| 摘要 |
A coal slurry containing 10-60% solids by weight is optionally first coarsely ground to about 20-80 mesh. Contaminant matter released thereby, may be separated by conventional means such as froth flotation which would eliminate a large proportion of the ash which is energy consuming as well as abrasive in nature. The "clean slurry" would now have water added back and would be further ground to about 100-300 mesh particle size and would then be cavitated by sonic energy making the particle size even smaller and freeing any remaining contaminants including iron pyrites and ash. To this, a mixture of oil is added and the coal, oil mixture is then sonified during which process spherical agglomeration of the coal and oil occurs. 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 are also discharged with the water. The spherical agglomerates are mixed with a balance of oil to about 0.6 times the weight of the coal to produce a stable thixatropic fuel with excellent pipe travel characteristics due to a migration of a thin film of water to the boundry layer between the bore of the pipe and the fuel. The process including the sonification steps is also useful generally in the separation of solids by agglomeration. |
