摘要 |
<p>Mechanical cellulosic fibrous material pulp (mechanical pulp to produce paper products) having lower freeness, and enhanced light scattering properties, tensile and tear strengths, for a given energy input, is produced by force feeding a refiner (10). Using a progressive compacting plugscrew (12,46,48), cellulosic material (e.g. wood chips) is fed to the refiner inlet (15) at a rate greater than the transporting capacity of the refiner (e.g. about 10-40% greater). The refiner preferably is a low frequency conical refiner with steam removal (22) at the grinding area between the conical refiner elements (18,19). The production rate is regulated by sensing (via 32) the axial force on the refiner rotor and controlling the spacing (21) between the refiner elements (18,19) in response to the sensed axial force. The screw has a compaction ratio of at least 3/1 for wood chips and 6/1 for pulp, and is rotated at about 6-10% the speed of rotation of the refiner rotor.</p> |