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The main result of this research work is a concept for low emission operation of a typical industrial slag quenching system with reference to emissions of steam and subsequently gaseous sulphur compounds such as H2S and SO2. Guidelines and process schemes for the implementation and optimised performance of secondary and primary treatments are formulated on the basis of extensive laboratory and industrial trials. The first step of the research work has been the collection and evaluation of data about sulphur compounds emissions and operational conditions at industrial slag granulation plants. A reduction of H2S formation can be obtained by use of chemical reagents supplied to slag or granulation water (primary means), which oxidise the sulphide in the slag to sulphate or which provide oxidising conditions at the slag/water interface. Iron oxide supplied to the slag is expected to be the most economic and effective additive. Other suitable primary means to influence the H2S formation are constructional improvements like modifications of the granulation head in order to intensify the slag/water contact. The release of steam can effectively be reduced by secondary constructional means such as optimisation of gas flow conditions inside the condensation tower and optimisation of the steam condensation by use of a modified condensation system. Further effective secondary means to decrease H2S emissions are gas scrubbing processes. Possible absorbents are aqueous solutions of NaOH or ferric EDTA. Main advantage of ferric EDTA solutions is its ability to be regenerated with air and the discharge of sulphur compounds as elemental sulphur. (Copyright 2003 Stahlinstitut VDEh)