METHOD FOR DEEP OIL WELL BOTTOM AREA CLEANING Russian patent published in 2005 - IPC

FIELD: oil industry, particularly oil production stimulation to recover reservoir properties of bottomhole formation zone by gas-and-liquid mixture forcing into and following removal from bottomhole formation zone.

SUBSTANCE: method involves generating fine gas-and-liquid mixture circulation the well, wherein the fine gas-and-liquid mixture is obtained by forcing mixture phases through head disperser, along with increasing stepped gas content in the mixture; circulating the mixture up to sealant removal termination. The fine gas-and-liquid mixture circulation is initiated by supplying gas-and-liquid mixture to flow string when discharge line valve is opened. After stable gas-and-liquid mixture circulation reaching the discharge line valve is closed and fine gas-and-liquid mixture is injected into bottomhole formation zone. Then the discharge line valve is opened and the circulation is restored and maintained up to termination of sealant removal from bottomhole formation zone.

EFFECT: possibility of deep bottomhole formation zone cleaning due to increased differential pressure and, as a result, increased efficiency of sealant removal.

3 cl, 2 ex, 1 dwg