A method for controlling the solids distribution in a bitumen froth produced when processing an oil sands ore having a d.sub.50 of about 250 m or greater and a d.sub.90 of about 450 m or greater is provided comprising adding a high-fines material having a d.sub.50 of about 50 m or less and a fines content of about 40% of the solids or greater to the oil sands ore to form an ore blend; and processing the ore blend in a water-based bitumen extraction process to produce the bitumen froth.

A process for dewatering oil sand fine tailings is provided and comprises a dispersion and floc build-up stage comprising in-line addition of a flocculent solution comprising an effective amount of flocculation reagent into a flow of the oil sand fine tailings; a gel stage wherein flocculated oil sand fine tailings is transported in-line and subjected to shear conditioning; a floc breakdown and water release stage wherein the flocculated oil sand fine tailings releases water and decreases in yield shear stress, while avoiding an oversheared zone; depositing the flocculated oil sand fine tailings onto a deposition area to form a deposit and to enable the release water to flow away from the deposit, preferably done in a pipeline reactor and managing shear according to yield stress and CST information and achieves enhanced dewatering.

Direct steam injection (DSI) heating techniques can use a heater to heat a process stream in bitumen froth treatment. The DSI heater can include a diffuser with multiple side-by-side rows of outlets perpendicular to a longitudinal axis of the diffuser, and a piston plug that moves axially within the diffuser to selectively cover rows of outlets to vary steam injection. The piston plug has first and second annular seals and is moved between different axial positions in a stepwise fashion such that when one or more rows of outlets are completely covered, the first annular seal is located in between adjacent rows and the second annular seal abuts against the diffuser to inhibit passage of steam so as to prevent cavitation. The DSI heater can include various other features, such as particular seal unit constructions and diffuser outlet configurations.

A method of removing fines and coarse particles from tailings comprises forming a slurry comprising water and oil sands and separating bitumen from tailings comprising fines and coarse particles. Functionalized nanoparticles each comprising a core of carbon nitride and functionalized with one or more exposed cationic groups are mixed with the tailings. The functionalized nanoparticles and the fines interact to form agglomerates comprising the functionalized nanoparticles and the fines attached to the one or more exposed cationic groups. The agglomerates are removed from the tailings to form an aqueous solution having suspended therein fewer fines and coarse particles than are suspended within the tailings.

A method for pre-treating bitumen froth for mixing with solvent for froth treatment includes heating the froth to a froth-solvent mixing temperature below the solvent flash temperature and suitably high to provide reduced bitumen viscosity sufficiently low for complete mixing of the solvent and the froth prior to introduction into a separation apparatus. A method of improving energy use in froth treatment includes reducing heat provided to the solvent, increasing heat provided to the froth prior to adding the solvent to reduce bitumen viscosity and adding the temperature-reduced solvent to the heated froth. A froth treatment separation process includes trim heating first and second solvent streams to adjust the first and second stage separation temperatures.

A method is provided for controlling bitumen recovery from an oil sands ore body in a bitumen extraction process by establishing and using a predictive ore processability model that accounts for multiple ore characteristics in planning ore deliveries from different locations of the ore body to produce a blended ore feedstock.

A process for treating a bitumen froth comprising bitumen, solids and water to produce a deasphalted oil product is provided comprising optionally diluting the raw bitumen froth with a diluent to form a diluted bitumen froth; separating the raw or diluted bitumen froth into a light bitumen fraction and a heavy bitumen fraction comprising bitumen, fine solids and water; mixing the heavy bitumen fraction with a first solvent to form a solvent/bitumen mixture; and introducing the solvent/bitumen mixture into a first extraction vessel operating at a temperature and a pressure such that the solvent is at or near supercritical conditions to form a heavy phase comprising asphaltenes, solids and water and a light phase comprising deasphalted oil.

A water extraction process for separating bitumen from tar sands comprises slurrying tar sands in water, mixing the aqueous slurry with a magnetic substance for a time sufficient to release bitumen from tar sands and to uniformly disperse the magnetic substance with the bitumen, and subjecting the resulting slurry to froth flotation for recovery of a bitumen product and production of sand tails. The magnetic substance may comprise a magnetic surfactant. Alternatively, the magnetic substance comprises a magnetic nanoparticle together with a frother having the characteristics of methyl-isobutyl-carbinol and can be mixed with the aqueous slurry by attrition scrubbing or by flotation cell mixing. The magnetic substance may be recovered for further reuse by applying a magnetic or electromagnetic field to the tailings. The process may suitably applied in both so-called hot water extraction processes as well in an ambient temperature (from about freezing to 35 C.) process.

Products from a high pressure processing system are separated and purified. The processing system is adapted for pressurizing and heating a feed mixture comprising carbonaceous material(-s) in the presence of homogeneous catalysts and liquid organic compounds to produce a converted feed mixture. The converted feed mixture is cooled and depressurized, and then separated into: a gas phase, an oil phase, and a water phase comprising liquid organic compounds and dissolved homogeneous catalysts comprising potassium and/or sodium. The liquid organic compounds and dissolved homogenous catalysts are at least partly recovered from said water phase, thereby producing a first water phase stream enriched in liquid organic compounds and homogeneous catalysts and a second water phase stream depleted in liquid organic compounds and homogeneous catalysts. The first water phase is at least partly recycled to the feed mixture, with a bleed stream being withdrawn therefrom prior to recycling.

A process for the extraction and recovery of bitumen from oil sands using deionized silicate solutions. Bitumen is recovered in a process comprising contacting a deionized silicate solution with an ore sand oil to produce a froth comprising bitumen and a tailings stream comprising water, sand and clay fines and optionally unrecovered bitumen. Preferably the tailings stream is dewatered and recovered water may be recycled to the extraction process.