Response to parameter variation of a one-inch diameter hydrocyclone for pyritic sulfur removal

An investigation of the literature showed that as the diameter of a hydrocyclone was decreased, smaller particles could be effectively separated on the basis of specific gravity. Consequently, a laboratory scale study was conducted to determine the possibility of removing pyritic sulfur from fine coal using a 1.0" diameter hydrocyclone.

A 1.0" diameter hydrocyclone was constructed from stainless steel. The hydrocyclone was fabricated with easily interchangable parts that permitted rapid variations in the inlet diameter, apex discharge diameter, vortex finder diameter, vortex finder position, and cone angle. The feed pressure to the hydrocyclone could also be varied. A recirculating system was used.

Synthetic material was used in place of actual coal during this investigation. The synthetic material, made from casting resin and barium sulfate, duplicated the coal with respect to particle size, shape, and specific gravity distribution. The synthetic coal had the advantage of not degrading during the course of the experiment.

Three coals were simulated for the purposes of this experiment. Pocahontas 113 coal served as the "light" coal, the Hagy seam was selected as the "medium" coal, and coal from the Cortes area of New Mexico was chosen as the "heavy" coal. By optimizing the 1.0" diameter hydrocyc1one for these three coals, it would be possible to extend the results of the investigation to any coal. The results of the investigation showed that the 1.0" diameter hydrocyclone was an effective device for removing pyritic sulfur from 65 x 200 mesh coal. The results for the minus 200 mesh size fraction were not good. A smaller diameter hydrocyclone would be necessary in order to effectively process the minus 200 mesh size fraction.