Reactivation Project

Abstract The reactivation project is a selection process to assess the value of inactive wells for the purpose of qualifying them or not as reactivation candidates. Engineering and economic criteria are incorporated into the selection process. The inactive wells studied belong to mature hydrocarbon fields located in West Texas. Primary field development dates to the early 20th century. Since then, infill drilling and various enhanced-oil recovery projects have been performed. Identification of reactivation candidates is important to realize the full potential of mature producing fields and to recover potentially bypassed pay. From a data set of 200 wells two reactivation candidates (wells A and B) were selected. The purpose of the paper will describe the selection process and focus on the well reactivation. Several factors limit the recovery ratio from a given well. As the global demand for energy grows, petroleum companies will focus on the exploration and production of new hydrocarbon reserves. In the process of shifting resources from existing to newly-found fields, companies may neglect to realize the full potential of mature fields. Furthermore, engineering practices and tools of the past contribute to undermining recoverable reserves from a given reservoir. Advances in technology have led to improved field development strategies and optimum well recovery. Reactivation project applies current technologies for identifying and unlocking potential in inactive wells. Based on the reactivation study, both wells A and B promise to increase reserves and add value. Well A is estimated to add recoverable reserves of 37 thousand bbl of oil and 372 MMcf of gas. Moreover, there is a contingency plan for well A. If reactivation of the lower zone is prevented by a major casing failure, then a shallow recompletion is proposed. The shallow zone is estimated to hold 534 MMcf of recoverable gas. On the other hand, well B evaluation indicates recoverable reserves of 30 thousand bbl oil and 89 MMcf gas. The two reactivations have a maximum potential of 145 thousand BOE and an associated net present value (NPV) of $1.92 million (reserve and NPV values do not include well A contingency plan).