How to Evaluate and Predict the Deliverability Change of Gas Condensate Wells

Condensate liquids retrograde below the dew point pressure and diminish gas relative permeability and thus reduce the deliverability of gas condensate wells. The deliverability varies due to the changes of gas effective permeability and other parameters; however, the present deliverability testing methods were not applicable to gas condensate wells because those methods were all based on the assumption that the formation properties such as permeability and fluid properties were constant. A new testing method for gas condensate wells is proposed in this work, by which the variable coefficient deliverability equation can be obtained. Case study shows that the variable coefficient deliverability equation obtained from the proposed deliverability testing method can represent changes of formation properties and fluid properties, thus the deliverability of gas condensate wells can be accurately evaluated and predicted by this testing method.