On the example of the Yaraktinskoye oil-gas-condensate field the problem of gypsum scaling under conditions of an abnormally high concentration of calcium ion and sulfate ion, associated with the incompatibility of reservoir and water used for flooding, is considered. The risks of salt precipitation were assessed using mathematical modeling, taking into account the physicochemical properties of mixed waters at different ratios and thermobaric conditions. The study of the component composition of deposits from wells and oilfield communications was carried out using X-ray phase analysis. A forecast of the possible amount of gypsum formed by claster pad of the Yaraktinskoye field was made based on the data on geological modeling of reservoir fluid flows and the composition of produced water as a result of mixing reservoir and injected waters - water of the Litvitsevsky formation, reservoir brine and fresh water. The adaptation of technologies for the removal and prevention of gypsum scaling to the objects of the Yaraktinskoye deposit are shown: two-stage technologies for treating the bottomhole formation zone – alkaline-acid conversion of gypsum deposits, inhibition of gypsumprecipitation in wells, technologies for preliminary discharge of produced water from a well, the ionic composition of which introduces the main incompatibility in flow of produced fluids. Further prospects for the development of technologies to combat gypsum scale for the conditions of the Yaraktinskoye field are outlined.
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