Paper presents the case study of diverter injection at Kharyaginskoye field. Main development target is Devonian carbonate reservoir. In horizontal plane, the reservoir is divided into two zones: barrier reef and lagoon area. Zones differ by permeability distribution and fluids flow behavior. Core analysis is shown the presents of second porosity system, however, the hydrodynamic survey doesn’t indicate double porosity system in the reservoir. The reservoir is saturated by the light oil (1.15 mPa⋅s). Formation water salinity is relatively high (170000 ppm). The waterflood process is implementing. The production watercut is about 60%. Reservoir temperature is 61 °C, it makes possible to inject a variety of diverters. As screening result cross-linked acrylamide polymer with addition of chromium acetate (cross-linking agent) was selected as the most efficient injection agent (diverter). Injection was performed in 5 injector wells; the production rates of 16 producers were monitored. The incremental recovery after 7 months after diverter injection is about 20000 tons and still increasing.
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