METHOD FOR EFFECTIVE DEVELOPMENT OF GAS DEPOSITS IN LOW-PERMEABLE ROCKS Russian patent published in 2014 - IPC E21B43/16 E21B43/26 

FIELD: oil and gas industry.

SUBSTANCE: at the deposit vertical and horizontal wells are drilled, including multilateral wells, and the gas deposit is impacted through them by means of hydraulic fracturing of low-permeable rocks. According to the invention a vertical well is drilled at the gas deposit and vertical and horizontal wells are drilled in the circumferential direction from its bottomhole navigationally thus uniting them into a common system connected hydraulically. Thereafter the stage of gas inflow stimulation is provided to uncased horizontal boreholes in the deposit. To this end water is injected to the peripheral vertical and horizontal wells with water drainage to the vertical well. This well is covered, pressure in the horizontal boreholes is increased up to the value exceeding the rock pressure in the overlying rocks at this depth. Then high-pressure air is injected into the vertical and horizontal wells and the vertical well is open to the atmosphere. Pressure in the horizontal boreholes is reduced from the maximum value up to the minimum value of 0.1-0.2 MPa. The deposit is subject to similar pneudraulic pulsed impact through the horizontal boreholes repeatedly thus stimulating opening of microscopic pores and cracks in the deposit zones adjacent to the horizontal boreholes and in result inflow of natural gas to new artificial collectors.

EFFECT: creating a new efficient and environmentally friendly technology for gas deposits development in low-permeable rocks - sandstones.

7 cl, 1 ex, 3 dwg