Alkalische Batterien für Elektrostraßenfahrzeuge – technische und wirtschaftliche Aspekte

Alkali 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.     

Saubere Luft – technische Möglichkeiten,wirtschaftliche Konsequenzen

Clean air – technical possibilities and economic consequences . Starting from the historical development of measures for maintaining clean air in the course of the industrial revolution, the article outlines advances in dust removal which have been accomplished in close, trusting cooperation between legislature, experts and plant operators. The interactions between mankind, technically modified and natural environment, and atmosphere, which have arisen as a consequence of the growth in population, are described and an attempt is made to assign the principal contaminants in the atmosphere to their causers on a global and a national basis. The relationship between rational use of energy and clean air maintenance becomes clear. Additive and integrated air purification procedures are explained with the aid of environmental protection measures adopted in coal-fired power plant and the costs of excessively low emission level demands pointed out. Examples of gas purification plant in the cellulose industry and the printing trade illustrate the possibilities offered by recycling.     

Sauberes Wasser – technische Möglichkeiten,wirtschaftliche Konsequenzen

Clean water – technical possibilities and economic consequences . Water pollution by industrial effluent is becoming more and more of a political warcry which creates a fear of technology – precisely that technology which is largely responsible for the present quality of life. It has so far gone largely unrecognized by the public that industry and municipal authorities have accomplished a great amount in the area of waste water purification. The versatile techniques developed in recent years are summarized, and biological purification is treated in somewhat greater detail. Annual investment in waste water treatment runs at several thousand million DM, and represent a considerable financial burden on industry and municipal authorities. The thesis that economic considerations should play no role in environmental protection is not acceptable in that unqualified form, and would mean that German industry would no longer be competitive in an international arena. Ecological demands cannot be separated from economic considerations. All participants will have to make some compromises on our way to our desired goal of a flourishing economy in an almost intact environment.     

Schmelzkristallisation – theoretische Voraussetzungen und technische Grenzen

Melt crystallization – Theoretical presumptions and technical limitations. The fundamentals of the design of melt crystallization processes on cooled surfaces are presented. Determination of the energy requirement is the essential point. During each freezing step a multiple of the heat of solidification must be removed and must be re-introduced during the subsequent melting step. Consequently, discontinuous processes of this nature can only compete with other thermal separation techniques – in which a continuous countercurrent operation can be realised – if the plant is well designed and the process is precisely controlled.     

Technische und wirtschaftliche Überlegungen zur Elektrotraktion – VW-Elektro-Transporter

Technical 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.     

Industrielle Kristallisation – Moderne großtechnische Anlagen und Fallstudien

Industrial crystallization – Modern industrial plants and case studies . In the field of mass crystallization a number of advanced plant designs have been implemented in the past decade, and are exemplified in the crystallization of adipic acid and common salt, and in evaporation of aluminate liquor which is susceptible to encrustation. Assessment criteria are, inter alia, product qualities such as the purity achieved and the crystal size distribution, and operation parameters such as the duration of process flow and control behaviour. The significant increase in quality is largely attributable to the crystallizers, which have been optimized above all with regard to the crystal-size distribution and the duration of product flow.     

Wärmeinduzierte Vorbehandlung lignocellulosehaltiger Biomassen – Prozesse,Verfahren und deren Einordnung

In the following, different techniques for a heat‐induced pretreatment of lignocellulosic biomass for the production of solid fuels are described. Thereby, also changes at the molecular level of the biomass are discussed. The discussed techniques (torrefaction, hydrothermal carbonization, vapothermal carbonization, and autoclaving) proceed in a temperature range up to 300 °C. Finally, a classification of the different techniques takes place to evaluate the specific advantages and disadvantages.     

Optimierungspotenzial von Wäschen zur Biogasaufbereitung. Teil 1 – Physikalische Wäschen

The number of biogas injection plants is increasing. In Germany, the requirements for biogas injection are specified by DVGW G 260 and G 262. The most applied biogas upgrading technologies are the pressure swing adsorption and physical as well as chemical scrubbers. However, these technologies are usually not adapted to the particular injection parameters of a specific location. In this work the influences of pressure, temperature and further parameters are shown for the water and the Genosorb scrubber. For the simulations the software Aspen Plus was applied, and measurements are used for verification.     

Katalysatoruntersuchungen an einer Technikumsanlage für Biomasse‐Kleinfeuerungen

In addition to the reduction of particulate matter, a catalytic supported emission reduction in small scale biomass combustion systems can also enable a conversion of toxic organic components into carbon dioxide and water. For catalyst investigations under practical conditions a special test facility was designed. The results show that products of incomplete combustion like carbon monoxide from stoves can be reduced by catalytic processes. Further developments and studies are necessary to achieve the targeted emission limits.