Productivity Index Enhancement of Stimulated Gas Wells through Hydraulic Fracturing

Abstract

Well stimulation may be required for reservoirs that are not performing optimally. The justification for stimulation is always an economic justification, where the increased productivity or injectivity is weighted against the cost of the treatment. With the creation or restoration of hydraulic fractures as stimulation technique, the surface area of the formation exposed to the borehole is increased and the fracture provides a conductive path connecting the now-freed gas to the well. Therefore, hydraulic fracturing is one of the most widely used and accepted methods for enhancing well performance. The analysis of hydraulic fracturing data from a hydraulically fractured vertical gas well in a low-permeability sandstone reservoir and the evaluation of the effective fracture parameters, such as fracture half-length, fracture conductivity, and reservoir properties, were discussed using actual vertical fractured gas wells. The author discusses the application of hydraulic fracturing in a tight gas reservoir, and demonstrates how a significant increase in gas productivity from a tight gas field was attained with a very high propped fracture treatment success rate. The author also details how the correct design of fracture treatments can enhance tight reservoir recovery rates, and fully utilize vertical wells as a low cost. Field examples illustrate a case field study analysis and show that the importance of this analysis is supreme for the owner companies trying to optimize high-value hydraulic fracture treatments.