Currently, the main residual recoverable reserves in oil fields of Western Siberia, which are under development and planned for commissioning, are concentrated in oil deposits with a complex geological and geological structure, low filtration and reservoir properties, which have a difficult predictable nature of the spatial distribution of reservoir rocks. The main method of intensifying the flow of oil in production wells is hydraulic fracturing, which allows creating highly permeable cracks in low permeable terrigenous pore reservoirs, which leads to the formation of additional difficulties in the development of similar oil deposits with a mixed type of reservoir. The problem with premature watering of produced wells comes to the forefront. The productive deposits of the Tumen formation of the Middle Jurassic age is represented by interstratification of sand-siltstone and clay rocks, often enriched with carbonaceous material, having a complex lithological composition, variable, undeveloped in area and in section. Usualy hydrophobic acid compositions are used at the final stage of development after drilling wells or performing geological and technical measures. The waterproofing by changing the filtration in the pore space is based on a change in the character of the wetting capacity of the enclosing rock, increasing the permeability of oil and reducing the possibility of water movement, during which it is possible to form even more hydrophilic pores.
To change the nature of the wettability of the pore reservoir, various hydrocarbon water-based emulsions with the addition of various stabilization emulsifiers, as well as cationic surface-active agents, are generally applicable.
The results of filtration experiments indicate the high colmatation of the formation ability of various technological fluids during drilling, development and repair of wells, the value of oil permeability in the reservoir is reduced to 6 times from the initial value, when drilling mud is colmatized. The acid hydrophobic composition based on the cationic surfactant and the hydrochloric acid solution is proposed. It has confirmed its effectiveness in terms of restoring the oil phase permeability, by breaking the solid particles of the colmatants with a solution of hydrochloric acid and changing the nature of wettability of the pore space to the hydrophobic cationic surfactant.
References
1. Svalov A.M., Capillary forces effect on the process of a producing well flooding (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2009, no. 10, pp. 64-67.
2. Svalov A.M., Analysis of the factors, determining the efficiency of hydrophobiation of producing wells bottom zones (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2013, no. 3, pp. 74-77.
3. Khisamov R.S., Vysokoeffektivnye tekhnologii osvoeniya neftyanykh mestorozhdeniy (Highly efficient technology of development of oil field), Moscow: Nedra Publ., 2004, 628 p.
4. Akhmetshin M.A., Povyshenie proizvoditel'nosti neftyanykh skvazhin obrabotkoy prizaboynoy zony rastvorami poverkhnostno-aktivnykh veshchestv (Improving the the productivity of oil wells by bottomhole treatment with surfactants solutions): thesis of candidate of technical science, Ufa, 1968.
5. Akhmetshin M.A., On artificial hydrophobization of rocks of bottomhole zone of oil wells (In Russ.), Neftyanoe khozyaystvo= Oil Industry, 2016, no. 1, pp. 73-77.
