While continuously reducing of conventional oil resource base in Russia, the interest of large oil companies has been changed to development of hard-to-recover hydrocarbon reserves, in particular, to the Bazhenov formation with significant potential of organic matter. The bedrock is mainly represented by practically impermeable clay-carbonate-silicon rocks, with a significant content of organic matter being separated by low-thickness permeable carbonate-siliceous rocks. An oil being able to recover from carbonate rocks by traditional methods, the primary purpose of the impact on the Bazhenov reservoirs is to involve into development the undrained or low-drained areas of the deposit, and subsequent conversion of solid organic matter (kerogen) into mobile hydrocarbons, which has been confirmed by numerous laboratory and field tests. Researches carried out have shown thermal and gas impact`s most promising EOR technique for application on Bazhenov reservoirs, which consists in pumping air (enriched air, the air / water mixture) in the reservoir and in occurring of high temperature oxidation processes in it with the aim of involving solid organic substances in the development. In addition, the formation rock heated results in improved filtration and capacitive properties as well as formed network of cracks (channels) being for further recovery of mobile hydrocarbons.
Laboratory studies have been carried out in VNIIneft JSC for determination of two essential parameters, which are the amount of mobile hydrocarbons formed from solid organic matter and parameters of chemical reactions under thermal effects on oil and kerogen - containing rock for subsequent thermohydrodynamic modeling. Based on the results of studies for high-temperature oxidation in the "combustion tube", the main technological parameters of the thermal gas treatment are determined with the assessment of data obtained from the field tests for the Bazhenov formation stratum.
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