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: The gas and water content of crude oil flowing through a pipeline is measured using a flow restriction in the pipeline, a radioactive source for providing separate radiation energies for each component to be measured, a detector for detecting the radiation transmitted by the various components to generate a first set of signals, pressure gauges upstream of and in the flow restriction for providing a second set of signals, and a signal processor for correlating the signals to provide mass flowrate values indicative of the relative proportions of the components of the mixture. The temperature of the mixture in the flow restriction can also be measured and fed to the signal processor for ensuring that accurate values of flowrate are obtained when temperatures vary.

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: The present invention relates to a paving grade asphalt composition which comprises a blend of (a) a petroleum pitch obtained as a residue in the hydrocracking of hydrocarbon oils and (b) as a diluent therefor an unprocessed distillation residue having a minimum initial boiling point of at least 200.degree. C. obtained from bitumen from tar sands, or heavy oils or light oil from pure or mixed petroleum crude oils.

Abstract: An apparatus is disclosed for displacing a portion of liquid stored in a tank using impervious bladders formed with flexible membranes. The bladders are filled with material having a density greater than the density of the stored liquid and cover substantially the entire usuable bottom of the tank. The tank bottom also has unusable areas including inflow pipes, outflow pipes, heaters, support columns or floating roof support legs. Substantially rigid protectors are provided preventing the bladders from expanding into the unusable areas of the tank bottom.

Abstract: Lubricant compositions are disclosed in which a synergistic combination of low-volatility tri-substituted phosphite and low-volatility sterically hindered phenolic stabilizers provide surprisingly effective antioxidant qualities to lubricating oils selected from hydrotreated oils, poly-alpha-olefin oils and paraffinic white oils, and mixtures thereof.

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.