| 摘要 |
A multiple hearth apparatus for the thermal treatment of organic carbonaceous materials under controlled pressure and temperature comprises a pressure vessel containing a plurality of superimposed annular hearths 82 which are each formed with a foraminous upper surface disposed in communication with a plenum Chamber 104 for injecting a heated fluid into heat exchange contact with the feed material disposed thereon. The injected heating fluid or gas in further combination with the volatile gases evolved during the thermal restructuring reaction pass countercurrently relative to the travel of the feed material to effect a preheating thereof to a moderate temperature in a preheating zone of the apparatus. Preferably, at least a portion of the product gases withdrawn via outlet 28 are treated to remove condensible portions thereof and are reheated and pressurized for recycle to the plenum chambers. In operation, the apparatus is adapted to operate at temperatures ranging from about 200 DEG F up to about 1200 DEG F at pressures generally ranging from about 300 up to about 3000 psig. Resident times of as little as one minute up to about 1 hour can be employed which will vary depending upon the type of feed material and the desired upgraded solid product. The preheating zone may comprise annular hearths 64 in the vessel, or a conveyor (145, Fig 5) for feeding material to the vessel. <IMAGE>
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