Paper: AN ALTERNATIVE TO CEMENT SQUEEZES FOR WATER AND GAS SHUTOFF APPLICATIONS

This paper presents the development of a new system for water and gas shutoff operations. This system combines a conformance sealant (based on an organically crosslinked polymer) with non-cement particulates. The particulates provide leak off control which leads to shallow matrix penetration of the sealant. This filtrate from the leak off is thermally activated. After exposure to the bottomhole temperature of the well, it forms a three-dimensional gel structure which effectively seals off the targeted interval. The limited and controlled leak off into the matrix during the squeeze results in a controlled depth of invasion. Selective perforation of the oil zones re-establishes the desired hydrocarbon production from the targeted interval. The system can be easily washed out of the wellbore, as compared to cement which must be drilled out. This system can be considered as an alternative to standard cement squeeze operations, casing leak repairs, sealing of thief zones, etc.