| 摘要 |
<p>The invention relates to a method and a screen for screening two or more pulp mixtures with different roughness. The screen comprises a first screen cylinder (2) and a second screen cylinder (6). A coarse first pulp mixture is fed into the inlet end of the first screen cylinder, and a second, less coarse pulp mixture is supplied to the second screen cylinder. The pulp mixtures are screened by means of a screen surface of the screen cylinders into accept that passes apertures provided in the screen surface and reject that does not pass the apertures. The accept from the second cylinder is conveyed by means of a guide tube (23) provided between the cylinders towards the inlet end of the first cylinder and it is finally mixed with the first pulp mixture. The accept from the first and the second pulp mixture passes the screen surface of the first screen cylinder, whereafter the accept is gathered in a common recovery basin (17). All the reject is conveyed to the discharge end separately inside each cylinder.</p> |
