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Some of the most promising areas for the extraction of heavy oil, maltha and asphalt in the eastern part of the Siberian platform are the southern and southeastern slopes of the Anabar anteclise. Using solvents for mining heavy oil and natural bitumen in a permafrost zone is the only option to steam injection, which is obviously cost ineffective there. Advantages of the solvents include convenience of transportation to field and storage stability. Moreover, the solvents have sufficiently high solubility with respect to heavy oil and natural bitumen, they facilitate oil transportation and don't require sophisticated equipment for their separation from the oil. The authors proposed criteria for selection of effective hydrocarbon solvent to be used in fractured porous reservoirs located in permafrost conditions. In accordance with the criteria, a solvent is designed for heavy oil and natural bitumen extraction. Its composition contains aromatic hydrocarbons, surfactants, thickeners and diesel. In a laboratory, physicochemical characteristics of the solvent were defined, as well as investigated its interaction with a sample of bitumen and with drilling mud. To find the solvent's capacity to displace oil, an experimental work was carried out at the facility UIPK-02M on samples of Middle-Upper Cambrian deposits from the southern and southeastern slopes of the Anabar anteclise. The method to determine the displacing capacity of the solvent consists in its filtration through the sample and substituting the fluids located in the pores. [ABSTRACT FROM AUTHOR]

Vanadium and nickel exist in oils as porphyrin complexes. Metalloporphyrins are concentrated in the asphaltene-resinous part of the oil, while the maximum content of vanadium and nickel is accounted for by asphaltenes. Up to the present time, information about features of content and distribution of vanadium, nickel, and the types of the corresponding metal complexes in asphaltenes and resins of heavy oils and natural bitumens has a disparate and non-systemic character. In this work, composition and distribution of vanadyl porphyrins in asphaltenes and resins are studied by the example of heavy oils from the Permian and the Carboniferous productive complexes of the deposits from Volga-Ural oil and gas basin. Isolation of vanadyl porphyrins from oil objects was carried out according to original methods. To concentrate vanadyl porphyrins from asphaltenes a precipitation extraction with a polar solvent was used; vanadyl porphyrins from resins were recovered on a chromatographic column. It was found that the content of vanadyl porphyrins in asphaltenes and resins from heavy oils of the Carboniferous productive complex significantly exceeds the content in the oils of the Permian productive complex. For mass-spectrometric studies obtained concentrates were subjected to additional chromatographic purification using sulfocathionite. Using MALDI TOF spectrometry, homologues of ETIO and DPEP of vanadyl porphyrins in asphaltenes and resins of heavy oil were identified, and their ratio was determined. [ABSTRACT FROM AUTHOR]