Sulphur reduction studies in UK coals

This paper describes investigations carried out as part of a project to determine the potential for sulphur reduction in UK coals and is concerned, in particular, with the effect of particle size reduction on the liberation of sulphur. This work required the development of a modified float/sink procedure to enable the density characterization of coals down to ultrafine sizes. The liberation data produced were used to determine the theoretical reductions in sulphur emissions that could be achieved for these coals using density based separation methods. Finally, process simulation models were applied to the data in order to predict the results that could be achieved using conventional techniques applied in commercial practice. The main conclusion from this work was that there is considerable potential, in theory, for further sulphur reduction in UK coals by comminuting them to liberate pyrite. However, to make any significant reduction in practice will require the development and application of more advanced coal preparation techniques, particularly for the treatment of fine coal.