Abstract: Particlized mineral material, such as gold ore, silver ore, or coal, is subjected to a leaching process in a manner to maximize treatment effectiveness even when the particlized mineral material contains small fines. The material is slurried with a flocculating material and fibers, such as cellulosic fibers, fiberglass fibers, or ceramic fibers, and a liquid, and then is passed to the top of a leaching reactor. The slurry is continuously passed downwardly in the reactor while the leaching liquid, such as a cyanide solution, is passed counter-current to the slurry. Leaching liquid is removed from the top of the leaching reactor by a stilling well, and then passed through a carbon adsorber and reintroduced into the reactor. Leached slurry is passed to a continuous washing station being utilized as a slurrying liquid for the particlized mineral material.

Abstract: A method and apparatus for continuously treating cellulosic chips to prevent degredation of the chips as a result of mechanical action exerted on the chips by a scraper. A false bottom is provided in a vessel with the scraper mounted for rotation about a vertical axis just above the false bottom, a large central opening being provided in the false bottom. The scraper removes chips from the vessel through the false bottom opening to a bottom portion of the vessel. The temperature within the vessel at the area of the scraper is maintained at a first temperature that is low enough so that loss of strength of the chips material does not result from mechanical action exerted on the chips by the scraper. Liquid is introduced into the vessel bottom portion at a second temperature that is approximately at the cooking temperature for effecting digestion of the chips, and substantially higher than the first temperature.

Abstract: A high transfer pressure device, and method, especially adapted for continuously conveying hard particulate material such as coal; and a screen specifically for use in such conveying. The high pressure transfer device includes a pocketed rotor containing a pair of diametrically through-going pockets perpendicular to each other, a housing enclosing the rotor and having four ports spaced around the periphery thereof, and a screen operatively associated with the rotor or the ports for screening out particles above a predetermined size that are conveyed in liquid passed through the device. Preferably the screen is associated with one of the ports of the housing and fluid injection nozzles are associated with the screen for injecting liquid under pressure toward the screen to effect dislodgement of any particles that may be lodged in the screen and thereby prevent damage to the screen. The operation of the fluid injection nozzles is timed to the rotation of the rotor.

Abstract: A high pressure transfer device and a method of continuously conveying a liquid suspension of particulate material utilizing the transfer device are provided. The device includes a pocketed rotor rotatable in a housing, with a center screen mounted in each rotor. The screen is mounted within each pocket interior so that as liquid under pressure enters the pocket through its inlet the screen will move to enlarge the volume between the inlet and the screen. This is accomplished by forming each screen as two screen portions and mounting the screen portions for pivotal movement with respect to a center post extending in the pocket coextensive with the rotor axis of rotation. Stops are provided extending from the pocket walls to prevent the screen portions for pivoting into alignment with the pocket inlet or outlet, and each pocket preferably has a substantially circular cross-sectional internal configuration.

Abstract: A pump for pumping high consistency materials such as paper pulp having a consistency of about 8% or more. The pump includes a pair of rotors disposed in a pumping chamber, and a number of blades extending radially from each rotor, each blade mounted for cooperation with a circumferential portion of the other rotor in sequence during rotation of the rotors in operation. The blades are suitably constructed so that during normal pumping of high consistency material they can produce a head of about 10-170 ft., remaining rigid during normal pumping. However, the blades will flex out of engagement with tramp metal or the like when encountered thereby so that no damage to the pump components results during normal operation. A relatively large clearance can be provided between each blade and its cooperating circumferential portion of the opposite rotor. The pump is especially utilizable in pulp treatment systems between vessels adapted to have high density cellulosic pulp therebetween.

Abstract: A method and apparatus for screenless treatment of cellulose fiber material without channeling of treatment liquid through a fiber material column being treated. An inner vertical vessel extends into an outer vertical vessel which has a larger diameter than the inner vessel, and an annular space in the outer vessel is defined by a portion of the inner vessel extending into the outer vessel. At least three baffles extend through the annular space into the area of the outer vessel below the inner vessel to define at least three distinct flow areas, and an outlet nozzle is provided in each of the flow areas. Liquid is withdrawn from the annular space through at least two of the flow areas, while liquid is backflushed into one of the flow areas.

Abstract: In an apparatus for treating cellulose pulp with oxygen gas by passing the pulp and oxygen gas through a reaction vessel at elevated temperature and pressure, the improvement whereby the exothermic heat of reaction is controlled and the temperature of the pulp being treated is maintained below the point where the pulp would be degraded, the improvement comprising means for withdrawing oxygen gas from the vessel after the gas has been in contact with the pulp, dividing the withdrawn gas into two portions, cooling one of the portions to remove water vapor therefrom, recombining the gas portions whereby the resulting gas has a lower temperature than the gas withdrawn from the vessel and returning the resulting gas to the vessel for further contact with pulp therein, the amount of gas withdrawn from the vessel and the degree of cooling of the cooled portion of withdrawn gas being regulated to maintain the temperature within the vessel below the point where the pulp is degraded.

Abstract: A process for continuously digesting cellulosic fibrous material wherein the degree of delignification of the cellulosic fibrous material in the digestion zone is continuously determined and monitored by determining the exothermic heat of the delignification reaction taking place in the digester. The exothermic heat of the delignification reaction is determined by measurements of the temperature rise occurring in the delignification zone and the heat capacity of the cellulosic material and digesting liquor.

Abstract: A method and apparatus for continuous oxygen bleaching of cellulosic pulp is provided utilizing first and second pressurized chambers with a number of tubes in fluid communication with both of first and second chambers. Oxygen bearing fluid is intimately mixed with digested cellulosic pulp and is continuously fed under pressure to the first chamber. Communication is selectively provided between the first and second chambers through at least one of the tubular members to allow passage of pulp from the member to the second chamber. The tubular member through which pulp flows to the second chamber is progressively changed as are the members through which passage is blocked, so that the pulp remains within each tubular member sufficient time to allow oxygen-bleaching thereof without degradation, and passes through the members without channelling. The oxygen bleached pulp is continuously discharged from the second chamber. The passage of pulp through the tubular members may either be downwardly or upwardly.

Abstract: A chips bin that allows thorough steaming of the chips in the bin without blockage of the chip flow. A chips bin with a vibrating discharge includes an activator cone and a number of support arms extending from the activator cone to the bottom portion of the bin. A number of steam ports are formed in each of the supporting arms and steam is introduced into the supporting arms and underneath the activator cone. The steam ports are formed in sidewalls of the supporting arms, and steam is introduced both underneath the bottom portion of the cone and underneath a top portion of the cone.

Abstract: An apparatus and method for the treatment of cellulosic fiber material with maximum efficiency while minimizing capital costs. Fiber material entrained in digesting liquid is impregnated with the liquid in an impregnation vessel, sluiced to a separate digesting vessel, and from the digesting vessel sluiced to one or more separate washing vessels without a significant reduction in pressure. Countercurrent washing is effected in the washing vessel(s). Digesting liquid withdrawn from the digesting vessel is heated in a transfer line back to the impregnation vessel.

Abstract: An apparatus and method for the digestion of cellulosic fiber material providing pulp of very uniform quality. Cellulosic fiber material entrained in treatment liquid is fed into a top portion of a first vertical treatment vessel, impregnation of the fiber material with treatment liquid taking place in the first vessel. A first flow path of fiber material entrained in and impregnated with treatment liquid is established from the bottom of the first vessel to a top portion of a separate second vertical treatment vessel, liquid substantially filling the second vessel. Liquid is withdrawn from the top portion of the second vessel (without screening) and a second flow path is established of the liquid withdrawn from the second vessel back toward the bottom portion of the first vessel, heating of the liquid during transport in the second flow path taking place.

Abstract: An apparatus for thickening pulp at the bottom of a diffusion washing tower. Two sets of concentric screens are provided, each screen set comprising a plurality of radially spaced screens, the screens of one of the screen sets being radially offset from the screens of other screen sets. A plurality of hollow mounting arms each commonly mount the screen sets and are in operative fluid communication with at least some of the screens of the screen sets. Screened liquid is withdrawn from the hollow mounting arms, and the hollow mounting arms and screen sets are axially reciprocated during the screening operation. Control of the homogeneity of the pulp is effected by preventing fluid communication between the interior of screens of the different screen sets, and two separate withdrawal devices are provided, one for withdrawing liquid only from one of the screen sets, and one for withdrawing liquid only from the other of the screen sets.

Abstract: A method and apparatus for presteaming of wood chips and the like. The chips are treated in a vertical presteaming vessel with steam under low pressure, and removal of the air from the chips is facilitated by maintaining the presteaming vessel substantially at or near atmospheric pressure. An exhaust fan, controlled by a pressure probe in the presteaming vessel, may be provided for maintaining the pressure in the vessel. The amount of air that can enter the vessel through the chips inlet is minimized by an inclined rotating screw assembly with a partial flight which elevates the packs and chips to form an isolation seal at the chips inlet into the vessel.

Abstract: Apparatus and method for digestion of cellulose material in a continuous digestion process, that do not require screens in the outlet of the digesting zone. Cellulose chips and digesting liquid at relatively low temperature are introduced into a relatively long and thin cylindrical impregnation vessel, having a first diameter. The chips from the impregnation vessel pass into a digestion vessel having a second diameter substantially greater than the first diameter, the outlet for the impregnation zone into the digestion vessel being disposed well into the digestion vessel and below an outlet(s) disposed in the top of the digestion vessel, and form a chips column in the digestion vessel.

Abstract: A gasification process in which gasification of lump size gas producing material, such as coal, is carried out under high pressure on a fixed-bed principle with a continuous feed of coal particles thereto, the continuous feed being accomplished by feeding coal of an appropriate particle size range into a volume of liquid within a first confinement path through a free surface thereof exposed to atmospheric conditions, collecting successive incremental volumes of particles and entrained liquid and transferring them into a liquid within a second circuitous confinement path maintained under pressure by virtue of the exposure of the free surface of a volume thereof with the gasification pressure conditions, conveying the particles of the incremental volumes communicated with the second path through a pumping action upstream of the particle communication therewith, collecting the particles in the volume and moving them upwardly through the free surface thereof into the gasification zone.