Abstract: An improvement to a hopper to promote the flow of solid particulate material includes mounting one or more walls of the hopper for limited oscillatory motion in a direction parallel to the wall and perpendicular to the desired flow direction, and then providing an actuator connected to the remainder of the hopper to impart such motion to the wall. The relative motion between the moving wall and the particulate material effectively rotates the friction force to the direction of relative motion, leaving the friction in the desired flow direction approaching zero. As a result, downward flow can occur on walls that are only shallowly inclined. The improvement is applicable to hopper-like structures in railroad cars and ships, where it facilitates discharge onto moving conveyors.

Abstract: A hopper that greatly reduces the tendency of the particulate material to form bridges within the hopper is shaped so that its walls slope downward more steeply at the bottom of the hopper and slope less steeply with increasing height above the outlet. In one embodiment the slope decreases continuously with increasing height above the outlet. In another embodiment the hopper is formed of successive sections, each joined around its circumference to the next-lower section, the wall of each section being less steeply inclined than the wall of the adjoining next-lower section. Exact relationships are given, relating the slopes of successive sections, and if the hopper is built in conformity with these relationships, arching of the particulate material is eliminated.

Abstract: Many types of processors of particulate materials operate more efficiently when they receive the particulate material in a steady stream. Most feeders tend to discharge in pulses. A hopper is interposed between the feeder and the processor. Surges in the feed rate are accumulated in the hopper, and lapses in the feed rate are compensated by the propensity of the hopper to discharge at a constant rate. Initiation of hopper flow is accomplished by use of a trap door. Mismatch between average feeder output rate and hopper discharge rate is corrected by use of an adaptive hopper having an outlet the size of which is slowly altered to maintain a constant amount of material in the hopper. A bypass hopper is used to control extremely variable input flow rates.

Abstract: In a vertical digester for producing chemical pulp, or other vessel for treating a slurry of comminuted fibrous cellulosic material, the cost of manufacturing the shell is significantly reduced by eliminating the external step increases in the digester shell. The digester shell has a substantially constant internal diameter from just below the inlet to just above the outlet, screen assemblies being provided by an internal transition (e.g. conical) having an angle of convergence of less than 40.degree. (e.g. about 10-25.degree.) above each screen assembly so that the slurry flows through the transition without bridging or hang-up, and a step increase, or other increase, in diameter back to the first diameter after the screen assembly.

Abstract: A chip bin construction, ideally suited for bins having a maximum diameter of twelve feet or more, uniformly discharges chips, after steaming, without the necessity of a vibratory discharge. A hollow transition portion is provided between a main body which is a right circular cylinder of a first diameter, and a nonvibrating discharge which has a second diameter typically 1/3 or less that of the first diameter. The hollow transition includes a first, uppermost, portion having a generally right rectangular parallelepiped configuration including opposite side faces having generally triangular shapes, and providing one dimensional convergence and side relief; a second portion tapering from a generally rectangular parallelpiped configuration at an upper part to a generally circular configuration at a lower part and having opposite side faces having generally triangular shapes which align with said first portion generally triangular shapes to define substantially diamond shaped wall portions.

Abstract: The interface is an apparatus that is attached to the outlet of a hopper to assist and control the discharge of particulate material onto the loading surface of a feeder, such as a moving belt. The interface results in a saving of 50 to 75 percent in the power required to drive the feeder. Three structural innovations contribute to this saving in power. First, a plate that extends vertically and in the direction of movement of the feeder is introduced into the stream of material within the interface to reduce downward pressure on the loading surface of the feeder. Second, the lower edge of the strike-off plate is arched upwardly, which reduces the power required for maintaining the shearing action. Third, the interface is provided with vertical skirts that prevent lateral spreading of the material so that a narrower feeder can be used.

Abstract: A chip bin construction, ideally suited for bins having a maximum diameter of twelve feet or more, uniformly discharges chips, after steaming, without the necessity of a vibratory discharge. A hollow transition portion is provided between a hollow substantially right circular cylindrical main body and a rectangular discharge. The hollow transition may have a substantially circular cross-section open top and a substantially rectangular cross-section open bottom and opposite non-vertical gradually tapering side walls. At least one feed screw may be mounted at the open bottom of the transition for cooperation with the discharge, and the feed screw(s)--or the equivalent--may provide for metering of the chips. Alternatively, the hollow transition portion may provide one dimensional convergence and side relief, and no screw feeders need be provided, in which case a conventional chip meter is used.

Abstract: A chip bin construction, ideally suited for bins having a maximum diameter of twelve feet or more, uniformly discharges chips, after steaming, without the necessity of a vibratory discharge. A hollow transition portion is provided between a hollow substantially right circular cylindrical main body and a rectangular discharge. The hollow transition may have a substantially circular cross-section open top and a substantially rectangular cross-section open bottom and opposite non-vertical gradually tapering side walls. At least one feed screw may be mounted at the open bottom of the transition for cooperation with the discharge, and the feed screw(s)--or the equivalent--may provide for metering of the chips. Alternatively, the hollow transition portion may provide one dimensional convergence and side relief, and no screw feeders need be provided, in which case a conventional chip meter is used.

Abstract: In a chip bin or similar cylindrical upright vessel for storing particulate material the interior generally vertical wall of the vessel has a surface configuration which reduces compression of particulates within the vessel so as to substantially prevent pluggage or particulate bridging. Three or more right circular cone frustrums having a larger diameter at higher portions than at lower portions are provided along the interior generally vertical, either one immediately adjacent the other without significant spacing between them, or in a discontinuous manner being spaced from each other a significant distance. The frustrums insure that the vertical pressure level throughout the vessel is less than about 250 psf (e.g. less than about 200 psf). The vessel may be constructed of concrete using slip forms, with the concrete providing both the exterior and interior of the vessel, or a steel shell may comprise the exterior.

Abstract: A versatile one-dimensional hopper is described as well as structures that result when the one-dimensional hopper is integrated with a conical bin and when the one-dimensional hopper is integrated with a V-blender. In combining the one-dimensional hopper with other structures, the diameter of the outlet is first specified, and then the slopes of the load-bearing surfaces are chosen to achieve specified flow characteristics. The load-bearing surfaces are then extended obliquely upward until, at some height their maximum dimension measured horizontally equals a value determined by the structure to which the one-dimensional hopper is to be attached. Where the surface of the bin or other structure is higher than this height, vertical surfaces that extend upwardly from the periphery of the one-dimensional hopper are provided for the purpose of connecting the one-dimensional hopper to the structure above it.

Abstract: An instrument for measuring certain physical properties of a sample of particulate material so that the flow characteristics of the material can be determined includes an improved compaction assembly having an upper piston that is surrounded by a retractable sleeve and further includes an improved test cell having cylindrical walls, having a failure outlet smaller than the diameter of the failure piston, and having a false bottom that can easily be removed from beneath a sample of compacted material to permit the failure portion of the test to be carried out. The tester can be used for determining the confined yield strength of the material, its bulk density, and its permeability.

Abstract: An improved flow-no-flow tester has two major advantages over its predecessor. First, it eliminates the need to invert the test cell after the compaction phase, thereby eliminating the possibility that failure of the compacted sample will occur before the failure load-measuring portion of the test can be done. Second, the improved tester determines the compaction load by measuring the force exerted by the sample against an upper piston, while a compressive force is applied to the sample by a lower piston. This results in greater accuracy than was obtained in the predecessor wherein the compaction load was taken to be the force applied to the compressing piston and which was in error due to the forces of friction and particle binding on the piston as it advanced against the sample. In addition, the improved tester minimizes the potential of particle binding during the failure portion of the test.

Abstract: An elongated, generally vertically extending reactor vessel for the production of hypochlorous acid by the mixing and reaction of a liquid alkali metal hydroxide and a gaseous halogen is provided with solids discharge handling apparatus connected to the bottom to remove the solid by-product. The discharge handling apparatus uses the solids to effect a seal to prevent the intrusion of outside air into the reactor and the escape of halogen and product gas to the outside atmosphere.

Abstract: Apparatus for densifying particulate solids and for removing air from the solids includes a screw feeder that conveys the material through a recirculation chamber, then into a high pressure shroud that is closed at its downstream end by a preloaded cover in yieldable sealing engagement with the downstream end of the high pressure shroud. In a preferred embodiment, the high pressure shroud includes a perforated section that extends upstream into the recirculation chamber so that as the particulate material is compressed by the screw in the high pressure shroud, air and some of the particles are expressed through the perforations and are contained by the recirculation chamber which directs the expressed particles downward into the screw which once again pushes them into the high pressure shroud.

Abstract: The discharge rate of a solid particulate material from a storage hopper is increased beyond the rate attainable by gravity flow along through the introduction of a pressurized gas into a plenum that lies over the discharge hopper. In one embodiment, a first pipe extends vertically downward from a storage hopper, and a second pipe of larger diameter is fitted over the lower end of the first pipe so that an annular plenum is formed between the pipes. A pressurized gas is injected into this plenum and results in an increase in the discharge rate. The discharge rate can be controlled by altering the pressure of the injected gas, and the flow can be rendered intermittent by opening and closing a gate valve at the outlet of the discharge hopper.

Abstract: A bin adapted for storing and dispensing particulate materials is formed by joining two or more bin modules of similar shape. The linear dimensions of the modules increase in a geometric series, with the smallest module being at the bottom. The modules are designed to prevent arching of the particular material to assure mass flow. Three embodiments of bin modules are described. In the first and the third embodiments, each module consists of two sections, but in a second embodiment the module consists of four sections. A bin constructed of these modules requires appreciably less head room than does a conical bin.

Abstract: A series of hollow cylinders are mounted inside the cylindrical portion of a solids blender to propagate the velocity profile from the bottom to the top of the cylinder and thus to extend the blending capacity of the bin to its entire length and volume. The invention can be used with funnel flow hoppers, mass flow hopper, and cone-in-cone mass flow hoppers. Ranges of the design parameters are described.

Abstract: A first body has a cylindrical section that is adjacent a conical section so as to form a constricted passage through which granular solids are forced under pressure. Passage through the constriction results in the application of shear forces to the granular solids which degrades some of the particles to create fines to fit between the larger particles and which induces interparticle motion that facilitates the compaction process. After passing through the constriction, the compacted solids are received in a cylindrical receiving chamber, into which a piston can be inserted for the application of direct compression forces. In a preferred embodiment, the granular solids are forced through several constricted passages in sucession, resulting in several stages of compaction prior to the final stage of direct compression.

Abstract: Apparatus and a test method for bench scale determination of whether a particulate material will flow under the action of gravity alone from an outlet in the bottom of a container. The apparatus includes a test cell having inclined conical side walls, and that is closed at its larger end by a plug having an inwardly-facing surface that is concave and conforms to a coaxial cone. In this way, cylindrical surfaces are avoided, and the shape of the space within the test cell offers minimal interference with the plastic stress field of the material. This testing method includes the novel step of inverting the test cell after consolidation of the test material but prior to application of the failure load.

Abstract: A continuous digester discharges pulp without mechanically engaging the pulp, by using one or more discharge transitions with one dimensional convergence and side relief. The transitions may be mounted within a pre-existing digester shell (after removal of the discharge rotor), and supported by a number of braces and/or a skirt shaped like a truncated cone. The operation of a digester, or other continuous vessel, may be controlled by automatically sensing the level of comminuted cellulosic fibrous material in the vessel and automatically controlling the introduction of dilution liquid into the vessel to discharge the material from the vessel in response to the sensing.