Production decline rate slowing-sown and enhanced recovery of residual reserves demand application of new technologies. The preferred technologies are those that do not require significant capital costs. Methods changing reservoir filtration flows using thickening and gelling compositions – flow diverting technologies – fall into this group. When choosing a diverter composition and a method, factors like geological-and-physical conditions, current development status, water pathway after water injection and performance efficiency are considered. The paper discusses the results of the technology development and project implementation on water breakthough isolation using cross-linked polymer systems on horizontal wells of Vankorskoye field, taking into account the water production mechanism in producing wells. Based on a complex analysis, which includes identifying geological-and-physical structural characteristics and current development status of the deposit, and taking into account well and tracer tests it was found that the main watering source of producing wells is water injected though the water injection network. The authors found that the injected water percolates in sequence along the fractures in the bottom-hole zone of injection wells, and further the filtration goes on to the highly-permeable watered matrix and to production wells. Taking into account the identified water pathway, the strategy of placing the water-isolating polymer gel was developed. Based on laboratory tests the authors have selected reagents and solutions of the gel-polymer composition with optimum properties. The technology has been field-tested and has shown high process performance.
References
1. Ismagilov T.A., Application of water control technologies, considering the mechanisms of injected water breakthrough (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2015, no. 11, pp. 56–59.
2. Magzyanov I.R., Ismagilov T.A., Zakharov V.P. et al., Realization of new method of gel placement in watered high permeable formations (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2011, no. 6, pp. 25–29.
3. Ismagilov T.A., Magzyanov I.R., Water shut-off technology for injection wells treatment in heterogeneous systems with crossflows (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2013, no. 11, pp. 54–57.
4. Zakharov V.P., Ismagilov T.A., Antonov A.M. et al., Waterproofing of cracks from the side of injection wells in carbonate reservoirs (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2010, no. 12, pp. 102–105.
5. Zakharov V.P., Ismagilov T.A., Asmandiyarov R.N., New methods of filtration flows adjustment in low permeability reservoirs with water shutoff (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2012, no. 1, pp. 54–57.