A fully coupled dual-porosity model is developed and used to simulate a given field condition. History match from ten wells in Northwest China shows a significant and sustained production decline, despite a continuous increase in drawdown. A critical drawdown is identified, after which the drawdown increase effect is neutralized from that from the permeability reduction. A different drawdown increase strategy by maintaining a constant bottom hole pressure (BHP), yet increasing the far-field reservoir pressure is proposed and applied. This way the drawdown can be increased without reducing the near wellbore permeability. Production decline can be stopped and reversed. Simulations on the field indicate that more than 30% production rate increase can be expected from each well, depending on the in-situ stress level against the permeability changes in the formation. Identifying these critical drawdowns is also economically important, as ineffective drawdown increase can generate zero or negative incremental production, at extra cost.
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