METHOD OF SAND PLUG WASHING UP AND PREVENTION OF SAND ADDITION IN WATERING WELL Russian patent published in 2008 - IPC E21B37/00 

FIELD: oil and gas industry.

SUBSTANCE: invention refers to oil and gas producing industry, particularly to sand plug washing up and to prevention of sand addition. The method consists in assembling coltubing (coiled tubing) device, in installing a blow out preventor and pumping equipment, in preparing wash foam liquid, in washing of well in the zone of sand plug formation to the lower apertures of the perforation interval, in determining gas-water contact by means of geophysical methods, and in pumping water insulating composition into the perforation interval, said composition can, for example be made on base of polyvinyl alcohol creating a water insulating screen displacing water from a bottomhole inside the reservoir along radius. Then pressurising composition, for example polyacrylamide resin, is pumped. When pressurising composition has hardened, near well zone of the horizon is treated with, for example a foam-acid composition, and development of the well commences.

EFFECT: upgraded efficiency of plug removal under conditions of low reservoir pressure, elimination of causes of sand occurring.

5 dwg