Abstract: A paraffinic solvent is mixed with bitumen froth containing water and solids. Sufficient solvent is added to induce inversion when the mixture is subjected to gravity or centrifugal forces. The emulsion reports to the water phase and a dry bitumen product is obtained.

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: A dispersant, such as sodium silicate, is added to the process water of the hot water extraction process which recovers bitumen from oil sands. The dispersant disperses the ultrafine (less than 300 nm) particles, to reduce the formation of flocs and sludge in the tailings pond. The volume of the pond is such that the retention time of process water is sufficiently short (less than 6 weeks when using sodium silicate) to avoid reforming flocs from the dispersed ultrafines. The ultrafines content in the process water builds up as the water is repeatedly recycled from the pond to the extraction process. The ultrafines content stabilizes at a steady state concentration as some ultrafines are continuously removed from the process water when the tailings are delivered onto the "beach" of the pond and become trapped in the sand.

Abstract: Middlings from the primary separation vessel ("PSV") are recycled through a line to the PSV. The middlings are aerated with fine air bubbles using in line eductor/aerator assemblies. The aerated middlings are mixed as they are pumped through a line back to the PSV. Bitumen recovery from the PSV is increased as a result.

Abstract: Aerated bitumen froth containing bitumen, water, air and solids is the product of the hot water extraction process for recovering bitumen from oil sand. Measurements related to the water content of the froth can be obtained by measuring its resonant frequency in a calibrated output, open-ended microwave cavity. By also measuring the bulk density of the froth and assuming a constant relationship for the solids content, one can compute from the assembled data the output quality of the froth. The measurements can be taken repetitively at the vessel as the froth is produced and used to almost instantly provide froth quality information.

Abstract: The washer comprises an open-topped vessel having a tube mounted vertically and centrally therein. Post-primary bitumen froth is fed to the upper end of the tube. Pairs of down throw and up throw propellers mounted to rotate in the tube act to shear the froth as it passes down through the tube. At its lower end, the tube is closed off by a transverse wall. Slots are formed in the tube side wall to provide an exit. The sheared mixture thus changes direction as it leaves the tube. In the vessel chamber, solids and water sink downwardly and are removed as tailings through a bottom outlet. The sheared aerated bitumen rises and forms a new forth that is recovered in a launder. Middlings are withdrawn from the chamber and recycled to join the feed. The product froth is reduced in water and solids relative to the feed froth.

Abstract: As-mined, naturally water-wet oil sand is mixed at the mine site with hot water and NaOH to produce a slurry containing entrained air. The slurry is pumped through a pipeline and is fed directly to a conventional gravity separation vessel. The pipeline is of sufficient length so that, in the course of being pumped therethrough, sufficient coalescence and aeration of bitumen occurs so that, when subsequently retained in the gravity separation vessel under quiescent conditions, a viable amount of the bitumen floats, forms froth, and is recovered.

Abstract: A process is disclosed for the removal of hydrocarbons such as bitumen or heavy fuel oil from hydrocarbon contaminated sludge, or particulate solid material or the like non-homogenous material after appropriate conditioning, such as by ball milling, with the conditioned material being aerated and then fed substantially tangentially into a substantially vertical cyclonic separator vessel to cause the hydrocarbons to which air bubbles have become attached to tend to float as a froth to the top of the vessel, with the remaining solids sinking to the bottom of the vessel. The hydrocarbon containing froth is then removed from the top of the vessel, and the remaining solids removed from the bottom of the vessel. This pneumatic flotation process obviates the need to add chemicals such as wetting agents or promoters.

Abstract: An aperature is formed in the bottom wall of the launder. A downwardly extending container communicates with the aperture. A weir is positioned immediately downstream of the aperture. The container and weir combine to form a separator. In the launder, free water and solids contaminants settle and form a bottom layer of dirty water. The layer is diverted into the container through the aperture and the weir temporarily retains a small head of it. Temporary retention in the separator therefore generates a vertical fluid column comprising an upper layer of relatively clean froth and a lower layer of dirty water, said layers having an ascertainable interface. The elevation of the interface is monitored and contaminated fluid is withdrawn from the container as underflow at a rate controlled to keep the interface elevation substantially constant. The froth overflowing the weir is reduced in water and solids relative to the original froth issuing from the flotation vessel.

Abstract: The mixer circuit comprises a vertically oriented, open-topped mixer vessel having a cylindrical side wall terminating with a shallow conical bottom. The bottom wall forms a central bottom outlet. Recycled slurry and fresh water streams are fed tangentially to the inner surface of the vessel, thereby forming a vortex. The oil sand enters as a continuous, free-flowing stream moving along a downward trajectory; the stream impinges the vortex, wherein it is dispersed and mixed to create slurry. The slurry exits through the bottom outlet, is screened to remove oversize material, and enters a holding vessel. Part of the slurry in the holding vessel is recycled to the mixer vessel through a pipe loop incorporating a pump. The slurry is energized by the pump and functions to maintain and partly create the rapidly moving vortex that carries out the mixing and lump-disintegration actions. The balance of the slurry in the holding vessel is pumped out as product.

Abstract: The present invention is based on the following:(1) that when tar sand is conditioned and diluted in the hot water extraction process, there are two classes of anionic surfactants (originating from carboxylate and sulfonate groups) present in the process water;(2) that each of these surfactants has the potential to dominantly influence the maximizing of primary froth production by the process;(3) that it is possible for a particular extraction circuit to determine the critical free surfactant concentration in the process water at which primary froth extraction is maximized for each of the two classes of surfactant;(4) and that it is possible to determine which of the two classes of surfactant will first (that is, at lowest NaOH addition) dominate the process when a particular tar sand feed is being processed.The present invention therefore involves:determining the critical free surfactant concentrations ("C.sub.cs.sup.O " and "C.sub.ss.sup.

Abstract: A bucket wheel assembly for excavating solid material from the ground which can be slurried with water has a series of buckets mounted on a framework rotatable about a substantially horizontal axis, the buckets, being secured to the framework at spaced positions around the periphery, and each bucket having a leading edge portion engagable with the ground as the framework rotates to cause material to be scooped from the ground into the bucket. Sets of nozzles are mounted around the framework, each set of nozzles being located between an adjacent pair of buckets and spaced in the direction of movement of the buckets from the leading edge portion of a following bucket. A rotary valve is connected to the nozzles and to a source of liquid under pressure.

Abstract: A low temperature process for separating bitumen from tarsands comprises slurrying tarsands in water at a temperature in the range of above about freezing to 35.degree. C., preferably in the range of 2.degree. to 15.degree. C., mixing said aqueous slurry with a conditioning agent for a time sufficient to release bitumen from tarsands and to uniformly disperse the conditioning agent on the bitumen, and subjecting the resulting slurry to froth flotation for recovery of a bitumen product and production of sand tails.

Abstract: A system is provided for controlling the feed rate of material being loaded onto a conveyor train of variable configuration to prevent overloading. The system involves monitoring the power drawn by the various drive motors of the train to establish which is the limiting conveyor under prevailing operating conditions. The instantaneous weight of feed material loaded onto the conveyor train, at its input end, is continuously measured and the current average feed rate is computed from the instantaneous weights measured over a pre-set time interval. A rolling average of the total load to be carried by the limiting conveyor downstream is computed from the average feed rate, taking into account the length of the limiting conveyor. The feed rate is then adjusted in response to the computed rolling average to thereby avoid overloading the limiting conveyor and optimize loading of the conveyor train.

Abstract: An improvement is provided to the known hot water process for extracting bitumen from mined oil sand. More particularly, a methodology is provided for the production of microbubbles of air, and it has been found that the so-produced microbubbles can be used in the primary flotation/settling step of the hot water process to yield increased bitumen recovery. More particularly, a steam stream and an air stream in admixture are injected via a submerged nozzle into a flowing aqueous stream. A plurality of finely dispersed microbubbles are formed. These microbubbles have a diameter less than about 100 microns. The stream of microbubbles is injected into the diluted aqueous tar sand slurry formed in the hot water process. The injection is practiced following the conditioning step and prior to the introduction of the slurry into the flotation/settling step.

Abstract: Froth, produced by induced air flotation in the hot water process circuit for extracting bitumen from tar sand, is recycled and added to the fresh slurry being introduced to the primary separation vessel. An increase in bitumen recovered as primary froth from the circuit is produced.

Abstract: A basket is removably inserted in the upper end of each drain tube in those interbed assemblies of a catalytic tower whose catalyst beds are to be removed upwardly by vacuuming. The basket has a grid for a bottom wall, so that catalyst particles thereabove are retained but fluid being treated in the tower can easily pass therethrough. The provision of the baskets makes it possible to downwardly drain spent catalyst from the lower bed sections while simultaneously vacuuming it upwardly from the upper bed sections.

Abstract: The hot water process is controlled in response to viscosity measurements taken in situ in the middlings in the primary separation vessel. The viscosity in the middlings is found to vary. Therefore, the layer of maximum viscosity is located and the viscosity at this depth is monitored. Adjustments are made to the process to keep this maximum viscosity below a pre-determined limit.

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: A steel connector for joining the steel cable ends of a conveyor belt is provided. The connector comprises a pair of tubular sleeves--one of which is slipped onto each cable end. Each sleeve has a bore having an inner section of reduced diameter relative to the outer section. The cable end is expanded radially, by driving a cone into its end, and then the expanded end is wedged tightly into the inner section of the sleeve to fix them together. Bridging members are threaded into the outer sections of the two sleeves to hold them together in lineal alignment. The bridging members are operative to permit the sleeves to flex relative to each other.