| 摘要 |
<p>The present invention relates to a method and apparatus for treating fiber suspension, for example, sorting or grading. The method and apparatus in accordance with the invention is especially suitable for the treatment of fiber suspensions in the pulp and paper industry. The most serious defect in the known apparatuses is that the relative amount of the reject, in other words the material which is unqualified for the finished product, adjacent to the screen surface rises directly in proportion to the distance from the initial or front end of the screen surface since acceptable fraction is discharged through the screen surface, but the reject is discharged only after it has traversed the whole length of the screen surface. In the arrangement in accordance with the present invention the treatment space for the suspension is divided into several zones (21, 22, 23), from each of which the reject accumulated in them is discharged to its own treatment zone (24). New unsorted suspension is also fed in said zones so that, for example, in a screen apparatus of a conventional size there may be three separate zones treating unsorted pulp and one zone treating reject.</p> |
