ISSN:0009-286X    

DOI:10.1002/cite.330510602

出版商:WILEY‐VCH Verlag    

年代:1979

数据来源: WILEY

摘要:

AbstractThe oxitron system: a new biological sewage treatment process for reducing BOD5and for nitrification and denitrification. In the oxitron process, the waste water passes through a fluidized sand bed. As in the case of droplets, a stable biological slime is formed on the sand particles. The particular efficacy of the process can be explained in terms of the high specific surface, of the order of more than 3000 m2per m3reactor volume. This leads to a particularly effective use of available space. The high content of biomass makes the process largely insensitive to fluctuations in feed rates and toxic effects. The oxitron process is used as a biological purification stage for reducing BOD5or as the third purification stage for nitrification and denitrification. The reactor can be operated at particularly high solids concentrations (ca. 20 g/l). The correspondingly high oxygen consumption of this process requires the use of pure oxygen in the aerobic step; over 90% of the oxygen supply is utilized. The special advantages of the oxitron process are: (1) 30% lower capital costs than for conventional processes (operating costs are comparable); (2) space requirements are some 80% lower than for the best conventional technology presently available, facilitating expansion; (3) the mode of operation is extremely simple and is not subject to interference by blockages, etc. Design data and results for large scale test plant are reported.

ISSN:0009-286X    

DOI:10.1002/cite.330510603

出版商:WILEY‐VCH Verlag    

年代:1979

数据来源: WILEY

摘要:

AbstractOrganic and inorganic ion exchangers as catalysts for the heterogeneous alkylation of aromatics. Ion exchangers has advantages over low molecular for use in industrial alkylation reactions. The reactivity and selectivity behaviour of the polymeric catalysts were found to be markedly influenced by the structure of the polymeric matrix as well as the type and number of the functional groups. In this connection many similarities between inorganic ion exchangers (zeolites) and organic ion exchange resins were detected.

ISSN:0009-286X    

DOI:10.1002/cite.330510604

出版商:WILEY‐VCH Verlag    

年代:1979

数据来源: WILEY

摘要:

AbstractTechniques for determining the properties of bubbles in bubble columns. Three different methods for the determination of bubble size parameters namely (i) flash‐photography followed by image analysis, (ii) use of a conductivity probe with two electrodes and electronic processing of the signals, and (iii) the electro‐optical probe with the same signal processing as the conductivity probe are compared and contrasted from the viewpoint of their optimal use, their accuracy, and their scope of applicat

ISSN:0009-286X    

DOI:10.1002/cite.330510605

出版商:WILEY‐VCH Verlag    

年代:1979

数据来源: WILEY

摘要:

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 SO2emission will have decreased by 80% by 1980; the dilution of the SO2emission through use of high stacks will lead to maximum SO2levels of 2 μg/m3in case of modern power plants; all these are low values compared with the upper limits of 140 μg/m3permitted 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 ind

ISSN:0009-286X    

DOI:10.1002/cite.330510606

出版商:WILEY‐VCH Verlag    

年代:1979

数据来源: WILEY

摘要:

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 highe

ISSN:0009-286X    

DOI:10.1002/cite.330510607

出版商:WILEY‐VCH Verlag    

年代:1979

数据来源: WILEY

摘要:

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 circumst

ISSN:0009-286X    

DOI:10.1002/cite.330510608

出版商:WILEY‐VCH Verlag    

年代:1979

数据来源: WILEY

摘要:

AbstractUse of mathematical simulation and miniplant techniques in process development. An integrated study of synthesis and workup or of entire processes is often required in the development of chemical processes. This leads to a large number of possible solutions, of which the most economic one must be selected. This variety can only be mastered at reasonable expense with the aid of present‐day techniques. Examples are presented to show how just a few economic possibilities can be selected and optimized from the plethora of alternatives in simulation calculations based on just a few properties of the materials involved. Economics is the basis of all evaluation. Use of miniplants is considered in the second part of the article, and costs and time‐expenditure are compared with those for industrial pilot plants. Planning and evaluation of experiments raise the effectiveness of this empirical work. Problems of scale‐up are considered, and the advantages of physico‐chemically sound scale‐up models are dem

ISSN:0009-286X    

DOI:10.1002/cite.330510609

出版商:WILEY‐VCH Verlag    

年代:1979

数据来源: WILEY

摘要:

AbstractProduction of glass fibres for optical communications. Optical communications requires lightguide glass fibres with low absorption and scattering losses. A brief description of the principal criteria of light conduction in these fibres is followed by an account of present‐day methods of producing highly pure glasses and fibres. These techniques yield fibres of several kilometers in length with a light attention of about 1 dB/k

ISSN:0009-286X    

DOI:10.1002/cite.330510610

出版商:WILEY‐VCH Verlag    

年代:1979

数据来源: WILEY

ISSN:0009-286X    

DOI:10.1002/cite.330510611

出版商:WILEY‐VCH Verlag    

年代:1979

数据来源: WILEY