The Use of the Pot Furnace for the Prediction of Stoker Performance

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CURRENT AND FUTURE ACTIVITIES As was mentioned in the section on Coal Evaluation our re-built pot furnace test facility has already resumed its activity in that function. The significant improvement is that over bed gases can be subjected to continuous and virtually instant analysis. A knowledge of oxygen level allows us to optimise the undergrate air, in particular the distribution pattern along the length of a travelling grate stoker with much greater ease than hitherto. It is believed that this aspect will become increasingly important since some of the fuels now coming on to the world market are of lower quality than would hitherto have been considered for stoker application. An equally important aspect of our immediate attention is that of pollutant emission. The time separation of the pot furnace technique and the on-line gas analysis facility provide an ideal opportunity to investigate from which parts of the bed pollutants are emitted and the rates of such emission. The pollutants of major significance in this respect are the nitrogen and sulphur oxides. From there we can proceed to investigate whether the emissions can be reduced or controlled by techniques of combustion modification. It is hoped that the knowledge of where to attack the problem of emission will go some way to providing at least part of the answer tc the aspect which Ref. 1 saw as an area of insufficient information availability. 24-19