ABSTRACT

As column flotation is increasingly accepted by the coal industry, more ultrafine coal waste is being recovered. However, its dewatering becomes a challenge since the commonly used vacuum filtration can not successfully reduce moisture to an acceptable level. Asphalt emulsion is found to be promising in reducing cake moisture by agglomerating ultrafine coal particles. Laboratory experiments of vacuum filtration dewatering of ultrafine coal slurry have shown that cake moisture can be lowered from 35% to 25% with an addition of 1% by weight CCB asphalt emulsion. The asphalt emulsion has been characterized for viscosity, droplet size distribution, and zeta potential. The effects of asphalt emulsion dosage on agglomerate size distribution are also investigated.