Rapid prediction of floating and sinking components of raw coal

A model that rapidly predicts the density components of raw coal is described. It is based on a three-grade fast float/sink test. The recent comprehensive monthly floating and sinking data are used for comparison. The predicted data are used to draw washability curves and to provide a rapid evaluation of the effect from heavy medium induced separation. Thirty-one production shifts worth of fast float/sink data and the corresponding quick ash data are used to verify the model. The results show a small error with an arithmetic average of 0.53 and an absolute average error of 1.50. This indicates that this model has high precision. The theoretical yield from the washability curves is 76.47% for the monthly comprehensive data and 81.31% using the model data. This is for a desired cleaned coal ash of 9%. The relative error between these two is 6.33%, which is small and indicates that the predicted data can be used to rapidly evaluate the separation effect of gravity separation equipment.