ES8405059A1 - Processes for cleaning minerals and for producing stable suspensions/emulsions,particularly fuels comprising coal,oil,and water - Google Patents

Abstract

A coal slurry is agitated and may be cavitated under pressure by sonic energy so that contaminant matter may be released from the coal and then separated. The clean slurry is then cavitated under pressure by sonic energy making the particle size even smaller and freeing any remaining contaminants including iron pyrites and ash. During sonification of the clean slurry a small amount of oil is added to cause floculation and spherical agglomeration of the coal and oil to occur. The agglomerate and water mixture is screened to separate out most of the water leaving behind about 10-40% water in the coal, during which process the contaminants in the discharged water are also discharged. The spherical agglomerates are mixed with a balance of oil to produce a stable coal, oil, water fuel and is again agitated, preferably sonified, to further reduce the particle size of the coal and to irrigate the coal particulate. Stability of the fuel is enhanced by combining distillate oil and residual oil in the process. In some instances heating the water used in the clean slurry also assures stability. Apparatus for carrying out the process is also disclosed. The processes are applicable to a wide range of mineral slurries to stabilize such suspensions or dispersions.Methods are claimed for producing fuels from coal particles, pref. run of the mine coal, with water and opt. oil. In the first method, a coal-water slurry is vibrated to produce cavitation, to remove impurities from the coal and to reduce the particle size, and the impurities are then mechanically removed and the slurry is partially dewatered. In the second method, the slurry is treated as above and then oil is added to agglomerate the coal the mixture is again partially dewatered and then agitated with further oil to form a stable emulsion. In the third method, the aq. coal slurry is cavitated using sonic energy, with simultaneous addn. of oil. followed by partial dewatering and emulsification with further oil. Also claimed is fuel produced by the third method in which the oil is a mixture of residual oil and distillate oil. lt . The combination of beneficiation and agglomeration gives a high quality fuel product, and the use of sonic (or ultrasonic) energy allows a stable emulsion to be formed with higher solids content and lower oil content. -