Experimental and Numerical Evaluation of Water Control and Production Increase in a Tight Gas Formation With Polymer

Abstract

An integrated technique has been developed to experimentally and numerically evaluate water control and production increase in a tight gas formation with polymer. Experimentally, polymer has been appropriately selected and formulated to form a preferentially blocking membrane on the surface of pore and throat in core plugs collected from a tight gas reservoir. The unsteady-state experiments at high temperatures and confining pressures are then conducted to not only measure gas and water relative permeability but also to evaluate the performance of water control and gas production with and without such formulated polymers. The inlet and outlet pressure of the coreholder and flow rates of water and gas are measured throughout the displacement experiments. Theoretically, numerical simulations have been performed to history match the coreflooding experiments and then extended to evaluate well performance in gas fields with and without polymer treatment. Due to the good agreement between the simulated relative permeability and the measured values, the formulated polymer is found to simultaneously control water and increase gas production. Also, it is found from simulation that, after 10 years of production, gas wells after polymer injection show a higher recovery of 10.8% with a lower water-to-gas ratio and a higher formation pressure.