PROCESS AND SYSTEM FOR RECOVERING OIL FROM OIL BEARING SOIL SUCH AS SHALE AND TAR SANDS AND OIL PRODUCED BY SUCH PROCESS

摘要

In a first aspect, oil bearing soil, such as oil shale or tar sands, is contacted in a contacting zone with a liquid medium comprising water and a lipophilic solvent which is miscible or soluble with water. In a second aspect, the medium can include a yield improving agent comprising a water soluble acidic ionic salt or a water soluble ionic acid. The contacting produces an emulsion which comprises the oil from the oil bearing soil and the liquid medium. The inorganic portion of the soil is dispersed in the emulsion and it is separated from the emulsion by gravity or other suitable means. The emulsion is broken by an emulsion breaking agent into two phases. The two phases are allowed to separate into two layers. The first layer comprises the oil and minor amounts of the liquid medium. The second layer comprises the liquid medium and minor amounts of the oil. The first layer is then recovered. The medium from the second layer can be recycled into the contacting zone. In a third aspect, tar sands are contacted first with a liquid medium comprising an intimately mixed phase emulsion of a immiscible solvent and an aqueous solution containing a surfactant and a noncaustic alkali compound. The bitumen released is recovered and the remaining sand is contacted with a second liquid medium comprising an aqueous solution containing a surfactant and a non-caustic alkali compound. The bitumen further released is recovered. Additional contacting of the remaining sands with additional volumes of the second liquid medium may provide further recoverable bitumen.