TECHNOLOGY OF COMPLETION OF PRODUCING WELLS THAT HAVE OPENED THE SLIGHTLY SATURATED ZONE OF A GAS DEPOSIT

To date, the main share of natural gas produced falls on the Cenomanian productive complex in the north of Western Siberia (Bovanenkovskoye, Medvezhye, Zapolyarnoye, Yamburgskoye, Urengoy deposits). The listed fields have already entered a late stage of development, which is characterized by an intensive decrease in reservoir pressures, production well flow rates, as well as an increase in water occurrences at the bottom of wells as a result of the formation of formation waters. In the Cenomanian gas deposits, four zones of gas saturation are distinguished geologically: the zone of maximum saturation, from which the main production of natural gas is carried out; the zone of undersaturation; the transition zone; the zone of residual saturation. During the opening and development of the last three, a high water content of the extracted products is observed, caused by a two-phase flow of liquid with an advanced movement of the formation waters of the Cenomanian complex. The authors propose a technology for completing gas production wells that have opened the transition zone of the Cenomanian deposit. The technology includes drilling a well for a conductor, lowering a garden column; carrying out cementing work in a backwater space, followed by waiting for cement to harden; drilling a well for an operational column with opening a productive reservoir to its full thickness; lowering an operational column; cementing and waiting for cement to harden; flushing a well with a solution of calcium chloride; drilling a packer; injection of hydrochloric acid into the sub-container space and destruction of fusible inserts; the descent of a drill string with a packer of mechanical action and pushing into the pore structure of a productive formation with a transition zone of a composition based on hydrophobic organosilicon liquids and ethyl esters of orthosilicic acid; the formation of a waterproofing shield in a productive formation with a transition zone, the lower part of which, upon contact of ethyl esters of orthosilicic acid with water, becomes impermeable to water, and the upper part is carried out into the well when it is put into operation, the descent of the downhole equipment. At the end, the well is mastered and put into operation. The proposed technology avoids the problem of the negative effect of the grouting solution on the reservoir properties of the productive formation used in the cementing of the production column, as well as the influence of the perforating fluid during the work on the secondary opening of the productive horizon.