Fast cost-saving more efficient separator which yields high quality pulp

摘要

A process for the extraction of undesirable solid particles from fibre pulp suspension (S) suitable for paper mfr. uses a separator (1) with many openings (4) through which passes the predominant fraction of fibre pulp because of the hydraulic pressure gradient while the predominant fraction of undesirable particles is held back. There are means (5) for keeping the openings clear of solids and the material which has not penetrated flows along the separator. Here, separator openings reduce in at least one dimension as non-penetrating solids flow through. Also claimed for process implementation is a slotted strainer cage having a conical cover formed by bringing slats together at an acute angle so the slots between them narrow as they run axially. Alternatively the cage is cylindrical but the slats widen axially to narrow the slots or are equal in width axially, drawn together in groups at an acute angle and inter-group spaces filled by trapezoidal plates. Also claimed is a cylindrical cage with holes with larger dia. near the entry than they have near the exit.