| 摘要 |
Fluid charged with the chips is arranged to pass through the chip column in the entry zone in the chip feed unit at such a speed, before the fluid is drawn off, that the chip column passes through the following impregnating fluid as a counter-stream to the chip column charging. It is structured that the heat capacity flow of the impregnating fluid is at least equal to the flow of heat capacity of the forward-moving chip column. The method allows sufficiently sharply-defined temp. bands and sufficiently large differences in temp. can be provided in the entry, impregnation and breakdown zones in a continuous refining process. This allows an effective impregnation of the finely-ground cellulose material with chemicals before the breakdown reactions start. The fluid temp. for the feed of finely-ground material can be held lower than its b.pt. at normal atmos. pressure.
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