Kinetics of agglomerate growth in a continuous coal-oil purification process

Abstract

A continuous coal-oil agglomeration process has been developed in a pilot plant for continuous coal purification prior to coal-water slurry preparation. The kinetics of agglomerate growth has been studied and a model has been adopted for the continuous process. This model is in a good accordance with the model proposed by Rao and Vanangamudi, for bath coal-oil agglomeration conditions. The size distribution of coal particles after agglomeration has been predicted using a characteristic curve, which utilizes the value of the feed top size of coal and the estimation of the mean size d sv (surface-volume) of agglomerates. It becomes also possible to quantify the coal recovery after passing agglomerates over a given sieve-bend. A description of agglomerate characteristics is then possible in terms of relationships giving the agglomerate mean diameter versus other characteristics of coal agglomerates, such as included moisture and rate of ash removal after separation process.