, and prilling towers. The kinetics of melt crystallization is simpler than that from solution, and the secondary nucleation becomes less important. Environmentally, crystallization from melts is more attractive because absence of solvent obviates waste products. Dust problems are avoidable by flaking, pastillizing, and prilling.
Eigenschaften hochtemperaturhydrolytisch hergestellter Kieselsäuren und Metalloxide für Katalysatoren
Authors: Koth Detlev , Ferch Horst 
Published: December 2004

AbstractCatalytic properties of silicic acids and metal oxides prepared hydrolytically at high temperatures. The physical and chemical properties of silicic acids and metal oxides (Al2O3 and TiO2 P25) prepared hydrolytically at high temperatures are described, insofar as they might be of interest to catalyst producers. A highly topical literature survey reveals areas of interest in the fields of research and practical applications. The experimental section deals with the preparation of catalyst supports made of highly dispersed silica gel products. Their characteristics are tabulated.
Anfahr‐ und Betriebsverhalten von exothermen Batch‐Prozessen
Authors: Hugo Peter 
Published: December 2004

AbstractStart‐up and operation of exothermic batch processes. A survey of the general characteristics of batchwise chemical production processes shows that the possibilities of complete prediction of optimum production tactics are limited. Thus recourse is taken to simplified semi‐empirical design procedures. It is demonstrated in the case of exothermic batch processes with indirect cooling that criteria can be given as to whether this production strategy is technically feasible. Given technical feasibility, these criteria can be used for design of a safe start‐up and operating behaviour. The procedure is illustrated for two applications.
Der Sicherheitsaspekt beim Eintrag von Schüttgütern in Behälter
Authors: Simon Eberhard 
Published: December 2004

AbstractSafety aspects of charging bulk material into vessels or containers. The safe charging of bulk material requires a careful analysis of the potential sources of danger which can result from the physical properties of the materials and the design and construction material of plant and equipment. The method adopted in this analysis is illustrated and explained for selected examples. Criteria for safe charging methods are compiled and explained. A selection of proven charging equipment is listed and technically evaluated with respect to safety and operating criteria. Steps that must be taken to avoid charging errors are discussed. Special problems encountered on connecting pressureless charging devices to pressure vessels are outlined explained. The utilization of inert gas as a preferred method of explosion protection is discussed. Various methods are compared, and their application to special problems in charging bulk material is illustrated.
Verbesserte Kostenschätzungen durch Anwendung von Mengen‐ und Mannstunden‐Verhältniszahlen
Authors: Groen B. , Tan K. D. 
Published: December 2004

AbstractImproved cost factor estimation with quantity and man‐hour ratios. Present‐day cost estimation on a multi‐currency basis is becoming more and more complex due to the wild and frequent fluctuations of exchange rates and different inflationary trends in various countries. The preparation of comparatively accurate preliminary cost estimates, based on world‐wide procurement, overseas construction and engineering, became a major problem for companies like badger with international activities. To maintain an acceptable degree of accuracy, the traditional method of cost factor estimation has to be supplemented with a quantity and man‐hour ratio method. Basically, costs are related to quantities; therefore cost ratios can be converted into quantity ratios. Man‐hour ratios originate from the existing relationship between quantities, material costs, and field man‐hours to install these quantities. In this article the value of the Quantity Ratio Method as a tool in these unstable times will be stressed, as well as the added advantages it offers with regard to better cost control and communication.
Zum Flutpunkt in Flüssig/Flüssig‐Gegenstromkolonnen
Authors: Mersmann Alfons 
Published: December 2004

AbstractFlooding point of liquid‐liquid countercurrent columns. Calculation of the column diameter for given volumetric flow rates of the raffinate and the extract phases requires a knowledge of the flooding point. A simple flooding point diagram is presented which contains the rise or fall rate of an individual drop as intermediate quantity. The principal experimental results from the literature obtained in countercurrent columns with and without introduction of energy by rotation and pulsation are compared with the flooding point diagram.
Standortgefertigte Druckbehälter
Authors: Straub Hermann 
Published: December 2004

AbstractDas Arbeitsgebiet der standortgefertigten Druckbehälter ist so umfangreich, daß eine vollständige Übersicht weit über den Rahmen eines einzigen Beitrages hinausgeht. Es werden daher vorwiegend Kugeldruckbehälter für verdichtete oder verflüssigte Gase behandelt. Andere große Druckbehälter wie Reaktoren und Sicherheitshüllen werden nur am Rande erwähnt. Dabei interessieren in erster Linie der Stand der Technik sowie die damit verbundenen Probleme und Entwicklungstendenzen und dies nicht zuletzt im Hinblick auf das ständig wachsende Sicherheitsbedürfnis der Bevölkerung gegenüber der Technik.
Flüssigphase‐Rückvermischung in gepackten Blasensäulen
Authors: Gestrich Wolfgang , Harth Hubert 
Published: December 2004

AbstractFür die Flüssigphase‐Rückvermischung in mit Metallraschigringen und ‐pallringen gepackten Blasensäulen werden Korrelationen für den axialen Dispersionskoeffizienten in der Form Peg = f (Ga, Reg, H/D) angegeben. Die Einzelabhängigkeiten von Stoff‐ und Betriebsgrößen werden anhand von Diagrammen ausführlich erläutert. Pallringe vermögen in Säulen mit Durchmessern D > 20 cm Großwirbel und Rückvermischung nur unvollkommen zu unterdrücken. Auch für diesen Bereich wird eine Faustformel für den scheinbaren Dispersionskoeffizienten angegeben. Dagegen sind Raschigringe zur Unterdrückung der Rückvermischung gut geeignet. Es wird auf die Problematik von Modellerfüllung und störungsfreier Messung der Rückvermischung eingegangen.
Perspektiven für die Forschung im Chemieingenieurwesen: Die französische Politik
Authors: Villermaux Jacques 
Published: December 2004

AbstractDie französische Regierung hat vor einigen Jahren einen Ausschuß gegründet, um zu bestimmen, welche Forschung in der Zukunft auf dem Gebiet des Chemieingenieurwesens in Frankreich betrieben werden soll. Das Ergebnis dieser Überlegungen wird hier vorgestellt. Zuerst wird der jetzige Stand der französischen Forschungsinstitute kurz beschrieben: Programme, Struktur, Finanzierung und Zusammenarbeit mit der Industrie. Im zweiten Teil werden die Probleme beschrieben, die sich in einer technisch orientierten Gesellschaft stellen, bei deren Lösung das Chemieingenieurwesen seinen Beitrag leistet. Die bei der Übertragung chemischer Verfahren vom Labor‐ zum technischen Maßstab erzielten Erfolge werden hervorgehoben, die folgenden Schwerpunkte werden genannt: systemtheoretische Vorgehensweise, Modellierung zur schnellen und sicheren Auslegung, schnelle Anpassung der Verfahren bei sich ändernden wirtschaftlichen Randbedingungen, Ausdehnung der im Chemieingenieurwesen üblichen Begriffe auf andere Gebiete (Biologie, Lebensmittel‐ und Bodentechnik, elektrochemische, Sonnen‐ und Kernverfahrenstechnik usw.). Noch ungelöste Probleme und zukunftsträchtige Forschungsthemen werden vorgestellt: Wärme‐ und Stoffaustausch in Mehrphasensystemen, exergetische Prozeßanalyse und Ursachen des Exergieverlusts in Einheitsverfahren, neue Trennverfahren und Reaktortypen, Verfahren mit regenerierbaren Rohstoffen, Automatisierung der Prozeßfüfhrung.
Energieeinsparung in der Verfahrenstechnik
Authors: Arnold D. , Bartmann L. 
Published: December 2004

AbstractEnergiekosten sind für Wärmeprozesse in der chemischen Industrie bekanntlich ein wesentlicher Kostenfaktor. Seit der beträchtlichen Preissteigerung der Primärenergieträger sind weltweit Bemühungen im Gange, die spezifischen Energiever‐brauchszahlen bei der Herstellung chemischer Produkte zu senken. Im ersten Teil der Arbeit werden theoretische Überlegungen über Möglichkeiten der Energieeinsparung in der chemischen Industrie angestellt. Stark im Vordergrund steht das Bestreben, bei der Durchführung von Prozessen möglichst wenig Primärenergie einzusetzen. Besondere Schwerpunkte sind thermodynamische Betrachtungen von Wärmepumpen, mehrstufigen Prozessen sowie der möglichen Integration von Gegendruckkraftwerken in einem Chemiekomplex. Im zweiten Teil der Arbeit werden anhand geplanter und praktisch ausgeführter Beispiele konkrete Hinweise auf Energieeinsparungen gegeben. Hierbei wird berücksichtigt, daß während der letzten Jahre die relative Preissteigerung von Primärenergien größer ist als die von Investitionsgütern.
Vorausberechnung von Flüssig/Flüssig‐Gleichgewichten
Authors: Arlt Wolfgang , Grenzheuser Peter , Sørensen Jens Mourits 
Published: December 2004

AbstractDie Kenntnis des Phasengleichgewichts der beteiligten Stoffe ist für die Auslegung von Extraktionsanlagen von wesentlicher Bedeutung. Während man sich früher auf empirische und halbempirische Verfahren stützen mußte, gelingt heute die Berechnung von Flüssig/Flüssig‐Gleichgewichten mit Modellen aus der molekularen Thermodynamik. In diesem Übersichtsartikel werden Datenquellen, Berechnungsgrundlagen und Methoden zur Berechnung polynärer Flüssig/Flüssig‐Gleichgewichte behandelt sowie Resultate und Genauigkeit der modernen Methoden verglichen.
Grundlagen einer sicheren Chemieproduktion
Authors: Lippert Axel , Pilz Volker 
Published: December 2004

AbstractSchrittweises Vorgehen und ständig wiederkehrende Überprüfungen sowie systematische Störungsanalysen sind wesentliche Elemente bei Entwicklung, Planung und Betrieb sicherer Chemieanlagen. Das läßt sich anhand der grundsätzlichen Vorgehensweisen überzeugend darlegen. Die Diskussion einiger Methoden der systematischen Sicherheitsanalyse und ihre Anwendung auf ein einfaches Beispiel machen andererseits die Grenzen sicherheitstechnischer Maßnahmen deutlich. Die Sicherheit im Chemiebereich ist im Planungsstadium nicht zu quantifizieren. Wohl aber läßt sich durch Hinweis auf alle bisherigen Erfahrungen zeigen, daß nach dem Stand der Technik errichtete Chemieanlagen ausreichend sicher sind.
Gedanken zur Qualitätssicherung beim Bau von Chemieanlagen
Authors: Gräfen Hubert , Gerischer Karl 
Published: December 2004

AbstractUm eine Chemieanlage gefahr‐ und störungsfrei betreiben zu können, ist eine Vielzahl von Maßnahmen zur Qualitätssi‐cherung bei der Planung, während des Baus und im Betrieb notwendig. Anhand eines Beispiels, nämlich eines großen Reaktors, werden diese Maßnahmen geschildert. Dabei wird besonders auf die einzelnen Bauphasen und die zwischenge‐schalteten zerstörungsfreien Prüfungen eingegangen, berührt werden aber auch die Qualitätsplanung, die Qualitätssiche‐rung im Betrieb und die Organisation des Qualitätswesens. Das Beispiel soll zeigen, daß noch so viele Qualitätsdokumentationen die Bereitschaft der beteiligten Menschen, qualitäts‐gerecht zu arbeiten und für die Güte der eigenen Leistungen einzustehen, nicht ersetzen können. Deshalb muß die Erziehung zum Qualitätsdenken eine wichtige Aufgabe der Qualitätssicherung sein.