WELL SILENCING TECHNOLOGIES IN CONDITIONS OF MULTIPLE COMPLICATIONS

Abstract

Silencing of wells in the conditions of the Jurassic facilities developed by «Kharampurneftegaz» LLC is complicated by a number of negative factors, such as low permeability of the hydrophilic reservoir collector, high gas factor, low reservoir pressure, which significantly reduce the success of underground repair of wells (URW). To eliminate the influence of these complications in URW, an approach to silencing technology has been developed, which consists in combining several types of technological fluids, which, when used together, can eliminate the risks of reducing the production potential of wells after repair. So, to prevent gas manifestations during the URW, a blocking liquid based on the polymer «Biopol» and surfactant (gas-blocking compound, GasoBC) has been developed, acting due to its viscoelastic properties (polymer) and foaming ability in contact with gas (surfactant). A buffer liquid designed to prevent swelling of clay cement, reduce interfacial tension and restore phase permeability in oil was developed on the basis of a 6% HCl solution with the addition of a surfactanthydrophobizer (buffer hydrochloric acid liquid, BufHA). Blocking silencing compound (BSС) based on a Biopol polymer solution with a suspended suspension of microcalcite (BSС-microcalcite) and halite (BSС-halite) allows to prevent the absorption of silencing fluid at reduced reservoir pressure in wells with hydraulic fracturing. Pilot field testing of the technology of silencing wells with multiple complications was carried out at 23 wells, where GasoBС block packs were used 21 times, BufHA — 9 times, BSC-halite and BSC-microcalcite — 14 and 9 times, respectively. 8 typical silencing plans have been compiled for various parameters of wells. The results of research and development works are fixed in the Instructions of  «Kharampurneftegaz» LLC  on the topic «Selection of blocking silencing compounds during well repair».