| 摘要 |
1516000 Gasifying carbonaceous material in a rotary kiln ALLIS-CHALMERS CORP 20 Sept 1976 38820/76 Heading C5E Solid carbonaceous material, particularly coal, which exhibits a tendency to agglomerate at a predetermined rate depending on its free swelling index after it attains a first agglomerating temperature and which loses the tendency at a second higher non-agglomerating temperature, is gasified in a rotary kiln by (a) admitting sufficient heat to a tumbling bed of the material in a devolatilizing zone to raise the temperature therein to the second higher non-agglomerating temperature before the agglomerates have been exposed to the first agglomerating temperature for a length of time sufficient for the agglomerates to have grown to a size greater than a predetermined agglomerate size which is determined by the capability of the kiln to allow movement of the material therethrough, (b) admitting steam to the tumbling bed in a gasifying zone of the kiln downstream of the devolatilizing zone to cause gasification of the material of the bed therein and (c) continuing the tumbling of the material to ensure that an agglomerated material which has attained the non-agglomerating temperature will be broken up before the material is discharged from the kiln. A preheating zone may be arranged before the devolatilizing zone, the temperature of the material not attaining the agglomerating temperature until it has reached the devolatilizing zone. It is preferred to use air in the devolatilizing zone to raise the temperature of the material rapidly from 700‹F to 1600‹F. |
