Abstract The law of conversion from pulverized coal into fly ash is discussed and a model is buiit up for determining unburned carbon loss in the fly ash from pulverized coal boilers

This moded can be used to predict the functional relation between unburned carbon loss and pulverized coal fineness. A calculation was made by the author on a pulverized coal boiler in operation. The results show that under operational condition of boiler there is a optimum fineness for burnout of pulverized coal. The method proposed in this paper can be used for directing the boiler operation especially when burning a coal with poor grindalitity

poor burn-out rate or higher ash content.