Möglichkeiten zur Bodensanierung

Possibilities of soil clean-up. Abandoned hazardous sites are abandoned waste sites or industrial sites which threaten human health, the environment, or other aspects of public safety. The enforcement of clean-up of abandoned hazardous sites lies with the Federal German States. Registration and evaluation programmes are underway. Up to now nearly 50 000 suspected sites are registered in the former States of the Federal Republic of Germany and nearly 28 000 in the new states. Calculations of more than 100 000 suspected sites have been made. Several techniques are available for clean-up which had been funded within the framework of numerous R&D-programmes. The clean-up technologies operating in praxis include thermal treatment, physico-chemical treatment (soil washing and soil venting), and biological treatment. Future trends focus on combined treatment technologies in soil treatment centers.     

Möglichkeiten zur Emissionsminderung in Lackieranlagen

Possibilities to Lower the Emissions of Varnishing Plants Varnishing plants for industrial producer goods partly emit considerable air pollutions (aerosols, gases, vapours, odours) and noise to environment. These emissions have to be reduced by specific measures, to meet the legal requirements. To lower emissions as well primary as secondary measures offer themselves. Primary measures are technical possibilities which cause from the very beginning lower amounts of polluants, e.g. by use of coating systems which are poor in solvent or free of solvent and/or coating procedures with high coating efficiency. Furtheron measures to lower the coating size like work construction favourable to coating and use of qualitatively better coating systems belong to them. All methods to subsequent cleaning of waste air like subsequent combustion, absorption or adsorption are reckoned among secondary measures. The essential emissions of single procedure steps of coating are delt and possibilities to lower the emissions are discussed.     

Möglichkeiten zur Vorausberechnung von Verweilzeitverteilungen

Possible Approaches to the Prediction of Residence Time Distributions Although the experimental determination of residence time distributions is based on a black-box method, the signal shape also permits certain conclusions to be drawn about the internal conditions. However, if it is to provide a sole basis for elucidating process steps in a plant this method is soon overtaxed. A deeper theoretical penetration of the pertinent transport processes opens up the way ahead. However, since residence time distributions are based on mass-oriented considerations, substantial advances in fluid mechanics, where location-based considerations predominate, have not led to improved predictive capability. Yet the computer power now available offers a variety of ways of calculating residence-time distributions for a known flow profile, thus permitting a step in the direction of better predictability of residence time distributions. This article presents utilisable methods and evaluates them with regard to their demands on time and effort and their predictive power. Problems arising in connection with the models are discussed.     

Neue Möglichkeiten zur Energieeinsparung in Soja-Extraktionsanlagen

New Feasibilities for Lowering of the Energy Consumption in Extraction Plants of Soya Bean The fundamental news is a procedure for waste air recycling of the seed dryer for prewarming of the seed before flaking. The steam consumption for a complete soya bean extraction plant (without hull separation) is less than 150 kg per ton of worked soya beans at simultaneous reduction of the total electricity consumption. The fundamental equipment parts for this energy reduction consists in a technically altered toaster-dryer-cooler system, expander and reuse of steam containing waste air of drying and cooling systems.     

Möglichkeiten zur Prozeßintegration bei destillativen Trennverfahren

Possibilities of process integration in distillative separation processes . Distillation is the most important method of separation in the petroleum and chemical industries. About one quarter of the energy consumed in these sectors of industry is for distillation. This underscores the importance of improving distillation processes. Optimisation work on distillation processes has been in progress for a long time. Attention has recently been turned to the treatment of overall separation tasks which can be integrated into chemical engineering processes. To this end, the heuristic rules usually employed in the design of distillative separations have been further developed. Use of expert systems which transform these heuristic rules into separation proposals already appears feasible.