Adhesion of Micron Sized Coal Particles to a Massive Coal Substrate

Abstract

The force of adhesion between 2–5 μm coal particles and a coal substrate was measured using an ultracentrifuge. The repeatability of the data was about ±8 percent. The data indicate that neither the orientation of the substrate surface with respect to its bedding planes nor an initial positive charge of several hundred elementary units significantly affects the force of adhesion. However, the force of adhesion on cleaved substrates is about 40 percent higher than on those which were mechanically polished. The force needed to remove 50 percent of the particles was about 2 millidynes.