| 摘要 |
PURPOSE:To produce the title slurry which has excellent storage stability free from precipitation and coagulation, by incorporating an anionic additive and a nonionic additive at respective pulverization steps meeting the characteristics thereof. CONSTITUTION:Coals 1 and water 2, together with an additive 4, are fed into a mill 7 by means of a screw feeder 6. In the mill, the coals are pulverized, thereby obtaining pulverized coals. The additive adheres to the surface of the pulverized coal particles, thereby contributing to the prevention of coagulation of pulverized coal particles and increasing the coal concn. The interior of the mill 7 is partitioned by means of a diaphragm 8 into a plurality of chambers, and an optimum combination of ball diameter, ball mixing and ball packing ratio is selected. As an additive 4 to be fed into the inlet side of the mill, a nonionic additive which is inferior in temp. resistance but superior in thickening capability is used since the interior of the mill is in a low-temp. region. On the other hand, as an additive 12 to be fed into the outlet side of the mill, an anionic additive having excellent temp. resistance, durability and stability is used since the interior of the mill is in a high temp. region. By the above method, a coal-water slurry which has improved storage stability free from precipitation and coagulation of pulverized coals, as compared with that of the conventional slurry obtd. by using only a single type of anionic additive, is produced.
|
