Abstract: A rotary pulp screening device of the horizontal type is disclosed having a high screening efficiency and high capacity. The screening device provides a streamline flow of pulp and one of its aims is to supply a fairly constant velocity of pulp along the length of the screen thus utilizing its full length.

Abstract: A rotary pulp screening device of the vertical type is disclosed having a high screening efficiency and high capacity. The screen provides a streamline flow of pulpstock, and aims to supply a fairly constant flow of pulp through the screen from top to bottom, thus utilizing the full height of the screen. The screening device includes a cylindrical housing with a vertical cylindrical screen therein, a rotary impeller mounted for rotation within the screen, the impeller having a body whose top is substantially level with the disc ring and bottom is adjacent the lower end of the cylindrical screen, the body having a shape with circular axial cross section from the top to the bottom, whose diameter increases from the top to the bottom thus leaving a larger annular space at the top, and impeller blades radiating from at least a portion of the body of the impeller and extending to within a short distance from the screen for the height of the screen.

Abstract: A discharger mechanism is provided for discharging solids from the bottom of a pile. The discharger comprises a reciprocating stoker rod of a substantially rectangular cross section and plastimeric bearing member engaging the bottom and sides of the rod for vertically supporting and horizontally guiding the rod. A reciprocating device reciprocates the rectangular stoker rod longitudinally beneath the pile. A plurality of stoker cross bars are equispaced apart and rigidly attached at their centers to the rectangular stoker rod. A further bearing member bears against the top of rod to prevent the rod from lifting.

Abstract: A discharger mechanism is provided for discharging solids from the bottom of a pile. The discharger comprises a reciprocating stoker rod having a series of stoker cross bars, affixed thereto, which is supported by bearings within a trough. An arrangement for holding down the rod and for sealing the trough comprises a pair of longitudinally extending metal strips attached to either side of the rod and a pair of seal strips or plates secured to the edges of the trough and extending therefrom into the trough to positions above and adjacent to the upper surfaces of the metal strips.

Abstract: A rotary pulp screening device is disclosed which is less sensitive to variation in pulp flow, pulp consistency and pressure than existing pulp screens. The device is of the vertical pressure type and includes a cylindrical housing having an upper inlet chamber and a lower screening chamber with a disc ring dividing the upper chamber from the lower chamber, an inlet aperture in the upper chamber, a cylindrical screen mounted within the lower chamber, a rotary impeller mounted for rotation about a central vertical axis within the screen, the impeller being approximately in the form of a paraboloid, means for rotating the impeller, impeller blades radiating from the impeller and extending to within a short distance of the screen over the length of the screen, at least two dilution systems for diverting dilution water into different areas of the screen and a pulp discharge outlet from the lower chamber outside the pulp screen.

Abstract: A bark shredder is disclosed for shredding bark and other waste wood products into small pieces. The shredder rotates in either direction unlike existing bark shredders which allows twice the normal operating time between servicing. The shredder has a casing defining a cylindrical working chamber with a top inlet and a bottom symmetrical outlet. A rotor is mounted axially in the chamber and a plurality of fixed shredding elements are attached to the casing in a circle at one level of the chamber intermediate the inlet and outlet, the fixed elements extend radially inwards. The rotor has a plurality of rotating shredding elements pivotally attached thereto and located above but adjacent to the fixed elements. The fixed and rotating elements are shaped to co-operate with each other to shred material in the chamber when the rotor is rotated in either direction.