Recovery of the components of multiple layer materials, for instance recovery of paper, plastic and aluminium foil from beverage packaging materials, has earlier been achieved with the aid of large drum pulpers or traditional pulpers, to which chemicals are normally added. Such large plants incur heavy investment costs, require large construction and installation areas, and consume large amounts of energy, which explains why such plants have not been used more widely.
SE,B,417 623 (Escher Wyss) discloses a method in which particles processed in a disperser are rolled to form small compact grains. The known method requires comprehensive treatment of the material upstream of the disperser and is therefore expensive and highly energy consuming.
SE,B,383 006 (Munksjo) described a method of recovering fibers from waste paper with the aid of a rotatable perforated drum provided with lifting means. The document is not concerned with layer separation of waste material.
USPTO Backgrounds
USPTO Backgrounds