Simulation of Fracturing-Induced Formation Damage and Gas Production From Fractured Wells in Tight Gas Reservoirs

Fracturing fluid may jeopardize the production of hydraulically fractured tight gas formations. Because capillary forces act stronger in low-permeability formations, the invaded fracturing fluid is harder to remove. The increase of water saturation around the fractured well affects the mobility of the gas phase, particularly in tight formations where the gas relative permeability declines strongly when water saturation increases. This damage might greatly reduce the gas production in a very long cleanup period. This paper presents numerical simulation techniques to account for formation damage with both a near-well model and a full-field model for fractured wells in tight formations. For the full-field model, the skin determined from an inversion is suitable for long-term production simulations, and a sector model can be used to update the well skin through a coupled modeling so that the full-field model can be used correctly over the whole life of the project.