bluuebunny/crossref_metadata_2025_split huggingface dataset:
Weitergehende Reinigung von Abwässern der Chemischen Industrie mit Hilfe von Aktivkohle
Authors: Eisenächer Karl , Neumann Ulrich 
Published: December 2004

AbstractFurther treatment of waste water in the chemical industry by use of activated carbon. Biological treatment has proved to be no longer adequate for numerous waste water streams emitted by chemical plants. Some of the pollutants entrained by the waste water feature poor biodegradability, and certain compounds even have a detrimental effect on the microorganisms of the activate sludge. Adsorption by activated carbon is one of the potential methods for eliminating such substances. Explanations refer to the physical phenomena of the process. Adsorption may be performed prior to or after biological treatment. Commercial‐scale plants use granular activated carbon and use an intermittent process (fixed bed) or a continuous process (countercurrent adsorber). Possibilities and aspects are exemplified by plants using this process. Operating results are presented. A recent development combines the biological and adsorptive treatment which is based on the continuous admission of powdered activated carbon into the activated‐sludge basin. Results obtained in a demonstration plant will be discussed. Cost‐effective application of this technology is, however, conditional upon reactivation of spent carbon.
Zyklonabscheider zum Trennen von Gas/Feststoff‐Strömungen
Authors: Bohnet Matthias 
Published: December 2004

AbstractCyclone separators for separation of gas/solids flow systems. Cyclones are used for separation of particles of solids from gas flow. Although cyclones have been in industrial use for nearly a century, it is still impossible to completely calculate the flow processes involved. This contribution deals with the theory of the separation process with separation behaviour, limiting particle size, generation of twist, and pressure drop. The article describes optimization of the cyclone by aerodynamic calculations with the separation performance, energy requirement, and investment costs as parameters. The separation performance and the energy requirements of cyclones are largely determined by the mode of construction and the operating conditions. Cyclones used industrially are discussed.
Luftversorgung bei Zweiphasenströmungen
Authors: Schmidt Paul 
Published: December 2004

AbstractAir supply in binary flow. Air is used almost exclusively as the gas in gas/solids flow systems. At low pressure differences of a plant (Δp ≲ 0.5 bar) one speaks of air supply, and at higher pressure differences of compressed air supply. The machines used for supply of the air are fans or compressors. Their characterics should be as steep as possible in order to attain a stable working point in conjunction with the plant. Radial fans are used very frequently because they are inexpensive, reliable, and in some cases passable by the solids; however, they have unfavourable characteristics. Increasing use has recently been made of rotary piston and screw compressors; their characteristics are very steep. Attention must frequently be paid to preparation of the air, and especially drying. The cost of providing the air should be determined as accurately as possible for economic assessments.
Auslegung und Aufbau von Sicherheitseinrichtungen mit Mitteln der Meß‐, Steuer‐ und Regelungstechnik
Authors: Greiner Bernd , Weidlich Stefan 
Published: December 2004

AbstractDesign and construction of safety devices utilizing methods of measurement and control engineering. This article considers a proposed concept for the design and construction of measurement and control devices for the safety of plant with the aim of preventing danger to persons and the environment and damage. Such measurement and control devices are generally employed when primary measures adopted for plant safety, such as safety valves, collection vessels, etc. are not applicable or insufficient by themselves. The concept regards the new sheet no. 3 of the VDI/VDE code draft 2180 „Safety of chemical engineering plant”︁ and proposes a further subdivision of class A into safety classes A0, A1, and A2. Overall, it is possible, on the basis of the measures for raising the availability of measurement and control equipment which are presented in this article, to make selection appropriate to the potential danger involved. The proposed procedure should not, however, be regarded as a rigid scheme but rather as leading to a systematic view and supporting decisions resting on sound operating experience.
Ausbreitung explosibler Gaswolken in der Nähe von Anlagen der Chemischen Industrie
Authors: Kremer Hans 
Published: December 2004

AbstractPropagation of explosive gas clouds in the vicinity of chemical plant. The propagation of large amounts of gases in the vicinity of industrial plant can lead to safety risks and must therefore be estimable in their effect. Methods of both theoretical and experimental simulation are available. Among the computational models, the conventional propagation models used in meteorology are suitable for free propagation. In cases of propagation close to buildings, the relatively straightforwardly applied binomial model is a better choice. Owing to the occurrence of turbulence, the calculations should be supported by wind tunnel studies. An unfavourable system leading to accumulation of large amounts of gas is seen to be a U‐shaped arrangement of buildings with incident flow on the convex side.
Kooperation von Technik und Recht im Hinblick auf die technische Sicherheit
Authors: Nicklisch Fritz 
Published: December 2004

AbstractCooperation between technology and legislation with regard to technical safety. Exploitation of technology involves risks. The state permits this exploitation and must therefore guarantee the necessary safety. In this context, legislation employs undefined legal concepts: „generally recognized rules of technology”︁, „state of technology”︁, „state of science and technology”︁. These standards located at the interface of law and technology raise the question of competence assignment between scientific and technical experts and the authorities and courts. The solution: decision by scientific‐technical experts on the basis of their expertise, coupled with review by the courts in order to establish whether the legal goal of „safety”︁ has been attained. The intermeshing between legal and technical standards is expressed in the technical standards.
Möglichkeiten der elektrochemischen Kohleumwandlung
Authors: Coughlin Robert W. , Kreysa Gerhard 
Published: December 2004

AbstractPossibilities of electrochemical conversion of coal. Coal as a macromolecular organic substance can principally undergo electrochemical conversions. Presently three main directions are under investigation: electrochemical gasification with the formation of hydrogen and carbon dioxide; modification of the chemical composition of coal; and degradation to low‐molecular substances. A historical survey as well as the present state of the art is given and the electrochemical reactions of the coal and their mechanisms are discussed in detail.
Fischer‐Tropsch‐Synthese. Neuere Untersuchungen und Entwicklungen
Authors: König Lutz , Gaube Johann 
Published: December 2004

AbstractFischer‐Tropsch synthesis – Recent studies and Developments. This article surveys some results of recent research and new lines of development in Fischer‐Tropsch synthesis. Most interest is focussed on variants synthesis showing high selectivity of C2‐C4 alkenes or C5‐C20 1‐alkenes or Diesel oil. In the last decade catalysts of improved alkene selectivity have been developed. Also the dependence of selectivity on process parameters such as pressure of hydrogen and carbon monoxide and temperature has been investigated in order to find appropriate conditions of operation for a synthesis of high selectivity. Some preliminary process designs are discussed.
Automatisierung in der Verfahrenstechnik — Möglichkeiten und Grenzen
Authors: Nottebohm Harald 
Published: December 2004

AbstractAutomation in the chemical industry – scope and limitations. Tempestuous developments in semiconductor technology centering upon the microprocessor open up new possibilities of automation in chemical engineering. The traditional appearance of process control rooms is changing drastically. A few video display units with uniform keyboards suffice to monitor and control an extensive chemical plant. In spite of all technical perfection, automation has its limitations wherever unavoidable irregularities require human intervention. This in turn requires that one is in command of both the process and the function of the automatic mechanism.
Transporterscheinungen in Dreiphasen‐Reaktoren mit fluidisiertem Feststoff
Authors: Deckwer Wolf‐Dieter , Schumpe Adrian 
Published: December 2004

AbstractTransport phenomena in three‐phase reactors with fluidized solids. Three‐phase reactors with fluidized solids have a wide range of application. It extends from catalytic hydrogenation, oxidations, polymerizations, and reactions of synthesis gas to coal liquefaction plant and applications in biotechnology. Considerable advantages of these reactors lie in the intense degree of contact between the phases and in their high thermal stability relative to other types of reactors. Pertinent model concepts of fluid dynamics are treated qualitatively, and our present knowledge about transport phenomena within and between the phases is reviewed. Modelling of these reactors is considered in conclusion.
Verfahren zur Entschwefelung von Rauchgas
Authors: Kaminsky Walter 
Published: December 2004

AbstractProcesses for flue gas desulphurization. The continuous high emission of sulphur dioxide from the combustion of fossil fuels is causing increasing damage not only to nature but also to buildings and machinery, especially in industrialized countries. It is possible by desulphurization of the flue gases to reduce the emission of sulphur dioxide by as much as 90%. This can be achieved industrially by dry absorption using activated charcoal or addition of limestone, and by wet processes employing soda, limestone, calcium hydroxide or ammonia as absorbents. The characteristic features of each of the different processes are described. The main residues obtained from these desulphurization processes are gypsum, sulphur, or fertilizer salts, most of which can be recycled. The running costs for such flue gas cleaning processes amount to between DM 0.007 and DM 0.018/kWh depending on location and requirements.
Neuere Sensoren zur Erfassung der klassischen MeßGrößen in der Verfahrenstechnik
Authors: Schneider Hans‐Josef 
Published: December 2004

AbstractNew types of sensors for determination of classical quantities. A description is given of those innovations in the field of flow, pressure, temperature, and level sensors which have appeared during the last ten years, and which have given satisfactory results on use in process engineering. Flow measuring methods are dealt with in particular detail because of their special significance. Finally, the report deals with semiconductor and ceramic sensors.
Neue großtechnische Anwendungen des Reaktionsprinzips der zirkulierenden Wirbelschicht
Authors: Reh Lothar 
Published: December 2004

AbstractNew industrial applications of the circulating fluidized bed. Strongly expanding fluidized beds in the boundary region between fluidized bed and pneumatic conveying, which can achieve a steady state only by recirculation of the solids are of considerable importance for environmental protection because of the high gas flow rates and the high relative velocities possible between gas and solids in performing reactions between gases and fines with an average particle diameter less than 300 μm. Lurgi has utilized the principle of the circulating fluidized bed industrially both in the high temperature regime for the non‐pollutive production of process heat from low‐grade coal in a plant of 84 MW thermal rating and in the low temperature regime for adsorptive, dry purification of fluorine‐containing waste gases from aluminium electrolysis and for dry removal of pollutants from garbage‐burning power plants. This paper reports on the new process.
Einfluß der Wandreibung auf die Dimensionierung von Bunkern — Verfahrenstechnische und statische Gesichtspunkte
Authors: Schwedes Jörg 
Published: December 2004

AbstractInfluence of wall friction on the design of silos – Aspects of process technology and statics.Mass flow and funnel flow are distinguished when considering the discharge of stored bulk solids. In order to cause mass flow to occur, i. e. the complete bunker filling is in motion, hopper walls need to be steep. Conditions close to the outlet are decisive, a large value of wall friction requiring steep hopper walls. For a safe design of bunker walls with respect to mechanical strength, DIN 1055, part 6 is commonly applied; it is currently being revised. From this regulation a strong influence of the angle of wall friction can be inferred, small values of the angle being associated with high horizontal pressures. In case the angle of wall friction depends on pressure and other parameters and safety factors are included there may be a considerable difference between the angle used by a process engineer and by a civil engineer.
Herstellung von Formkörpern mit definierter Porenstruktur
Authors: Hammon Ulrich , Kotter Michael 
Published: December 2004

AbstractFabrication of pellets with defined pore‐size distribution. The fabrication of porous alumina‐pellets of high mechanical strength and with a well defined pore‐size distribution by pelletization and by extrusion is described. Macropores can be introduced through solid material which is vaporized after agglomeration; the content of macropores can thereby be chosen within a rather wide range. The amount of micropores in the pellets can be controlled by thermal treatment (sintering). Mechanical strength is obtained if the primary particles are connected by bridges of solid material, generated from substances dissolved in the liquid which fills the pores before drying. The mechanism and the procedure leading to the formation of porous alumina‐pellets are also applicable if silica or zeolites are to be agglomerated into porous pellets of high mechanical strength.
Auslegung und Dimensionierung eines mechanischen Schaumzerstörers
Authors: Zlokarnik Marko 
Published: December 2004

AbstractDesign and dimensions of a mechanical defoamer. This paper presents a newly developed powerful mechanical defoamer which exploits centrifugal force and, thanks to circular channels, also Coriolis force for destruction of foam. It is incorporated into containers such that the expelled foam concentrate is deflected by the lid without producing fresh foam. Model experiments with three geometrically similar but different sized laboratory models led to dimensionaltheoretically formulated process‐relations of the defoamer for various material systems (five chemical foamers, two biological substrates). Such process‐relations represent a reliable basis for design and dimensions of the defoamer presented, on the one hand, and permit determination of an „intermediate characteristic”︁, having the dimensions of acceleration, which represents the mechanical degradability of the foam.
Methodische Entwicklung verfahrenstechnischer Prozesse
Authors: Blaß Eckhart 
Published: December 2004

AbstractMethodological development of chemical engineering processes. The development of complex systems is especially dependent upon methodologically structured procedures to provide a clear‐cut framework for the application of specialist knowledge and creativity and to develop and exploit the field of possible solutions in order to single out a powerful solution. The method of choice should always be systems engineering. It provides, in relatively abtract and interpretable manner, principles, methods, and proven aids in the form of a system concept, a systems engineering plan of procedure, and project management. A brief introduction to the system concept is followed by application of the systems engineering procedural model to process development. Safety engineering and data acquisition are then considered in detail. Heuristic models are also considered in relation to data acquisition. Expert systems are recommended for setting up collections of information. The article closes with a survey of computer‐aided process development.
Stand und Trends bei der Entwicklung leckfreier oszillierender Verdrängerpumpen
Authors: Vetter Gerhard 
Published: December 2004

AbstractLeakfree oscillating positive‐displacement pumps – state of the art and trends of development. Leak‐ and maintenance‐free oscillating positive‐displacement pumps are very important for avoiding pollution and improving the reliability of plants. Technical progress in the field of hydraulic diaphragm‐ and tube‐pumps for high pressures are explained. The actual data (pressure, efficiency, temperature) and experience with different fluids are surveyed. The various hydraulic control systems, the diaphragm design, and methods for rupture‐control are compared. Further development trends are explained.
Auslegung von Industrie‐Rührwerken
Authors: Kipke Klaus 
Published: December 2004

AbstractDesign of industrial agitators. The chemical engineering and mechanical design of industrial agitators has meanwhile developed into a highly complex process. Energy‐saving constraints no longer allow agitator scale‐up with P/V = constant while deriving the mechanical dimensions purely in terms of the torque. A clear classification of the various goals of agitation into the basic components with the corresponding scale‐up rules proves to be useful. If due attention is also paid to the various stirrer geometries then it is possible, with computer aid, to design an optimum agitator for a given purpose – this approach involves considerable effort but is necessary for proper design. A well‐conceived modular system and the influence of DIN standardization also preclude any uneconomical proliferation of agitator types without seriously limiting the flexibility demanded by the user.
Entwicklung des Trenndüsenverfahrens zur Uran‐Anreicherung
Authors: Becker Erwin Willy 
Published: December 2004

AbstractDevelopment of the nozzle separation process for enrichment of uranium. In the nozzle separation process an enrichment of 235U is achieved by extremely high centrifugal forces in a curved flow of UF6 diluted with a light gas. In Brazil a cascade section consisting of 24 nozzle separation stages has been constructed and has been in operation since late 1985. To produce nozzle separation systems with extremely small characteristic dimensions permitting plant operation at atmospheric pressure, a manufacturing process has been developed which relies on combined X‐ray lithography and microgalvanic deposition (LIGA‐technology). Using this technology the prototype separation stages constructed at the Karlsruhe Nuclear Research Center enable commercial nozzle separation plants with capacities of up to 3 Mio. SWU/year to be realized.
Expertensysteme — Aufbau und Anwendungsgebiete
Authors: Trum Peter , Iudica Norberto R. 
Published: December 2004

AbstractExpert systems – structure and fields of application. Expert systems are programs for solving problems in narrow fields of application, which demand the competence of an expert. These systems, which process not only data but primarily knowledge, have attracted considerable interest in recent years. This contribution explains the principal characteristics and the mode of operation of expert systems, and dilineates their potential applications. Moreover, the approach adopted in the development of expert systems is briefly considered.
Brauchen wir Stoffaustausch‐Maschinen?
Authors: Mersmann Alfons , Voit Harald , Zeppenfeld Rolf 
Published: December 2004

AbstractDo we need mass transfer machines? In contrast to mass transfer apparatus, the throughput of the phases as well as volumetric mass transfer rates in mass transfer machines are increased by moving machine parts (especially rotating and pulsating). This increase depends on the centrifugal acceleration expressed as the parameter z and the specific power input ε. This paper shows the dependence of the volumetric interfacial area, the gas‐side and liquid‐side mass transfer coefficients, and the volume ratio of machines and apparatus on the parameters z and ε. Furthermore, information is given about the increase of the specific power input ε of different mass transfer equipment with rising z.
Auskleiden und Beschichten von Apparaten mit Kunststoffen
Authors: Rimanek Rainer 
Published: December 2004

AbstractLining and coating of chemical apparatus with plastics. The object of this report is to provide a concise survey of applications for plastics in the lining and coating of steel constructions to avoid corrosion, erosion, and caking. Special attention is paid to the field of chemical apparatus and pipeline construction where, due to the requirements in question, the layer thicknesses amount to several millimetres.
Prognosen in der chemischen Technik
Authors: Collin Gerd 
Published: December 2004

AbstractForecasts in the chemical industry. Forecasts of the energy demand in the Federal Republic of Germany for 1985 predicted figures which were, in some cases, more than 100% higher than the actual consumption figures, due among other things to an unforeseen decrease in specific energy consumption, e. g. in the chemical industry to about half of that in 1960. Since 1973 the overall energy consumption in the chemical industry has remained almost unchanged at some 15 million t/year coal equivalents in spite of increased production. In future forecasts, these possible divergences between economic growth and energy consumption will have to be given far greater attention. In 1977/1978 forecast, figures were calculated for the material flow from the raw material to the end products in selected fields in the chemical industry by means of a simulation model. Some of these forecasts show satisfactory agreement, while some of them deviate to a greater extent from the actual production figures, partly due to unexpected drastic changes in import quotas for some basic chemicals and intermediates.
Wirtschaftlichkeit als Kriterium für die Entwicklung, Auslegung und Auswahl von Apparaten und Maschinen für Prozeßstufen
Authors: Nill Bernhard 
Published: December 2004

AbstractEconomy as a criterion for development, design, and choice of equipment and machines for process steps. The object of this paper is to show how a supplier of individual machines can influence the total costs of a chemical processing plant. This influence is quantified using actual examples based on the development of a product range, the optimizing and matching together of mechanical and thermal separation processes, and the selection of the most suitable types of equipment. Studies show that the products and services of an equipment manufacturer can influence substantially more than just capital investment costs and interest charges with their consequent effects on the annual running costs of a plant. It is possible to reach more economical solutions for important stages in a manufacturing process if the plant designers and the equipment manufacturers work closely together. A too tightly specified enquiry can prevent a manufacturer from offering the technically and economically optimized solution. By involving equipment manufacturers and correctly using their know‐how one can tap a substantial potential for the reduction of plant running costs.
Prüfmethoden für Kunststoffbehälter in der chemischen Industrie
Authors: Hessel Joachim 
Published: December 2004

AbstractMethods of testing plastic vessels in the chemical industry. Methods are discussed for the testing of vessels made of thermoplastics and glass fibre reinforced plastics. Technical notes, guidelines and standards (DVS, VDI, DIN) describe methods of ensuring the quality of new containers. New testing methods have to be employed for equipment that has long been in use in order to provide subsequent confirmation of suitability. An appropriate concept is presented.