Surface characteristics of coal-oil agglomerates in the floc regime

Reduction of the amount of wetting phase used in the oil agglomeration process for advanced coal cleaning and utilization technologies is important to the economics of the process. This paper reports on the agglomerate surface properties and on the size enlargement characteristics and possible mechaisms of the process taking place when a few percentages of oil are used in oil agglomeration and floc-type coal agglorerates are formed. Since this product exists not as dense agglomerates but only as small aggregates of a few particles, the adhesion technique was used to determine the surface properties of agglomerates made from a high-purity coal. The surface properties closely matched those of the oil at agglomerate oil levels above 2% by weight. Particle size measurements by laser diffraction were then correlated to the surface properties as a function of the oil level and of agglomerate particle packing.NRC publication: Ye