| 摘要 |
The present invention involves a method and apparatus for enhanced recovery of petroleum fluids from the subsurface by injecting a hydrocarbon solvent vapor in contact with the oil sand formation and the heavy oil and bitumen in situ. Multiple propped vertical hydraulic fractures are constructed from the well bore into the oil sand formation. The hydrocarbon solvent vapor and a non-condensing diluent gas are injected into the well bore, fill the hydraulic fractures, and thus contact and diffuse into the in situ bitumen. The hydrocarbon solvent vapors diffuse into the bitumen from the vertical faces of the propped fractures. The bitumen softens and flows by gravity to the well bore, exposing fresh surface of bitumen for the process to progressively soften and mobilizes the bitumen in a predominantly circumferentially, i.e. orthogonal to the propped fracture, diffusion direction at a nearly uniform rate into the oil sand deposit.
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