| 摘要 |
A unitary heating chamber includes two heating zones for successively removing volatile combustible matter from dried coal particles so that the resultant calcined char has less than about 7% by weight volatile combustible matter and is suitable as a raw material for producing formcoke. In the first zone (carbonizing zone) (32) heat-carrying solids are introduced into a rotating retort (38) with coal particles to heat the coal particles to a temperature in the order of about 425 DEG C to 540 DEG C and produce a carbonized char containing about 10% to 20% by weight of combustible volatile matter. The resultant carbonized char is fed onto a trommel (40), and only the carbonized char passes through the trommel into a fluid bed calcining zone (34). The fluid bed calcining zone (34) is maintained by upwardly directed jets (50) of an oxygen-containing gas and steam. The temperature of the fluid bed calcining zone (34) is in the vicinity of about 650 DEG C to 880 DEG C whereby the combustible volatile matter content of the calcined char is reduced to about 7% by weight or less, as it is withdrawn from the fluid bed calcining zone (34). The heat-carrying solids which supply heat to the carbonizing zone roll over the trommel (40), and are thereby separated into a zone (46) so that they may be reheated and used again. The combustible volatile matter generated in the two heating zones are mixed and drawn off through a common outlet (54). |
