| 摘要 |
PURPOSE:To decrease the ash-content of coal remarkably, to reduce the cost of cleaning liquid and to improve the stability and handleability of the cleaning liquid, by treating granular or pulverized coal with a cleaning liquid composed of an aqueous solution containing hydrogen fluoride and hexafluorosilicic acid. CONSTITUTION:Coal is crushed to obtain granular or pulverized coal having particle diameter of about 0.1-3mm. The granular or pulverized coal is treated with a cleaning liquid consisting of an aqueous solution containing hydrogen fluoride and hexafluorosilicic acid to dissolve the ash from the coal to the cleaning liquid. The deashed granular or pulverized coal is separated from the cleaning liquid e.g. by filtration and washed with water. The deashing temperature is higher the better and a sufficient deashing can be achieved by the treatment at 80 deg.C for 1-2hr. However, a practical deashing can be carried out even at about 20 deg.C by elongating the treatment time. |
