In recent years the task of development for an unconventional oil deposits (like a shale oil, heavy oil sands, tight oil, etc.) became highly important. On of such task is the development of Bazhenov formation reservoir containing large amounts of kerogen. Application of a thermal and gas impact (TGI) considering as an effective solution to this problem by pumping air under high pressure into the producing formation leading to the emergence of a highly miscible with the oil displacing agent that is formed by in-situ oxidation and thermodynamic processes. A thermal gas impact by pumping air under the high pressure into the producing formation is considered as an effective solution of this problem causing the moving hearth of burning due to in-situ oxidation and thermodynamic process. In the anoxic zone of the coking area ahead of the combustion front, which is characterized by increased temperatures, the kerogen is exposed to low temperature pyrolysis.
To determine the optimal conditions for forming the maximum amount of liquid hydrocarbons due to pyrolysis reaction of solid organic a series of experimental studies of the pyrolysis kerogen-containing rocks in thermochemical reactors for the Bazhenov formation had been carried out in VNIIneft JSC. Besides, for the qualitative evaluation of the obtained liquid phase from the kerogen a complex study for determination the heat release in differential scanning calorimeter (DSC1) had been carried out. As a result of these studies it has been shown that the possibility of separating the organic matter of the Bazhenov formation from its mineral composition by using low temperature pyrolysis (350-450°C) with formation of liquid hydrocarbons observing in the whole studied temperature range and it`s reduction with increasing duration of the experiment as a result of further destruction. Comparison of the dissipation curves for the rock samples before and after experiments in the thermo-chemical reactor shows the number of additionally obtained liquid phase due to the pyrolysis of kerogen. Based on the results of the studies a light hydrocarbon components are mainly occurring at temperatures of 350-400°C. It should be noted that while the temperature reaching 400°C and above a secondary-cracking processes are overlaying with pyrolysis with a formed thermo-bitumen initiating to decompose into volatile components and coke which may cause clogging of the pores and channels in the rock.
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