METHOD OF WASHING OVER SAND PLUG IN GAS WELL UNDER CONDITIONS OF LOW RESERVOIR PRESSURE Russian patent published in 2008 - IPC E21B37/00 

FIELD: mining.

SUBSTANCE: method consists in assembling of coiled tubing facility, assembling of blowout preventer, pumping equipment and ejector, lowering flexible tube into well, and preparing of washing foaming fluid. A booster unit and a gas separator are assembled at the well head. After the flexible tube has been lowered, fluid from a pumping station to the booster facility and low pressure gas from a neighbour well or a gas line are being supplied; they are mixed and produce a gas-fluid mixture which is compressed to a value exceeding a reservoir pressure. Then gas-fluid mixture of high pressure is supplied into a gas separator, the mixture is separated into liquid and gaseous phases. Fluid is returned into the booster facility. High pressure gas is supplied to the ejector. Simultaneously foaming fluid from the second pumping station is supplied to the ejector. When a foaming system has been generated in the ejector, it is pumped into an interior cavity of the flexible tube, and washing of the sand plug is performed.

EFFECT: upgraded reliability and efficiency of sand plug removal.

3 dwg