| 摘要 |
An improved method is described for treating sewage sludge. The sludge in the form of a slurry is continuously distributed onto preheated aggregate pieces which are continuously fed into a lower region of a rotating contactor drum. A portion of the slurry substantially instantaneously adheres to the heated aggregate and the non-adhering slurry passes through perforations in the drum for recycle. The aggregate with adhering sludge is carried upwardly by means of baffles in the drum and is dumped into a collector trough in an upper region of the drum. This coated aggregate is subjected to further heating as it travels down an inclined path to dry the coating into a hard encrustation and enters a tumbler drum which breaks the sludge coating away from the aggregate and pulverizes the sludge into a dust or powder. This dust is collected as product and the decoated aggregate is recycled.
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