The problem of developing deposits with hard-to-recover oil reserves is becoming more urgent as soon as available deposits with favorable geological and physical conditions are developed; high-tech methods of increasing oil recovery are required, including those associated with the injection of associated gas into oil strata. The methodology for preparing, conducting and interpreting the results of experiments evaluating the efficiency of oil displacement by gas methods differs markedly from the requirements of OST 39-195-86, developed for laboratory determination of the coefficient of oil displacement by water. To obtain qualitative experimental data, it is necessary to take into account the processes of interaction of oil and gas in a porous medium, special requirements to the equipment used, the type of the model of the porous medium is chosen depending on the goals and objectives of the researches, changes are made in the procedure for performing the experiments and processing the results.
Based on many years of experience of VNIIneft JSC carrying out filtration studies of processes of oil displacement by gas and water-gas methods, the principles of physical modeling of gas and water-gas effects on the oil reservoir are formulated:
- the use of recombined models of oils, similar in properties and composition to real reservoir oil;
- maximum correspondence of the parameters of the model gas of recombination (injection) to the characteristics of a real gas;
- choice of the model of a porous medium in accordance with the task of ongoing research;
- minimization of gas leaks during filtration experiments;
- calculation of the displacement coefficient of oil by volume and by mass.
References
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