Servizio Comunitario di Informazione in materia di Ricerca e Sviluppo - CORDIS

Olfactory nuisances in cold steel shops and preventive measures and control techniques: Pilot-scale feasability

Tests, on a pilot scale, were carried out with respect to using catalytic oxidation as a method of controlling organic solvent emissions from coil-coating works. The method is an alternative to the existing thermal incineration process. The tests were carried out on two types of pilot installation of similar capacity, one on a synthetic effluent in the laboratory, the other on a continuously operating industrial site. The individual catalytic oxidation study was carried out on 21 volatile organic compounds, the laboratory catalytic oxidation study on three binary mixtures. The laboratory-phase study showed that all the tested volatile organic compounds (VOC) could be converted into carbon dioxide and water with efficiency rates of the order of 99%. Two catalytic converters were selected on the basis of their performance and durability. One was a platinum/palladium model on ceramic monolith support, the other a copper/manganese system. Both of them lasted long enough to be able to operate for a year on a coil-coating line without any special maintenance. Regeneration tests were carried out on the first catalytic converter, which subsequently regained its initial level of activity.

It was concluded that careful selection of catalytic converter can gives an efficient performance in terms of reducing VOC emissions over a one-year period, which is the interval between maintenance operations. At the end of this period the catalytic converter can be cleaned to remove toxic compounds and regain its original level of activity. Compared with the conventional process of thermal incineration, it presents comparable levels of efficiency in reducing effluents, in terms of both olfactory and chemical aspects, and minimizes both oxides of nitrogen production and energy consumption. However, the poisoning of catalytic converters and resulting decline in activity remain a significant problem requiring further study.