The article discusses the theoretical foundations, world experience, as well as the key results of laboratory studies of the enzyme composition used to stimulate oil production and as a enhanced oil recovery method. Currently, there are some of the problems at fields with low temperature, high oil viscosity and high reservoir properties such as the impossibility to create a high drawdown on the reservoir (in conditions of shallow reservoirs), the migration of reservoir particles and, as a result, clogging of the liner filter, which in turn causes decrease in production rate for many wells, especially for sand-bearing wells working for objects with high-viscosity oil. The formation of a filter cake on the filter part of the liner consisting of a mixture of high-viscosity oil and sandstone particles, as well as the low phase permeability for oil of a hydrophobic reservoir, can partially or completely block the flow of fluid into the well and act as a local skin factor in the bottomhole formation zone. The solution to this problem can be methods that reduce the viscosity of oil: thermal and chemical, one of which is the use of an enzyme composition to destroy high-molecular compounds of hydrocarbons and to change the wettability of the reservoir to hydrophilic. To confirm these effects, laboratory filtration studies were carried out on core from the Vostochno-Messoyakhskoye field. Two groups of tests were carried out with enzyme concentrations of 2.5 and 10%, respectively, as a result, an increase in displacement ratio from 2.4 to 6.9% (depending on the concentration of the solution) was obtained and the recovery of phase permeability after enzyme filtration was 15% greater, than after water filtration.
References
1. Rahayyem M., Mostaghimi P., Alzahid Y.A. et al., Enzyme enhanced oil recovery EEOR: A microfluidics approach, SPE-195116-MS, 2019, DOI:10.2118/195116-MS
2. Tarang J., Dehradun A.S., New frontiers in EOR methodologies by application of enzymes, SPE-154690-MS, 2012, DOI: https://doi.org/10.2118/154690-MS
3. Liu He, Zhang Zhonghong, Biology enzyme EOR for low permeability reservoirs, SPE-144281-MS, 2011, DOI: https://doi.org/10.2118/144281-MS
4. Mukhametshin V.V., Shchetnikov V.I., Velieva O.V., Study of the efficiency of using enzyme solutions on oil reservoir models (In Russ.), Bashkirskiy khimicheskiy zhurnal, 2020, V. 27, no. 2, pp. 74–78, DOI: 10.17122/bcj-2020-3-74-76
5. Ott W.K., Thu Nyo, Win Nyunt Aung, Aung Thet Khaing, EEOR success in Mann Field, Myanmar, SPE-144231-MS, 2011, DOI: https://doi.org/10.2118/144231-MS
