Vankor oil and gas condensate field is one of the largest in the oil and gas region of the Nadym-PUR-Taz basin of Western Siberia. Development of the field began in 2009 and is carried out by a system of horizontal wells, with a horizontal section length of up to 1100 m. directional wells. To maintain high rates of field development, the issue of restoration and increase of productivity of horizontal wells becomes relevant. One of the effective methods to restore the productivity of wells is the treatment of the bottom-hole zone with composite compositions including solvents and acids. This article discusses the method of selection of technologies and reagents to restore the productivity of horizontal wells on the example of the Vankor field. The methodology for the selection of technologies and compositions consists of the following steps: study of acid compositions; exploration of changes in the filtration characteristics of an oil-saturated porous medium (cores) when exposed to an acid composition; selection of the target reagent; compatibility of bottom-hole formation zone treatment reagents with reservoir fluids; consumption rate of reagents for carrying out bottom-hole formation zone treatment; the time required to remove (destroy, dissolve) the colmatant; a method for the delivery of a reagent to the place of sediment colmatant; products formed when reagents act on colmatant; removal of reaction products from the well; risks of incompatibility of reagents with each other and with formation fluids; materials and technology for selective processing of a given interval. The proposed methodology for the selection of bottom-hole formation zone treatment technology in horizontal wells was tested at the VNGKM. 20 well treatments were carried out on the main reservoirs, the specific consumption of reagents varied from 6 dm3/m to 32 dm3/m. The main results: the minimum increase in oil production was 11 tons/day, the average increase in oil production was 24 tons/day; there were no complications during the operation of wells after the bottom-hole formation zone treatment; the duration of the effect depends on the specific consumption of reagents, a stable effect is obtained for a specific consumption of more than 8 dm3/m. The results of the treatments confirmed the effectiveness of the proposed methodology. Based on the results of the field work, it was decided to introduce the proposed bottom-hole formation zone treatment technologies at the Vankor field.
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