bluuebunny/crossref_metadata_2025 huggingface dataset:
Gewinnung von Öl durch Schwelen von Ölschiefer und Teersand als Beitrag zur Energieversorgung
Authors: Rammler Roland , Weiss Hans‐Jürgen , Bußmann Alfons , Simo Thomas
Published: December 2004

Nach einem weltweiten Überblick über die wichtigsten Lagerstätten von Ölschiefer und Teersand werden die derzeitigen Aktivitäten in der UdSSR, in China und Canada auf dem Gebiet der industriellen Gewinnung von Schieferöl und von Bitumen aus Teersanden in großen Zügen beschrieben. Anschließend werden die heute zur Diskussion stehenden Großprojekte zur Erzeugung von synthetischem Rohöl auf der Basis dieser Ausgangsstoffe aufgezeigt.

Arbeitsweise und Entwicklungsstand der modernen Verfahren zur Schwelung von Ölschiefer werden dargestellt, ebenso das Arbeitsprinzip der bereits großtechnisch in Anwendung stehenden Heißwasserextraktion von Teersand. Genauer eingegangen wird auf die Arbeitsweise des Lurgi‐Ruhrgas (LR)‐Verfahrens und dessen besonderes Merkmal, daß der ausgeschwelte Rückstand als fester Wärmeträger im Kreislauf geführt wird. Es folgen Angaben über das Durchsatzpotential dieses Verfahrens. Die charakteristischen Reaktionen, welche die Qualität der LR‐Produkte (Öl, Gas, Rückstand, Abgas) beeinflussen, werden dargestellt. Typische Qualitäten für Öl und Gas auf Basis eines Ölschiefers und eines Teersands werden angegeben.

Für die Weiterverarbeitung der Kondensatströme aus dem LR‐Verfahren wird ein Weg gezeigt. Dieser besteht aus Feststoffabscheidung, destillativen Trennungen und je einer Hydrierung für die Naphtha‐ bzw. Ölfraktion. Diese Verarbeitungsschritte ergeben ein „Syncrude”︁, das mit Rohöl gemeinsam in konventionellen Raffinerien weiterverarbeitet werden kann. Für die selbständige Weiterverarbeitung des Syncrude zu handelsüblichen Endprodukten werden Beispiele gegeben.
Vakuumpumpen für die chemische Verfahrenstechnik — Arbeitsweise und Betriebskosten
Authors: Hupe Adolf
Published: December 2004

Vakuumprozesse in der chemischen Industrie erfordern überwiegend Saugdrücke, die zwischen dem Atmosphärendruck und etwa 10−2 mbar liegen. Der hier zu behandelnde Vakuumbereich umfaßt also fünf 10er‐Potenzen. Die Saugvolumenströme liegen zwischen 1 und 100 000 m3/h und überdecken damit ebenfalls fünf 10er‐Potenzen. Diese Größenordnungen lassen verständlich werden, daß es kein einzelnes Pumpsystem geben kann, das im gesamten Bereich optimal einzusetzen ist, zumal auch noch untersucht werden muß, ob die für bestimmte Pumpenbauarten erforderlichen Schmiermittel, Abdichtungs‐, Kühl‐ und Verdrängungsflüssigkeiten oder in anderen Fällen die anzuwendenden Treibflüssigkeiten, Treibdämpfe oder Treibgase mit dem verfahrenstechnischen Prozeß verträglich sind. Entscheidend ist auch, welche finanziellen Belastungen man mit den verschiedenen Pumpsystemen für die Investitionen hinsichtlich Kapitalbindung, Abschreibung und Zinsen, für die Montage, für die Betriebshilfsstoffe, für den Energieverbrauch, für die Bedienung sowie für Wartung und Reparaturen zu tragen hat.
Entstaubungsanlagen für Elektroniederschachtöfen
Authors: Maier Hans , Winter Klaus
Published: December 2004

Elektroniederschachtöfen sind bei der Herstellung von Calciumcarbid, Ferrolegierungen, Silicium und Silicium‐Legierungen im Einsatz. Bei diesen Reduktionsprozessen müssen große Mengen an heißen, staubbeladenen Abgasen abgeführt und gereinigt werden. Die Staubquellen und die Entstaubungssysteme werden beschrieben, für die Auswahl von filternden Abscheidern werden Hinweise gegeben. Die Aufwendungen für die Entstaubung von Elektro‐Reduktionsöfen können durch Nutzung der in den Abgasen enthaltenen Energie vermindert werden. Allerdings sind die für die Abwärme‐Rückgewinnung notwendigen Investitionen zur Zeit noch unwirtschaftlich.
Beseitigung von Abfällen in einer Sonderabfall‐Deponie
Authors: Barth Erhard
Published: December 2004

Bei der Einrichtung und beim Betrieb von Sonderabfall‐Deponien ist größte Sorgfalt nötig, da die Öffentlichkeit sehr empfindlich auch auf geringfügige Beeinträchtigungen der Umwelt in der Umgebung derartiger Deponien reagiert. Am Beispiel der Sonderabfall‐Deponie Malsch südlich von Heidelberg wird über alle zu beachtenden Gesichtspunkte berichtet, beginnend mit den geologischen Voraussetzungen, den Dichtungsmaßnahmen und der Kontrolle der Deponie. Im Hauptteil werden u. a. das Antragswesen, die Ausrüstung und der Betriebsablauf behandelt. Bisher gab es in der Sonderabfall‐Deponie Malsch keine gravierenden Vorkommnisse.
Anwendung der Unifac‐Methode zur Vorausberechnung von Extraktionsparametern
Authors: Tegtmeier Uwe , Misselhorn Klaus
Published: December 2004

Die Auslegung eines Extraktionsprozesses erfordert neben der Kenntnis von verfahrenstechnisch zu beeinflussenden Parametern vor allem eine klare Definition der zu verwendenden Lösungsmittel und der hiermit verbundenen Prozeßdaten. Als wichtige Größen sind hierbei das Löslichkeitsverhalten der koexistierenden Phasen und die Selektivität des Solvens zur übergehenden Komponente zu nennen. Die Unifac‐Methode, als eine Inkrementenmethode mit einer bereits großen Anzahl zugänglicher Parameter, bietet die Möglichkeit, Flüssig/Flüssig‐Phasengleichgewichte und Verteilungskoeffizienten in Mehrkomponentensystemen auch ohne Kenntnis der experimentellen Daten vorauszuberechnen. In diesem Aufsatz wird anhand von ternären Wasser/n‐Alkohol‐Systemen der Grad der Genauigkeit der Unifac‐Rechenmethode dargestellt.
Neue Wege bei der flotativen Aufbereitung und Abwasserreinigung in der chemischen Industrie
Authors: Zlokarnik Marko
Published: December 2004

Die Flotation hat sich in der chemischen Industrie als ein Trennverfahren für das System fest/flüssig bisher noch nicht durchgesetzt. In der vorliegenden Arbeit wird versucht, dafür eine Erklärung zu finden. Gleichzeitig werden Möglichkeiten aufgezeigt, die die Flotationstechnik zur Werkstoff‐Rückgewinnung und Abwasserreinigung in der chemischen Industrie attraktiv machen könnten. Nach Hinweisen auf die Phänomene, deren sich die Flotationstechnik bedient, werden die verfahrenstechnischen Aspekte dieser Technik bei der Erzund Kohleflotation bzw. bei der mechanischen Abwasserreinigung besprochen. Es wird eine rührerlose Flotationszelle vorgestellt, die speziell für die Belange der chemischen Industrie entwickelt worden ist. Abschließend werden einige Flotationsaufgaben, die mit einer Laborausführung dieses Zellentyps durchgeführt worden sind, vorgestellt und besprochen. Sie zeigen, daß die Flotationstechnik bei vielen Trennaufgaben in den Stoffsystemen fest/flüssig und flüssig/flüssig eine günstige Alternative zu den klassischen Trennverfahren sein kann und sie daher künftig bei entsprechenden Trennproblemen (Teilchengröße ≤ 100 μm, Feststoffgehalt ≤ 20 g/l) in Erwägung gezogen werden sollte.
Grenzflächenforschung und Verfahrenstechnik
Authors: Nassenstein Heinrich
Published: December 2004

Die Arbeit behandelt Fortschritte der Grenzflächenfor‐schung und ihre Bedeutung für die Verfahrenstechnik. Auf den Gebieten: Feste Grenzflächen, Flüssige Grenzflächen und Disperse Systeme werden insbesondere neue Untersu‐chungsmethoden, neue Erkenntnisse und ihre Anwendung beschrieben. Der Bericht stützt sich maßgeblich auf Ergebnisse der Arbeit des Ausschusses „Grenzflächen”︁ der GVC.
Rohrfertigung für den Reparaturbereich
Authors: Lang Christian , Konrad Otto , Hoffmann Dieter
Published: December 2004

Die in den letzten Jahren vollzogenen Veränderungen der Rohrfertigung werden besprochen, die rationellere Reparaturen ermöglichen, ohne die für die Instandhaltung not wendige Flexibilität und schnelle Reparatur‐Abwicklung zu beeinträchtigen. Voraussetzung dafür ist die Verlagerung der Rohrleitungsarbeiten in Werkstätten. Nur hier kann manuelle Arbeit, wie z. B. die Handschweißung, auf ein Minimum reduziert und durch maschinelle oder halbmaschinelle Schweißverfahren ersetzt werden. Der Einsatz moderner Biegemaschinen zum Abwickeln der Rohre ist wirtschaftlicher als der Einschweißbogen. Das maschinelle Aushalsen oder die Verwendung von mechanisch vorgefertigten Stutzen ermöglicht eine optimale Schweißnahtvorbereitung für Rohrabzweigungen. Die weiteren Rohrarbeiten, soweit noch erforderlich, erfolgen an speziell dafür eingerichteten Arbeitsplätzen.
Meß‐ und Regeltechnik in Chemieanlagen unter sicherheitstechnischen Aspekten
Authors: Hartmann Edmund
Published: December 2004

Der Einfluß der Leittechnik auf die Sicherheit von Chemieanlagen wird beschrieben. Dabei wird auf die Anforderungen an die Einrichtungen der Leittechnik in sicherheitstechnischer Hinsicht sowie auf deren Einstellung, Anordnung und Überbrückung eingegangen. Es wird dargelegt, daß unter bestimmten Voraussetzungen Einrichtungen der Leittechnik anstelle von herkömmlichen Sicherheitseinrichtungen unter Aufrechterhaltung der gleichen Sicherheit eingesetzt werden können. Auch Überlegungen in Hinblick auf eine effektive Prüfung und auf sinnvolle Prüftermine werden angestellt. Einige sicherheitstechnische Grundgedanken bei der Planung von Chemieanlagen gehen diesen Darlegungen voraus.
Methoden und derzeitiger Kenntnisstand für Auslegungen beim Mischen von Feststoffen
Authors: Müller Walter
Published: December 2004

Für Auslegungen zu Verfahren des Feststoffmischens interessieren hauptsächlich die notwendige Leistung und die Mischzeit. Die für den Werkzeugwiderstand verantwortliche Reibung hängt bei einem Schüttgut außer von Parametern wie Kornfeinheit und ‐rauhigkeit auch vom Verdichtungszustand des Materials und in starkem Maß von geometrischen Gegebenheiten ab. Weil Grundlagen‐Untersuchungen sowohl zur Leistung als auch zur Mischzeit, in die notwendigerweise Fragen der Maßstabsvergrößerung miteinbezogen sein müssen, außerordentlich aufwendig sind und deshalb nur in ungenügendem Maß vorliegen, fehlen der Planung geeignete Unterlagen. Sie ist in hohem Maß auf Erfahrungen von Apparateherstellern angewiesen. In dieser Arbeit soll allgemein, insbesondere aber anhand einiger wichtiger Mischverfahren, der Kenntnisstand umrissen werden.
Biologie der Methan‐Bildung
Authors: Sahm Hermann
Published: December 2004

Es ist seit langem bekannt, daß überall in der Natur, wo organisches Material unter anaeroben Bedingungen mikrobiell abgebaut wird, Methan entsteht. Diese Fähigkeit anaerober Bakterien, organische Substanzen zu Methan und Kohlendioxid abzubauen, wird im großtechnischen Maßstab seit über 50 Jahren zur Stabilisierung von Klärschlamm genutzt. In jüngster Zeit konnte nachgewiesen werden, daß bei diesem Prozeß mindestens drei verschiedene Gruppen von Bakterien beteiligt sind. Bei dieser Abbau‐ bzw. Nahrungskette werden zunächst die verschiedenen organischen Verbindungen zu niedrigen Alkoholen, Fettsäuren, Wasserstoff und Kohlendioxid von einer Bakteriengruppe abgebaut. Die zweite Mikroorganismen‐Gruppe setzt diese Alkohole, Säuren etc. weiter zu Essigsäure, Wasserstoff und Kohlendioxid um, welche dann von den Methan‐Bakterien als Substrat verwertet und in Methan und Kohlendioxid (Biogas) umgewandelt werden.
Schwimmende Produktionsanlagen für die Rohstoffgewinnung im Meer
Authors: Amann Hans
Published: December 2004

Der zunehmende Trend, Rohstoffe wie Öl, Gas und Mineralien aus Offshore‐Lagerstätten zu gewinnen, führt zur Benutzung von schwimmenden Plattformen auf hoher See. Die prozeßtechnischen Aspekte der Offshore‐Gewinnung von Öl und Gas werden diskutiert. Da sich die prozeßtechnischen Probleme leichter bewältigen lassen, wenn die Methoden an Offshore‐Bedingungen angepaßt sind, erfordert die Lösung struktureller und betriebstechnischer Probleme bei Tiefsee‐Plattformen mehr Entwicklungsarbeit bei der Maßstabsvergrößerung und besonders kostspielige Versuche im technischen Maßstab.
Entwicklungstendenzen metallischer Werkstoffe aus der Sicht der Verwendung im Chemieanlagenbau
Authors: Gräfen Hubert
Published: December 2004

Developments of metallic materials in view of their use for chemical plants. The demands placed on materials of construction for chemical plants are becoming more and more stringent due to the steady increase in mechanical, thermal, and chemical loading. Molten metallurgical improvements, alloying steps, new methods of plastic deformation and heat treatment, and facilitation of workability are implemented in attempts to optimize the properties of construction materials and to achieve better adaptation to the service conditions. Progress achieved by research and developments during recent years in the above mentioned field is apparent in practical applications of some groups of materials which are important for construction of apparatus; these are high‐strength fine grained steels, high‐alloyed ferritic and austenitic stainless steels, as well as duplex steels. Moreover, the improvements – especially in corrosion restistance – are considered which can be obtained by special melting techniques and new fabrication processes. In addition, the advantages of electroslag remelting (ESR) and powdermetallurgical fabrication of semi‐finished products of corrosion resistant alloys and the possibilities of hotisostaticpressing (HIP) of structural components are discussed.
Metallsalz‐Extraktion
Authors: Marr Rolf , Bart Hans‐Jörg
Published: December 2004

Solvent extraction (SX). SX is widely used to separate metals from diluted leaching liquors, wastes, and effluents. The composition of the organic phase has great influence in this type of extraction with chemical reaction. Some trends and rules can be given. Another major problem is the aqueous phase. A systematic study is undertaken to up‐date the parameters which are changing with aqueous phase composition. Step‐by‐step development of a process is shown.
Erfassung, Beschaffung und Montage von Rohrleitungsteilen
Authors: Diegelmann Ewald
Published: December 2004

Assessment, acquisition, and assembly of pipe components. Pipe technology accounts for ca. 30 to 35% of the planning of chemical plant and refineries. The reason for this high proportion lies in the numerous possibilities of variation. Each part must be defined, assessed and executed. The programme system developed consists of an assembly of several individual programmes which utilize available data. The overall procedure, from specification to assembly, is performed or supported by this programme system. The “general text system” (ATS) stores all pipe texts and pipe classes in several languages. With the aid of the “Lurgi piping macro‐system” (LUROMAK) the piping components are processed on the basis of flow charts, assembly plans and isometric drawings. The materials determined are transformed into buying information by the “execution system” (DISPO). Registration of material entering and leaving stores in the “assembly organization system” (MOS) permits work preparation for assembly on the basis of the resulting stocks. It is also possible to assess the progress of assembly and to prepare costing information. The continuous processing of piping is permitted by a systematic standardization and classification, accomplished in particular by uniform definition of piping components in the ATS programme system.
Automatisierte Analytik zur Überwachung und Steuerung von Versuchsanlagen
Authors: Hachenberg Horst
Published: December 2004

Automatic analysis for monitoring and control of pilot plant. The utility of automation of gas chromatography GC and high performance liquid chromatography HPLC for routine tasks in research is demonstrated with the aid of examples. Particular attention is paid to problem‐oriented and economically contained analytical instruments and to the constant availability of analytical data.
Dichtstromförderung
Authors: Krambrock Wolfgang
Published: December 2004

High density pneumatic conveying. In distinguishing between high density pneumatic conveying and low density conveying it is insufficient to merely use the solids loading to characterize the various flow states. Less ambiguous classification is possible only on the basis of the diagram of state of pneumatic conveying. Most flowable bulk solids can be transported through normal smooth‐walled piping in the high density mode with normal conveying equipment. In contrast, fine‐grained products in particular tend to adhere to the wall and form blockages. Paying due attention to the differing flow properties of various bulk solids and to the mechanisms of blockage formation and clearance, various new conveying techniques and piping types have been developed in recent years, permitting in some cases the transport of adhering, abrasive, and attrition‐sensitive materials. Since conveying pressures up to about 6 bar are usual in the high‐density regime, various combinations of pressure vessels are primarily used for feeding the bulk solids into the conveying pipes. The advantages of conventional, and also special high‐density conveying systems are discussed with the aid of examples.
Hydrierende Vergasung von Kohle – Neuere Betriebsergebnisse
Authors: Fladerer Rolf , Schrader Lothar
Published: December 2004

Hydrogasification of coal – recent operational results. The Rheinische Braunkohlenwerke AG has built and has been operating a semi‐technical pilot plant for hydrogasification of coal in a fluidized bed. The objective is to develop a coal gasification process with hydrogen for producing directly substitute natural gas. Between 1976 and 1981, the semitechnical pilot plant having a capacity of 100 kg C/h was operated for about 22,900 h under test conditions, more than 9,500 h of which were under gasification conditions. During this time, approximately 1,400 metric tons of dry coal were gasified. The longest coherent operational phase under gasification conditions was 748 h in which 86.4 metric tons of dry lignite were gasified. Carbon gasification rates up to 82% and methane contents in the dry raw gas (free of N2) up to 48 vol.‐% were obtained. A detailed evaluation of the test results provided information on the influence of additional parameters on the efficiency dates of the gasifier and a considerable refining of the results obtained previously. Moreover, several components were tested for which no operational experience had previously been gained; these were newly developed devices, e. g. the inclined tube for feeding coal into the fluidized bed. Within the framework of scale‐up work to large‐scale coal gasification plants, a pilot plant having a capacity of approximately 6 t C/h will be commissioned in late 1982.
Mechanismus der katalysierten Synthese von Kohlenwasserstoffen
Authors: Sachtler Wolfgang M. H.
Published: December 2004

On the mechanism of the catalysed synthesis of hydrocarbons. Recent results by independent research teams prove that, in hydrocarbon synthesis over metal catalysts in a reducing atmosphere, the dissociative adsorption of CO is of considerable importance. On the catalyst surface the two fragments, Cads and Oads, react swiftly with hydrogen to CHx,ads and H2O respectively. CHx,ads can be either hydrogenated to methane or incorporated in growing chains. This process may be visualized as a cis insertion of a carbene CH2,ads in a metal‐alkyl bond. In the steady state the catalyst surface is predominantly covered with COads, only a small fraction of the surface atoms carrying growing alkyl groups. These have been detected by 13C labelling as well as by IR spectroscopy.
Verfahrenstechnik der aeroben Abwasserreinigung. Entwicklungen und Trends
Authors: Zlokarnik Marko
Published: December 2004

Chemical engineering of aerobic waste water treatment – developments and trends. The present article deals with chemical engineering problems encountered in biological waste water treatment, as seen in research reports published during the last 5 to 10 years. It is seen that important advances in our biological and engineering knowledge of the biological degradation of organic wastes, relating to residence time distribution, concentration of biomass, and the temperature in the activation process have not been given sufficiently consistent attention in practice. Controversial views and possible solutions are indicated. Immobilization (especially with activated charcoal as carrier) offers certain advantages for raising the concentration of biomass in the activation space, this also facilitating separation of the biomass from the purified water. Flotation could offer an alternative. Disposal of the excess activated sludge is nowadays accomplished largely by anaerobic fermentation (bioconversion); the engineering of this step was developed in the 1930's and should be updated at the earliest possible opportunity. This would enhance the appeal of the process because the energetic potential of the biomass could then be fully utilized.
Neuere Entwicklungen bei Härtbaren Formmassen. Werkstoffe – Anwendungen – Verarbeitungs‐Technologien
Authors: Jellinek Karl , Schöunthaler Waldemar , Niemann Klaus
Published: December 2004

New developments in thermosetting moulding compounds – Materials – Applications – Processing technology. Thermosetting moulding compounds are defined as raw materials manufacturing plastic parts under the influence of pressure and heat, mainly by compression, transfer and injection moulding which are formulated in workable form from thermosetting reactive resins, fillers, reinforcers, and other additives. The present article will consider only moulding compounds in granular form whose processing to moulded parts is mainly automated and which represent a group of plastics clearly distinct from pasty or liquid thermosetting moulding materials.
Entwicklungen in der Technologie zur Herstellung von Brennstoffen aus kommunalen Abfällen
Authors: Kaster Bernhard
Published: December 2004

Developments in the technology of fuel production from municipal waste. Various methods have been developed in recent years for the production of fuel from municipal waste in the USA and in Europe, and some of them have been tested on a large scale. They utilize mainly machines employed in mechanical work‐up and proven process steps developed specifically for the recovery of materials from municipal waste. Starting from the demands placed on the fuels the present status in Europe and the Federal Republic of Germany is illustrated with the aid of selected examples. The paper reports experimental results, operating experience, measures adopted to optimize the process engineering and to improve the fuel quality. It is not yet possible on the basis of the results obtained so far to estimate whether the production of fuels from waste will become accepted practice in Germany. It will be decisive whether the quality of the fuel can be optimized such that the limiting pollutant levels can be met without any need for flue gas scrubbing and whether longterm economic marketing of the fuel products is feasible.
Aufgaben des Werksarztes in der chemischen Industrie
Authors: Thiess Alfred M.
Published: December 2004

Tasks of the company doctor in the chemical industry. The tasks of the company doctor are stipulated in paragraph 3 of the works doctor, safety engineers, and other specialist staff for works safety act (ASIG) of December 12, 1973. However, long before this act was passed, responsible companies, especially in the heavy chemical industry, employed factory doctors. In the present industrial and technical age, the health care of employes is of prime importance in a modern company; health care is not merely demanded by social ethics but remains a responsible managerial task. The activities of the company doctor extend far beyond the requirements specified in the above act (ASIG) and also include preventative medicine. The participation of company doctors in national and international occupational medicine committees, e. g. in company inspectorate, professional organizations, ministry of employment, federation of the chemical industry, working committee, CEFIC, EC, WHO, etc.
Trennen von Gasgemischen durch Adsorption
Authors: Mersmann Alfons , Münstermann Ullrich , Schadl Josef
Published: December 2004

Separation of gas mixtures by adsorption. Gas mixtures are separated primarily by absorption and rectification. Rectification requires at least (v + 1)‐fold of the enthalpy of the distillate as heat energy (v is the reflux ratio). In the case of absorption, the resulting solution is frequently subjected to thermal regeneration with the energy requirement depending inter alia on the boiling point of the solvent. In view of the high energy requirements of these processes and the development of new adsorbents, possibilities of separating by adsorption with subsequent regeneration of the adsorbents, above all by change in pressure, are investigated. The separation of gas mixtures in adsorber beds (e.g. molecular sieves, silica gel, activated charcoal and coke, or alumina) depend upon various separating effects: steric effects, equilibrium effects, kinetic effects. A survey is given of proposed and practical industrial separation processes utilizing adsorption.
Ethanol als Rohstoff für die chemische Industrie
Authors: Swodenk Wolfgang
Published: December 2004

Ethyl alcohol as raw material for the chemical industry. The oil crisis has awakened consciousness of the forseeable end of oil supplies and evoked an intensified search for alternative sources of raw materials. Aside from coal, naturally growing raw materials are attracting renewed attention. Ethanol is frequently discussed as a potential key product for further chemical use. For a realistic assessment of the potential of ethanol as a chemical raw material, model cases are considered in which the availability of the naturally growing raw materials for ethanol, the necessary investments for its production and further use, and the financial competitiveness of ethanol are investigated as main criteria.
Das mechanische Entfeuchten von Filterkuchen
Authors: Redeker Detmar , Steiner Karl‐Heinz , Esser Ulrich
Published: December 2004

Mechanical demoisturing of filter cakes. Flow and centrifugal demoisturing and pressing are the principal methods of mechanical demoisturing of filter cakes. In flow demoisturing cracking has a detrimental effect. Compressibility, flow and centrifugal demoisturing can be completely described mathematically in dimensionless form. The limitations of mechanical demoisturing are presented for individual examples of apparatus.
Neue apparative Entwicklungen bei Filterzentrifugen
Authors: Hultsch Günther
Published: December 2004

New equipment developments in filter centrifuges. Industrial filter centrifuges are used for solid throughputs from ca. 0.01 to 250 t/h per machine. The specific filtration resistance of the solids to be separated likewise covers a range of ca. 1 :25 000. In addition to the enormous range of physical properties and mass flows, a wide variety of demands is placed on the chemical resistance of the materials of construction and the safety of the plant. These demands led to the development of a wide range of filter centrifuges, the most important types of which are first surveyed from a chemical engineering standpoint. There follows an account of the principal characteristics of recent types and the development of various details.
Probleme bei der Filtration unter extremen Gas‐ und Staubbedingungen
Authors: Schulz Reinhard
Published: December 2004

Filtration problems under extreme conditions. Filtering separators belong to the high‐performance separators and their significance in dust extraction techniques is increasing. They are distinguished by offering almost any desired efficiency of separation which property, on use of appropriate filter media, is also preserved under fluctuating working conditions with regard to dust content in the crude gas, size of the dust particles to be separated, and the rate of gas flow. In order to exploit these advantages also under extreme conditions of gas and dust attempts were made in recent years to extend the operating range by the development of new filter media. Among the applications deserving mention are the fly‐ash collection in coal‐fired power plants and the dust separation under high temperatures for new power technologies. The present state of the art and experience gained so far are presented.
Entwicklungen zur Flugstrom‐Vergasung nach dem Koppers‐Totzek‐ und dem Prenflo‐Verfahren
Authors: Schmidt‐Traub Henner , Pohl Hans Christoph
Published: December 2004

Developments on entrained‐flow gasification using the Koppers‐Totzek and the Prenflo process. Many years of operating experience have permitted continuous improvements in capacity and availability of entrained‐flow gasification plant applying the Koppers‐Totzek process. Further increases in capacity and economy, in particular where poorly reactive coals are to be gasified, will be achieved using the pressurized Prenflo process. Gasifier development is being supplemented by the development of complementary equipment, such as dry coal‐dust feed, material flow metering, and process automation. Closed wash water systems and other processing stages serve to improve environmental protection. The combination of pressurized gasification with a power station permits economical power generation with a high degree of efficiency and minimal environmental impact. Individual problems connected with pressurized gasification are being researched in a 48 t/d pilot plant.
Reaktionstechnische Grundlagen zur Auslegung und zum Betrieb von Bioreaktoren, Teil 2
Authors: Schügerl Karl
Published: December 2004

Reaction engineering fundamentals relating to design and operation of bioreactors, Part 2. Part 1 of this contribution treated balances, thermodynamic data and models. The present part 2 considers the following: dynamic behaviour of combined reactor models, reactor observability and controllability, process design (optimum performance), optimal feed‐back control, and the feasibility of these points. In the case of biological systems the present limits of measured data acquisition have been reached. New measuring instruments will have to provide more information about the cells and about the dynamic behaviour of the cell‐reactor system.
Umweltschutz bei der großtechnischen Kohlenutzung
Authors: Allhorn H. , Huber W. , Birnbaum U.
Published: December 2004

Environmental protection at industrial scale utilization of coal. In view of the expected increase in consumption of coal and coal products to satisfy energy demands, a consideration of emissions released from coal mining and utilization facilities is of particular interest. Starting from a discussion of basic technical principles, possible sources of emission are established for the most important processes with electricity generation and coal refining playing major roles. A study of possible measures to reduce emissions, as well as emission data available in the literature, indicate future alternative courses of action when adopting various methods of utilization.
Verfahren zur Herstellung von Solarsilicium
Authors: Aulich Hubert Alfred , Schulze Friedrich‐Wilhelm , Grabmaier Josef Gabriel
Published: December 2004

Production of solar silicon. Economic exploitation of solar energy using solar cells made of crystalline silicon is dependent upon a considerable drop in the cost of the silicon raw material which is nowadays produced by standard methods of the semiconductor industry. New procedures for producing less expensive solar silicon can be divided into four groups characterized by different physico‐chemical purification techniques: (1) reduction of volatile Si‐H‐Cl compounds; (2) purification of technical grade silicon (98–99%); (3) reduction of hexafluorosilicates; (4) reduction of silicon dioxide. Among the ten solar silicon processes under discussion, the purification of technical grade silicon and the carbothermal reduction of silicon dioxide have the greatest scope for cost reduction; however, it remains to be established whether the necessary purity can be achieved on an industrial scale.
Anwendung elektronischer Rechner in der Chemischen Technik
Authors: Lübbert Andreas
Published: December 2004

Use of computers in chemical engineering. It is shown by various examples from three directions of development how modern microelectronics, especially microcomputer technology, can be used effectively in chemical engineering applications. These are applications of microprocessors in complicated measuring tasks, the distribution of computing power in computer networks and the use of specialized processors.
Aufgaben der Produktionsleitebene in der chemischen Industrie
Authors: Hofmann Winfried
Published: December 2004

The plant management functions in chemical industry. The information flow can be structured by a layer model, comprising the plant management layer, the process control layer, and the field layer. The higher company management layer issues production orders which are detailed at the plant management layer with the aid of a formulation; amounts of materials required, equipment, personnel, and laboratory measurements are assigned as a prerequisite for production. These tasks are described in detail, the flow of information between the adjacent layers indicated, and the layer structure of other business units briefly considered.
Erforschung von Schadenfeuern flüssiger Kohlenwasserstoffe als Beitrag zur Sicherheit von Chemieanlagen
Authors: Schönbucher Axel , Brötz Walter , Balluff Christoph , Göck Dietmar , Schieß Norbert
Published: December 2004

Investigation of hazardous fires of liquid hydrocarbons as contribution to the safety of chemical plants. This article illustrates the danger potential of hazardous fires, such as pool‐and tank fires in chemical plants. The importance and the role of fluid dynamic organized structures for the combustion processes are presented. Experimental methods used for the visualization of these organized structures are also explained. The influence of such structures on the safety data, burning rate, maximum pool fire diameter, flame height and flame tilt, and the total radiative power is dealt with in detail. The point source model and the solid flame radiation model are discussed for calculation of the distance‐dependent irradiance of a pool fire. A new model, the parcel‐radiation model, considers the radiation of hot spots, soot parcels, and the effect of radiation blockage by cooler, unburnt fuel parcels. Application of the parcel‐radiation model leads to a calculated maximum irradiance of „E≈ 4 W/cm2, which is verified experimentally for most pool fires with diameters > 14 m. These irradiances are three times smaller than the values calculated by the solid flame radiation model. The consequences for safe separation distance between two adjacent pools are discussed.
Gastrennung mit Druckwechsel‐Adsorptionsanlagen
Authors: Riquarts Hans‐P. , Leitgeb Paul
Published: December 2004

Gas separation in pressure swing adsorption plant. In recent years gas separation in pressure swing adsorption plant has acquired considerable significance as an industrially implemented process. This is particularly true of plant for isolation of pure hydrogen from gas mixtures of various origins. Starting from the underlying principles, this contribution considers the various types of plant for hydrogen isolation, for obtaining carbon monoxide, for recovery of ethylene, for separation of oxygen or nitrogen from the air, and for ozone isolation.
Sicherheitstechnische Maßnahmen bei der thermischen Abluftreinigung
Authors: Hüning Werner
Published: December 2004

Safety measures in thermal waste air purification units. Safety problems may arise in thermal waste air purification units from the occasional explosive nature of the exhaust gases, which may cause a flashback into the production plant. This must be avoided by the installation of safety devices that arrest a flashback. The number of such safety devices is determined by the probability of formation of explosive waste air, according to the zone classification of the explosion‐protection guide. The principal explosion arrestor devices installed between combustion chamber and production plant are liquid submersion systems, detonation barriers, and dynamic flashback‐free inlets into the combustion chamber, all of which must be operated under instrumental surveillance. This report presents a state‐of‐the‐art summary of all suitable procedures and safety devices permitting safe design of systems for thermal air cleaning problems encountered in practice.
Reaktivextraktion
Authors: Schügerl Karl , Hänsel Rolf , Schlichting Eberhard , Halwachs Werner
Published: December 2004

Reactive extraction. A brief survey of reactive extraction and its classification is followed by an account of the reactive extraction of organic solutes. As an example, the reactive extraction of salicylic acid with a secondary amine and NaOH is discussed. Equilibrium constants, overall mass transfer coefficients evaluated in stirred cells and on fixed, freely suspended and pulsated droplets, as well as mass transfer coefficients for the particular phases are investigated. The influence of droplet volume, solute concentration, pH value, and the fluid‐dynamic state of the droplet on the overall and fractional mass transfer coefficients are discussed and compared with various mass transfer models.
Aseptisches Verpacken von Lebensmitteln – Grundlagen und Stand der Technik
Authors: Reuter Helmut
Published: December 2004

Aseptic packaging of foods – fundamentals and state of the art. During the last two decades, a highly successful development has taken place in this area and aseptic packaging is today considered a normal component of technology in many areas of food industry. Aseptic packaging of food can be divided into two main areas of application: 1. Packaging of presterilized and sterile products. 2. Packaging of unsterilized products to avoid the external contamination. In most case, destruction of the microorganisms and spores attached to the surface by a lethal factor obeys the general logarithmic time law. For aseptic packaging of a given product, it is necessary to coordinate 4 factors, viz. the packaging material, the sterilization process for the packaging material surface, the packaging machine itself, and the operating environment of the machine: among these factors, the sterilization process is of greatest importance.
Sicherheitstechnische Aspekte der Prozeßleittechnik
Authors: König Jörg
Published: December 2004

Safety aspects of process control. Safety aspects and safety strategies are becoming increasingly important for modern process control of chemical plants. With respect to configuration, installation, and maintenance, a classification of process control equipment according to the safety relevance turns out to be advantageous. Technical and especially organizational measures have to be adopted to ensure a high degree of safety. Beyond safety requirements in conventional process control engineering the increased implementation of modern control systems introduces new problems. Their information processing power, however, opens vast new opportunities, which are just beginning to be exploited.
Wärme‐Integration und Prozeßoptimierung
Authors: Linnhoff Bodo , Lenz Walter
Published: December 2004

Thermal integration and process optimization. The Pinch method for optimization of thermal integration of chemical plant has been widely accepted in recent years. Serving initially only as an aid in the design of energetically optimized heat exchanger networks, the method was developed in the course of time with regard to the following questions: optimization of heating and cooling systems; simultaneous optimization of energy and investment costs; operability, start‐up and shut‐down behaviour; inclusion of heat engines; optimization of old plant; and process optimization. The fundamentals of the Pinch method are summarized and further developments concerning development of the method for simultaneous optimization of energy and capital costs are presented. Optimization of the BASF butadiene process and the mutual interaction of process and energy system are then presented as practical applications.
Neuere technische Verfahren in der Kohlechemie
Authors: Collin Gerd
Published: December 2004

New technical processes in coal chemistry. The most important commercial basic processes of primary coal conversion are carbonisation, gasification, and hydrogenation. Some 450 mio t/a of coal are converted by coking in horizontal slot type ovens to 350 mio t/a of metallurgical coke for the reduction of iron ore in blast furnaces, coke oven gas, and some 20 mio t/a of coke oven benzole and coal tar as raw material for aromatics. The coke ovens are being developed to high‐capacity coking reactors. New second generation processes for the gasification of coal and lignite have advanced to an industrial scale. A vapor‐phase hydrocracking refining step has been integrated within the further developed process for the catalytic liquid‐phase hydrogenation of coal. Plasma pyrolysis of high‐volatile bituminous coal investigated on a semi‐industrial scale yields acetylene. Pressure hydropyrolysis of coal currently being tested on a pilot plant scale generates high‐aromatic liquid products. New processes for the upgrading of such liquids have been developed above all for aromatics from coal tar, e. g. for the production of naphthalene derivatives, and the conversion of polycyclic aromatic hydrocarbons into the technical carbon products carbon black, electrographite, carbon electrodes, and carbon fibres.
Zur Auswahl wirtschaftlicher Wärmeträger
Authors: Kilger Hans‐Joachim
Published: December 2004

Heat transfer media: the economical choice. The products currently marketed as technical heat transfer media can be classified according to their physical and chemical properties or to the temperature range of their applications. Below 300°C, mineral oils dominate the scene; beyond that range, increasing attention is paid to synthetic media, as novel products with even better performance at high temperatures are being developed. This paper deals with selecting heat transfer media with respect to their characteristics, working life, and the technical conditions under which they are put to use. Additionally, they are evaluated from an economical point of view. Computer‐aided simulation of any kind of heat transfer system in liquid phase is shown to permit calculation of operating expenses for any kind of heat transfer medium. The variety of physical characteristics of these media may result in remarkable differences concerning transfer costs. However, the initial costs and working life turn out to have the greatest influence. Therefore detailed analysis remains indispensable to establish which medium will be best suited to the purpose.
Kinetik und Reaktionstechnik der anaeroben Abwasserreinigung
Authors: Wiesmann Udo
Published: December 2004

Kinetics and reaction engineering of anaerobic sewage treatment. In numerous papers the reaction rate of acetic acid metabolism by methanogenic bacteria, which is frequently suspected as the slowest step in anaerobic digestion, is described by Monod kinetics using total acetic acid concentration as the substrate for catabolism. However, in some papers the authors try to include the influence of pH by using only the un‐ionized acetic acid as the substrate in a Haldane‐kinetic term taking substrate inhibition into account. From this viewpoint, some conclusions regarding reaction engineering aspects of anaerobic waste water treatment are drawn and simple models for the conventional and for the contact process are discussed. The advantage of using support materials for anaerobic bacteria is shown. The space loading can be increased in a two step cascade of fixed bed reactors with external loops for water recycling, with the system being filled with synthetic foam particles as support.
Grenzflächen in der Medizin
Authors: Zembrod Alfred
Published: December 2004

Interfaces in medicine. Some 6 × 1013 individual cells and a variety of differential structures make human organism a highly complex interfacial system. Interfaces play a predominant role in almost all areas of medicine. A number of topical developments which have led to important advances in medical research and practice are selected from the wealth of known phenomena.
Multifunktionale Reaktoren für die heterogene Katalyse
Authors: Agar David W. , Ruppel Wilhelm
Published: December 2004

Multifunctional reactors for heterogeneous catalysis. Consequential exploitation of heat and mass transfer processes in heterogeneous catalysis provides numerous possibilities for reaction engineering. This paper presents a classification covering conventional and new reactor configurations and thus supporting development of optimum reaction engineering for any given case. The classification of catalytic reactors with regard to heat and mass transfer is demonstrated for eight examples taken from the heavy chemicals area. The extended reactor model proves to be a useful framework for reactor design and shows an unequivocal analogy between configurations with corresponding heat and mass transfer processes. The systematic approach indicates possible new solutions for reaction engineering problems.
Instrumentierungsmöglichkeiten an Rundlauftablettenpressen
Authors: Schmidt Peter C.
Published: December 2004

Instrumentation of rotary tableting machines. Instrumentation of rotary tableting machines has two main purposes: to control the tableting process during production and to investigate the compression behaviour of substances. While the former is routinely implemented today, the compression process itself is still under investigation. Measurements are carried out to record compression‐, ejection‐, residual‐, die‐wall‐, and adhesion forces. In addition, displacement of punches is registered. Strain gauges are commonly used for force measurements. For more precise investigations, piezoelectric load washers are installed. Displacement measurements, which are seldom performed on rotary tableting machines, are carried out with inductive displacement transducers. This paper describes the present state of the art. The problems of routine compression force control in tablet production have now been solved. In contrast, a general description of the powdercompression process is not possible in detail. New methods for data collection from rotary tableting machines are described, enabling the pharmacist to reach a better understanding of the compression process.
Einfluß von Additiven und Verunreinigungen auf Kristallisationsprozesse
Authors: Van Der Leeden Mieke , Rosmalen Gerda Van , Vreugd Kees De , Witkamp Geertjan
Published: December 2004

Influence of additives and contaminants on crystallisation processes. The presence of additives and contaminants in a crystallising solution can have a considerable influence on the crystallisation properties of the products, such as nucleation and growth kinetics, agglomeration or dispersion of the crystals, and the incorporation of foreign ions into the crystal lattice. These influences are caused by various mechanisms, depending upon the type of additive or contaminant. Tailor‐made and multifunctional additives are distinguished. Trace amounts of metal ions can also modify the kinetics of crystallisation. The metal ions can be incorporated to a greater or lesser extent in the crystal, depending upon thermodynamic and kinetic factors.
Einsatz von Cross‐flow‐Techniken in der Bioverfahrenstechnik
Authors: Faust Tillmann , Kopf Michael H.
Published: December 2004

Use of cross‐flow techniques in biotechnology.This progress report summarises experience and results gained during the development and optimisation of various micro‐ and ultrafiltration process. The major emphasis lies on the calculation of data which precede actual separation experiments and which define the separation or work‐up problem and the product system involved. To this end the author presents a checklist covering the following areas: definition of the problem at hand, characterisation of the product system and demands placed on membrane plant and membranes. The second area of emphasis is the concept of a flexible membrane test plant. With the aid of this plant, all the data necessary for design and optimisation of a membrane process can be worked out during the laboratory experimentation phase. The principal process engineering tools available for optimisation of the specific filtration performance and maximisation of the product yield are considered. The report considers both the effects and the theoretical fundamentals of techniques for maintaining steady flow of filtrate and for avoiding nonspecific adsorption.