MORPHOLOGICAL PROPERTIES OF THE FIBERS OF DRY DEFIBRATION METHOD FOR CARDBOARD PRO-DUCTION

Article is devoted to a research of morphological properties of the fibers produced from recovered paper by dry defibration method. Fiber length, roughness, torsion, curvature, fibrillation, fines, etc. properties of the fibers produced by the traditional conventional and dry defibration method are compared. Filler (chalk) losses are estimated by recovered paper preparation in the dry defibration method. The studied morphological properties of fibers and content of chalk define surface (roughness, thickness, whiteness) and mechanical (bursting strength, breaking length) test-liner cardboard indicators with a white surface layer. Determination of morphological properties of recovered paper stock fibers allows recommending a combined method of recovered paper preparation (including dry defibration) for test-liner cardboard manufacturers in our country and in the world. Changes of ash content data before and after dry defibration of fibers determine losses of chalk filler. It is known that content of chalk affects mechanical and surface properties of cardboard. Preliminary results of calculations of energy saving from implementation of dry method, carried out during industrial production, showed that at addition of fibers (25% of total weight of fibers in cardboard) prepared by dry method to the main flow, with preservation of mechanical indices of produced cardboard, up to 50 kWh/t of energy is saved.