METHOD FOR DEVELOPING WELL AFTER HYDRAULIC FRACTURING Russian patent published in 2017 - IPC E21B43/25 E21B43/16 

FIELD: oil and gas industry.

SUBSTANCE: method of well development includes lowering a tubing string into the well, binding a nitrogen compressor with an injection line with the upper end of the tubing string at the wellhead, injection of nitrogen through the tubing string into the well, circulation of aerated liquid into a channel-type container. At that, the tubing string is equipped with a packer at the wellhead and lowered into the well. The packer in seated on the well above formation cap. Hydraulic fracturing of the formation is produced to form a fracture crack and its fixation by proppant. Then the lower end of the coiled tubing string (CT) is provided with a flushing nib and check valve at the wellhead. The CT string is lowered into the well by 100 m and the pump set is started at a flow rate of 3.0⋅10^-3 m³/c. Circulation of process fluid is induced through annular space between the tubing and CT strings in the channel-type container. Next, the CT string is lowered to the lower end of the tubing string. Compressor is started with nitrogen flow rate of 0.2⋅10^-3 m³/s and circulation of aerated liquid is induced along inter-tube space between columns of tubing and CT into channel-type container. The CT string is lowered to the bottomhole. The well bottom is flushed with aerated liquid to clean water for 2 hours, after which the pump unit and compressor are switched off. The CT string is lifted in the tubing string 20 m above the lower end of the tubing. The nitrogen compressor is started. After the release of nitrogen from inter-tube space between the tubing and CT strings into the channel-type container, the well is developed with nitrogen at a flow rate of 16 m³/min for 2 hours. In the course of well development, the CT string is lifted and lowered every 20 minutes at a rate of 5 m/min. In the process of development, sampling fluid is sampled every 30 min on oil-water percentage, average flow, sampled water density. After 2 hours, the compressor is stopped and process settling is carried out for 2 hours, then CT string is introduced into the well to the bottom without circulation at a rate of 2 m/min with unloading of CT string on the bottom with a force of 5000 N.

EFFECT: increase of efficiency and quality of well development, simplification of technological process.

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