Betriebsleittechnik – Funktionsumfang und Stand der Systeme

Process Control Engineering – Function and State of the Art of the Systems On considering material flow in a chemical engineering company it is possible to identify associated business processes whose support by appropriate information processing systems will permit efficient control of material flow and material conversion as production goal. Such consideration indicates not only the principal functions of information processing but also the necessary integration of process-oriented information systems such as those relating to formulation, production planning, and operating data processing. Various concepts are currently under discussion for such integration.     

Membranen für Polymerelektrolyt‐Brennstoffzellen

Membranes for Polymer Electrolyte Fuel Cells The polymer electrolyte membrane is the heart of hydrogen fuelled Polymer Electrolyte Fuel Cells (PEFC) and methanol fuelled Direct Methanol Fuel Cells (DMFC). Membranes of sulfonated fluoropolymers are already commercially available. Important goals for research and development are for PEFCs an increased operating temperature without the need for additional humidification and for DMFC the reduction of methanol transport through the membrane. The use of non‐fluorinated polymers aims at a reduction in membrane cost and environmental hazards. Membranes already in industrial product development are considered as well as novel membrane concepts in fundamental research.     

CAD in der Anlagentechnik – Gegenwärtiger Stand,Probleme und Chancen

CAD and plant engineering. State of the art, problems, and prospects . CAD was first used for special tasks, that is for especially sensitive design, e. g. in the aircraft industry, or mass-produced articles, e. g. in the automotive industry. For about one decade, CAD has been used economically in all areas of design. This paper describes the state of the art of CAD use for plant engineering. It may be seen as the termination of a thorough test. Now the time has come to decide on the future use of CAD. Problems encountered are therefore reported. The prospects of CAD are outlined on this basis.     

Adsorptive Behandlung VOC‐haltiger Abluftströme – Stand der Technik

VOC Adsorption Technology – State of the Art This review gives a general overview of the state of the art in VOC adsorption technology. An analysis of 247 plants built between 1986 and 2003 shows that only five combinations of desorption process and adsorber design are widely used in industry. Besides non‐regenerated fixed‐bed‐adsorbers these are PSA‐fixed‐bed‐, TSA‐fixed‐bed‐ (steam), TSA‐fixed‐bed‐ (purge gas) and TSA‐rotating‐disc‐adsorbers. Moving‐bed adsorbers can be found only in specific niches. In the second part of the article advantages as well as disadvantages of each technology are discussed based on typical examples from industry. These properties lead to specific limitations of each technology in industrial applications, which are visualized in a matrix plot.     

Selektive Reduktion von Stickoxiden in Rauchgasen – Stand der Technik und neue Wege

Selective reduction of nitrogen oxides in flue gas–state of the art and trends . The selective reduction of nitrogen oxides by ammonia may be catalyzed by different substances. The suitable choice of the catalyst is determined largely by where the reduction step is placed in the overall process. The technical problems and the required catalyst properties are demonstrated and discussed. A new process, based on a periodically operated reactor, avoids some of the difficulties otherwise encountered.     

Bioreaktoren — derzeitiger Stand und erkennbare Entwicklungen

Bioreactors – State of the art and recognizable future developments. Industrial biotechnological processes, which require monoseptic conditions, are currently performed largely batchwise in stirred tank reactors. A broad-based exploitation of the potential of biotechnology, i.e. both in the production of commodity biologicals/chemicals and in the manufacture of products of the ?new”? biotechnology, requires, for economic and technological reasons, continuous processes and other reactor configurations, which permit increased biomass concentrations by cell retention or immobilization, and integration of work-up operations.     

Abfallbeseitigung auf See — Stand und Tendenzen

Waste disposal at sea – state of the art and developments . The article starts by describing the legal situation governing the disposal of waste at sea and then considers the licensing procedure according to the ?Oslo-London treaty law”?. The Federal German Department of the Environment is also involved in this licensing procedure in that it is responsible for examining the possibilities of disposal on land. The quantities of material for disposal have been considerably reduced in recent years in all areas. The disposal of sewage sludge and of dilute acids (from the production of organic dyes and pigments) in the North Sea has now stopped completely. The amount of waste for disposal from TiO₂ production has been greatly reduced and stepwise cessation is planned by the mid -1980's. The incineration of waste on the high seas has also been restricted and will also be stopped in the long term. The results of ongoing and completed research are reported.