REDUCTION METHOD OF WATER INFLUX TO WELLS Russian patent published in 2016 - IPC E21B33/138 E21B43/27 

FIELD: oil and gas industry.

SUBSTANCE: reduction method of a water influx to wells involves selection of a production well. A working agent is pumped to the production well. Commissioning of the well is performed. First, laboratory investigations are performed in the centre mark of the considered formation, during which there detected is a possibility of migration of fine clay particles from pores under action of the working agent and blockage of pore channels with them, which is determined by reduction of phase permeability of the reservoir as to water at least by 1.5 times. Water with total salt mineralisation of not more than 5 g/l - low-salt water with density of not more than 1080 kg/m³ is used as a working pumping agent. Pumping of law-salt water on the well is performed with the initial flow rate exceeding maximum historical liquid rate of this well at least by two times. Pumping is performed during at least five days; after that, the well is brought into operation under the same conditions as before pumping. Pumping cycles of law-salt water are repeated at growth of water cut of the well by 10-30% relative to water cut after performance of the previous pumping cycle and extraction of the pumped water. Pumping volume of law-salt water in each next cycle is increased at least by 1.5 times.

EFFECT: improving isolation efficiency of a water influx to wells and increasing an oil recovery coefficient of the deposit.

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