| 摘要 |
<p>PURPOSE:To prevent cracking of a green pellet by kneading coal ash rich in CaO with hot water at a specified temp., then granulating and sintering the kneaded material. CONSTITUTION:The coal ash discharged from a fluidized-bed boiler, etc., clay and hot water at >=50 deg.C are kneaded by a kneader 3, the kneaded material is granulated by a pan granulator 4 to obtain a green pellet. The pellet is charged into a feed hopper 5, supplied on the grate 6' of a calcining furnace 6 isolated from the atmosphere and dried with hot air, and then the surface layer of the pellet is ignited by a igniter 9 and heated to about 1150 deg.C. The gas flow rate at the inlet of the furnace is controlled to about 1400Nm<3>/h and the O2 concn. at the inlet to about 13wt.%, the pellet is sintered for about 15min, and an artificial lightweight aggregate is produced.</p> |
