Abstract: A self-tracking roller comprised of a plurality of individual elements is presented. These elements alternate between evenly distributed idler rings and spacer rings arranged in two groups having a central space therebetween. This central space permits two superimposed dual belts to form a sandwich for conveying solid material therein. Each idler or tracking ring has a conical shaped configuration which acts to urge a conveyor belt thereon toward the center of the roller. The relative dimensions and number of rings may be flexibly varied depending on the application. The result is a self-tracking roller aptly suited for use in conjunction with dual or sandwich conveyor belt systems.

Abstract: Apparatus for compacting loose, spongy or disintegrated solid material in which a pair of conveyor surfaces, one of which is fluid-pervious but solid-impervious, are disposed in convergent spaced relation with one another to form a compacting zone. Fluid is removed from the compacting zone through the fluid-pervious conveyor surface. Material to be compacted is supplied to the divergent end of the compacting zone while the surfaces are moved towards the convergent end of the compacting zone to cause the material to be compacted.