Abstract: Porous gypsum granules are produced by adding powdered plaster to a stable aqueous foam and agitating the foam until granules of desired size are formed. Agitation is terminated before the foam collapses, but when the foam has subsequently collapsed the damp granules are recovered and dried. The product granules have a generally spheroidal shape mainly in the size range 0.25 to 2 mm, with a fine compact outer surface layer and a coarser interior with voids which confer high absorbency. These can be used as carriers for active materials such as herbicides or insecticides for agricultural or horticultural purposes or as fillers for plastics. Apparatus for continuously mixing fluid materials and suitable for use with foam and gypsum consists of a trough-shaped conveyor with a series of rotary agitators spaced along it.

Abstract: An improved worm mixer for use in containers having pivotally mounted wires attached to the superficies of the worm and being parallel to the axis of the worm so as to prevent residue from forming on the walls of the container.

Abstract: A cone-and-screw mixer for mixing powders, granulates or polydisperse granular materials having a conical vessel accommodating a screw simultaneously rotating about its own axis and around the axis of the vessel. The mixer is provided with an inlet opening located in a cover, a pipe fitting located in the bottom and an overflow opening located between the inlet opening and the upper flight end of the screw. The area of the overflow opening is preferably equal to that of the inlet opening, whereas the angle included between the vertical planes passing through the mixer axis and through the points being least distant from each other and located at the edges of the overflow and the inlet openings is not less than 0.35 rad.

Abstract: A mixer is disclosed of the type including a downwardly tapering conical wall and a rotating worm or screw which rotates both about its own axis and which rotates about a conical path along the inside wall of the vessel to effect mixing. At the bottom of the vessel is a flanged opening, and a bearing housing sealingly engages the flanged opening of the mixing vessel from below. The bearing housing includes a product outlet tube extending straight vertically downwardly therefrom.

Abstract: Cellulose fibers are treated by providing the fibers in a 10-90% concentration in liquid, and applying elastic pressure shocks to the fibers for a duration not exceeding one second and of a magnitude causing the pressure in the interior of the fibers to exceed 0.2 atmospheres excess pressure. Thereafter the fibers are permitted to expand. The pressure shocks cause liquid to be expelled from the fibers without permanent deformation of the fibers occurring. When the fibers expand, liquid is adsorbed. These steps are repeated until the fibers are completely impregnated with liquid. This prevents the formation of fiber knots when the fibers are substantially dried before being formed into paper. The elastic pressure shocks can be applied by a rotating paddle wheel which intermittently elastically compresses the fibers against an elastic surface of a container.

Abstract: A mixer with a substantially conical mixing chamber supported vertically with its apex lowermost. A tapered auger is situated in the mixing chamber and mixer drive is provided at the base of the mixing chamber. The narrowmost end of the tapered auger is connected to the drive such that the auger rotates around its own axis and its upper end rolls around the upper periphery of the mixing chamber.The upper end of the auger has a wheel to allow the auger to freely roll around the upper periphery of the mixing chamber and to insure that the auger does not contact the walls of the mixing chamber. The wheel is held in contact with the upper periphery of the mixing chamber under the action of the weight of the auger.

Abstract: Mixing apparatus having a vertical mixing vessel and a mixing screw rotatable therein, the lower end of said screw being supported by bearings and a universal joint. One of the universal joint parts is below the vessel bottom and the other part extends through said bottom. The upper surface of the other part is in the shape of a sphere segment and is sealed in the bottom aperture by a sealing ring.

Abstract: A mixing device comprising a vessel and an agitator extending into the vessel in which the vessel is hermetically sealed from the atmosphere by a flexible member detachably connected with the wall and the agitator shaft. Means are provided to maintain the agitator shaft in a fixed angular position during the stirring operation.