| 摘要 |
<p>It is possible to reduce the time required for debarking trunks by friction, for example for dry debarking in a drum for debarking trunks intended for conversion into wood pulp, by means of the prior processing (treatment) of the trunks. During combustion of the bark which has been removed, the latter must be as dry as possible. According to the present invention, the pretreatment, in particular of trunks which are difficult to debark, is improved in such a way that adhesion of the bark to the wood is greatly reduced without it being necessary to supply water to the trunks. This is achieved in that rigid beaters 9, which are joined in an articulated manner to a shaft 13 of a driven rotor which extends essentially transversely to the longitudinal direction of the trunks, are made to collide against the trunks 5 over an area and with an impact force which are sufficient to weaken the union between the bark and the wood through fatigue and/or transportation of moisture, induced mechanically, from the inner bark to a meristem layer which is located between the bark and the wood and which joins them together. The arrangement for pretreatment preferably includes at least one pair of rotors which has rotors 7, one above and one below, of a working width such that it is possible to process simultaneously a plurality of trunks placed side by side. (Fig. 1)</p> |
