INVESTIGATION OF THE SALT FORMATION ISSUE IN THE OIL FIELD OF THE PRECASPIAN REGION

Abstract

This article analyzes complex laboratory and simulation studies of salt deposition during oil production in conditions of low permeability with falling reservoir pressure. The object of research is Jurassic deposits of horizons with a depth of up to 3000 m. The study of salt formation problems pursues the following objectives: to determine the type of salts (within and using the resources available for research), to conduct modeling to understand longterm trends in salt formation (during water injection projects) or short-term trends (during hydraulic fracturing or cattle), as well as to make recommendations based on tests and the Schlumberger database. The formation waters of the Jurassic deposition of the field have similar hydrochemical parameters along the horizons and are chlorocalcium brines, the total mineralization of which ranges from 147.1 g/l to 186.6 g/l. According to the available data, there is no clear dependence of mineralization on the depth of occurrence. The density in surface conditions is 1097-1131 kg/m3. In terms of concentration, chlorides predominate over alkali metals (sodium, potassium), and the waters are also noticeably enriched with calcium, the content of which significantly prevails over magnesium. A characteristic feature is the low content of sulfate and bicarbonate ions. The research and scientific nature of this work is confirmed by the fact that a new scientific software for the analysis of salt deposition was used for the Kazakhstani industry of intensification of hydrocarbon production. Modeling of critical thermobaric points covers the range of predicted parameters of reservoir pressure and temperature, as well as the resulting temperature in the bottomhole zone, taking into account the operation of the installation of an electric centrifugal pump. The sensitivity analysis was carried out taking into account the percentage ratio of injected and reservoir water, the parameters of the water used during hydraulic fracturing were calculated separately. The result of the study is a quantitative assessment of the permeability from salt deposition and preventive measures to preserve the productivity coefficient of wells.