ABSTRACT
A major collaborative research programme has been put together in the UK to address all aspects of slagging in pf-fired furnaces. The programme consists of an integrated package of full-scale plant trials, rig tests, laboratory-scale tests, deposit and particulate characterisation using advanced analytical techniques, and the development of computer models. The main objective is to provide a reliable method for the prediction of slagging, accounting for the interaction of boiler design, operation, and coal composition. The individual elements of the programme are briefly described in this paper. A key element is the full-scale plant trials at Ratcliffe Power Station and the test philosophy and measurement are described in more detail. The planned four trials of 5 days duration each firing coals of variable slagging propensity have been successfully completed. Three trials were on a 500MW boiler that has been retrofitted with low-NOx burners. For comparison, a fourth trial on a boiler with conventional burners was included. The bulk analysis results for the flyash and deposit samples collected during these trials are presented and show consistent, but coal-specific, chemical partitioning, indicative of selective deposition processes having occurred.
