Water production or cross flow during production phase is highly undesirable as it incurs additional costs of water handling at surface and reduces relative permeability of hydrocarbons to flow. Problems associated with water production or its cross flow escalate in depleted and HT wells limiting water shut-off options. Long-term zonal isolation to prevent unwanted fluids and cross flow is challenging in such wells due to the need of proper placement in the targeted zone, compatibility of fluid/tool with the downhole temperature and its sustainability. The use of mechanical plugs including packing elements have limitation of application in some instances due to high temperature and odd sized tubulars.

Having the abovesaid limitations, an engineering solution was made by testing and implementing reinforced Polymer Gel (a polymer-based gel loaded with silica sand) providing right angle set properties upon exposure to the given temperatures. The aforesaid combination produces a rigid, robust gel structure ideal for shutoff treatments into fractured, vugular and high permeability formations. Such gels can penetrate deep into the matrix or small fissures where the mechanical packers cannot reach to shut off the excess water.

This paper demonstrates the assessments to counter above challenges and application of re-enforced temperature activated anionic polymer for water shut off in candidate wells in Southern & Northern regions of Pakistan.

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