Abstract: Pressure type screening apparatus for screening papermakers' stock and method of use is disclosed. Screen (20) has an inlet screening surface (23) and an outlet surface (unlabled). Pressure transducers (not shown) vary the fluid pressure on the inlet surface of the screen (23) from a maximum to a minimum, and also vary the fluid pressure on the outlet surface of the screen (20) from a minimum to a maximum at a repetitive cyclic rate. The amplitude of such pressures is such that flow reversal occurs through the screen (20) and any fiber mat that tends to form on the inlet surface (23) is disrupted or fluidized.

Abstract: Pressure screening apparatus for screening a suspension of paper fiber stock employs a rotor in which a single impulse or foil member is carried or positioned to move along a discrete portion of the screen surface. This arrangement improves efficiency of operation of the pressure screen by reducing the rotational effect of the rotor on the stock suspension being screened and by providing a less disturbed screening region through which the single foil operates. Embodiments are shown in which multiple single impulse elements sweep over discrete portions of a screen and in which a single foil is combined, in screening apparatus, with multiple foils in accordance with the increase in consistency of the stock as it passes through the screen.

Abstract: Improved mist eliminator for use in pulp washers and the like, and method of use of such is disclosed. A cyclonic gas/liquid separator for a gas/liquid mixture flowing vertically upward therethrough includes a cylindrical housing, a top wall having a gas outlet, a gas/liquid inlet, and a cyclonic-flow-inducing vane assembly spanning the inlet. The improvement includes an annular wall transverse to the vane assembly positioned between the vane assembly and the housing. The annular wall, in combination with the vane assembly and housing, defines an annular volume wherein separated liquid may drain downwardly toward the annular wall substantially without resistance from the gas/liquid flow. A drain carries the separated liquid directly to a liquid reservoir.

Abstract: Pressure screening apparatus for screening a suspension of papermaking stock employing an enclosing housing and a cylindrical screen, with a drum type rotor, has the screen divided or formed with axially spaced annular screening zones and a corresponding number of annular reject collection areas, one for each screening zone. The collection areas are positioned so as to receive rejects from one of the screening zones only, while a rotor is formed with outlet openings that apply stock suspension to selected ones of the screening zones so that there is no mixing of rejects between screening zones, and each screening zone receives stock suspension for screening independently of the other screening zones.

Abstract: Methods and apparatus for recycling office waste paper and the like of the type having ink and laser print particles coated thereon. The waste paper is simultaneously pulped and ink particles dispersed by kneading the waste paper in the form of a high solids content aqueous mixture or sludge. After the simultaneous pulping and dispersing, no additional dispersion step is needed to form deinked paper stock. The high solids content aqueous mixture or sludge is diluted and forwarded to wet deinking separation devices such as a froth flotation unit or the like. The thus treated pulp is washed and results in the formation of a high quality pulp stock ready for bleaching and/or paper making procedures.

Abstract: A papermakers' screen basket for pressure screening of papermaking stock or for pressure filtering is formed with a support core formed with honeycomb like cells that extend radially in the direction of flow through the screen basket, and a thin covering having screening openings therethrough is supported on the inlet surface of the honeycomb cell core. The core is formed by rolling a flat section of core into the shape of a cylinder and welding the abutting ends to form a complete cylinder and then attaching a perforated or a mesh sheet-like metal covering against the core inlet surface, in which the thin sheet metal covering defines small openings, such as slots or apertures, leading into the honeycomb core, and is welded in place.

Abstract: A system and method for treating a waxed fiber paper product with a high wax content to remove a substantial portion of the wax content includes the pulping of the wax paper fiber at an elevated temperature in excess of the melting temperature of the wax to separate a pulp fraction and to form an emulsion of water and molten wax. The pulp fraction is separated from the emulsion by filtering in a reverse pressure screen in which a finely perforated screen defines a high pressure side and a low pressure side, and a major portion of the water/emulsion is removed from the suspension through the screen perforations leading from the high pressure side to the low pressure side, in which a rotor and foil arrangement within the reverse screen is operated under such conditions that the suspension at the high pressure side of the screen is maintained in a constant fluidized condition.

Abstract: Hydrocyclone cleaning systems and methods remove contaminants from a suspension of papermaking stock. A subsystem 10 employs forward cleaners for removing heavy contaminants while a subsystem 12 is fed directly from subsystem 10 and removes lightweight contaminants. The subsystem 12 also includes a through-flow cleaner which receives the rejects flow from a primary reverse flow cleaner and both systems are connected to a common surge tank arrangement. Both subsystems operate at low consistencies or high efficiency while the primary through-flow cleaner of subsystem 12 provides a system output having a consistency approximately twice as high as that of the input so that the overall operation operates both as a stock cleaner and a stock thickener.

Abstract: A rotary paper pulp refiner system and method includes a rotor having one or more refining elements mounted on a rotating shaft and complimentary non-rotating or stator elements defining with the rotating element a refining gap or gaps through which the paper stock material passes, and which the rotor is mounted for rotation on magnetic bearings that support the rotor shaft for rotation and define the axial and radial running position thereof. Optionally, a movable stator housing wall may also be controlled by a magnetic bearing.

Abstract: A reverse hydrocyclone cleaner (10) for the centrifugal separation of lightweight contaminants contained in a suspension of papermaking fibers is formed with an elongated hollow body (12) of circular cross section which converges uniformly from a first inlet end to a second apex end, in which the ratio of the length of the conical body to its largest diameter is at least approximately 20 to 1 and defines an included angle of less than 3 degrees.

Abstract: A hydrocyclone for separating lightweight contaminants from a suspension of papermakers'stock as a through-flow design in which an inlet section has a frusto-conical flow controlling wall and has a central flow stabilizer and a tangential inlet. The flow stabilizer has a paraboloid shape and defines with the flow control wall an annular flow space of constant area along the axial length of the flow stabilizer so that fluid entering a tangential inlet at the base of the paraboloid is caused to rotate about the flow stabilizer and is delivered to the interior of the hydrocyclone without a substantial change in axial velocity.