Abstract: A batter board is interposed between an upper conveyor belt, that is discharging granular material, and a lower conveyor belt that is receiving it. The batter board is adapted to deflect the downwardly arching stream of material, to laterally adjust the location on the lower belt where the material is deposited. The extent of deflection practised is controlled in response to measurements which monitor the downstream belt side travel of the lower belt. The position of the batter board is adjusted with hydraulic actuators protected with a shock absorbing system.

Abstract: The flat-plate type wind turbine rotor blade comprises a rigid spoke having a single thin flexiblie skin associated therewith. The skin is formed to provide a delta-wing and a flap extension. The delta-wing and the flap extension are angularly disposed at about 25.degree. to each other. The spoke lies along the junction of the delta-wing and the flap extension. A substantially rigid peripheral member extends along the margin of the skin. The peripheral member and the spoke are joined to provide a frame to which the skin is secured. Arrays of parallel reinforcing rib members extend between the spoke and the peripheral member. These rib members are mounted on the pressure surface of the skin. The ribs on the delta-wing are positioned at an angle of about 60.degree. from the axis of the spoke; the ribs on the flap extension are positioned at an angle of about 75.degree. from said axis. They therefore coincide with the main flow paths of the air flow over the blade surface.

Abstract: The primary tailings and middlings are combined and fed to a vessel having the general form of a deep cone thickener. The feed is deflected outwardly and generally horizontally by a baffle, as it is delivered to the vessel. Simultaneously, the outwardly radiating layer of newly added feed is contacted from below by an upwelling stream of aerated middlings, which stream moves in parallel with the aforesaid layer. Bitumen froth is formed and recovered. The upwelling stream is provided by circulating middlings through eductor/aerator assemblies and a plenum chamber mounted centrally in the body of middlings in the vessel. A generally circular circulation of middlings is generated. In this manner, the newly added bitumen is quickly and efficiently recovered. Recirculation of middlings to the aeration zone yields an additional recovery of bitumen. Use of the deep cone ensures that the tailings from the vessel are relatively low in water and bitumen content.

Abstract: The hot water process is sensitive to the nature of the tar sand feed, which varies. An alkaline process aid, usually NaOH, is normally added to the conditioning step of the process and is needed to obtain good bitumen recovery from most tar sand feeds. The invention is based on the discovery that, for a particular extraction circuit used, there is a single value of free surfactant content in the aqueous phase of the process slurry which will yield maximum primary froth recovery regardless of the type of tar sand feed used.