| 摘要 |
A process for the fractionation of a porous or fluid-perme-able hydrocarbonaceous solid, such as coal, containing an admixture of mineral matter and hydrocarbonaceous matter, into a separate mineral enriched fraction and a separate hydrocarbonaceous enriched fraction is disclosed. In this process, the hydrocarbon aceous solid is comminuted to convert the hydrocarbonaceous matter in the coal into discrete particles having a mean volumetric diameter of less than about 5 microns without substantially altering the size of the mineral matter originally present in the coal. As a result of this comminution, the hydrocarbonaceous particles can be fractionated from the mineral particles to provide a hydrocarbon fraction having a lesser concentra tion of minerals than in the original uncomminuted material and a mineral fraction having a higher concentration of minerals than in the original uncomminuted material. A preferred method for comminuting the porous or fluid-perm-eable hydrocarbonaceous solid, i.e. coal, is to first form a slurry of coal and a fluid such as water or methanol. This slurry is then heated and pressurized to temperatures and pressures in excess of the critical temperature and pressure of the fluid. The resultant supercritically heated and pressurized slurry is then passed to an expansion zone maintained at a lower pressure, preferably about ambient pressure, to effect comminution or shattering of the solid by the rapid expansion or explosion of the fluid forced into the coal during the heating and pressurization of the slurry. The supercritical conditions employed produce a shattered product comprising a mixture of discrete comminuted hydrocarbonaceous particles having a volumetric mean particle size equivalent to less than about 5 microns in diameter and discrete inorganic and mineral particles having a mean particle size substantially unchanged from that in the original solid. This mineral fraction, in turn, is then fractionated from the hydrocarbonaceous fraction. The product hydrocarbonaceous fraction has a lower density, greater solvent solubility and different reactivity to oxygen than does the feed solid. This hydrocarbonaceous fraction also includes a subfraction of particles having a mean particle size, by volume distribution, equivalent to less than about 2 microns in diameter which contain substantially no sulfur compounds. |
