The problem of developing deposits with heavy and highly viscous oil, whose global reserves are estimated at 1 trillion tons, special attention has recently been given. In the development of such oil deposits, thermal methods of increasing oil recovery are widely used, in particular, steam and thermal effects on formations. As a rule, for a preliminary assessment of the applicability of a particular technology, in the laboratory, special filtration studies are carried out on core samples that mimic the processes occurring in the reservoir. In this article, a highly viscous bituminous oil deposit (viscosity is 35500 mPa⋅s, density is 1021 kg/m3) with an initial reservoir pressure of 6.8 MPa and a vaporization temperature of 280°C is selected as the object of heat and steam exposure. Under these conditions, the use of a standard core holder providing a maximum temperature of 180°C is not possible.
VNIIneft JSC developed a methodology and laboratory setup for the physical simulation of oil displacement as a result of steam injection at high temperatures. Unlike a traditional core holder, in which a cylindrical core sample is densified by compressing a plastic cuff with liquid pressure, in the proposed method, the core is mounted inside a special high-temperature filtration model designed specifically for experiments with high-temperature steam displacement using a sealing material that can withstand a given temperature. A series of test experiments confirmed that during heating due to thermal expansion, a reliable compaction of the core sample occurs inside the model, which completely prevents the possibility of slipping of the displacing agent along the edge of the sample or model wall.
References
1. Antoniadi D.G., Valuyskiy A.A., Garushev A.R., The state of oil production by EOR in the total world production (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 1999, no. 1, pp. 16–23.
2. Khisamov R.S., Analysis of efficiency of steam-gravity recovery technology for development of heavy oil reserves (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2014, no. 7, pp. 24–27.
