Stimulation Treatment Design and Evaluation of Old Producing Wells

The productivity of many old producing wells can be increased by the use of a properly designed stimulation treatment. The majority of these wells, both pumping and nonpumping, are fractured. Partial healing of the hydraulic fracture may occur as pressure declines in the reservoir. In addition, other common forms of formation damage occur with time. An accurate evaluation of the existing conditions in the well is required for proper design of the stimulation treatment. In this paper, an attempt has been made to utilize production data and pressure transient test data simultaneously to evaluate the existing condition of the well. The use of published type-curve techniques for unfractured, fractured and decline curve analyses has been emphasized to eliminate ambiguities and to arrive at a reliable conclusion. Both conventional pressure data and liquid-level measurement data have been used in this study. A two-dimensional simulator has also been used to aid stimulation treatment design and performance evaluation.