Managing Sand Production—The Key to Improved Gas-Well Deliverability and Extended Field Life

Abstract

Summary This paper deals with a case study of a high-rate sour-gas field in Pakistan. The paradigm shift from sand control to sand management boosted production rates by more than 100%. At the same time, higher wellhead pressures and less drawdown will extend field life and ultimate recovery. Major investments such as wellhead or field front-end compression could be delayed and, thereby, appreciable cost savings could be generated. After initial well test results, it was concluded that all wells in the Miano gas field will need gravel-pack installations to protect completion and surface equipment. Only after 2 years of production at high rates in excess of 50 MMscf/D was it found that the installed gravel packs reduce flow rates severely. The paper will demonstrate how, through reinterpretation of data that formed the basis for the previous decision to gravel pack the wells and a thorough evaluation of sand-production potential and risks, a successful sand-management strategy was deployed. Existing gravel packs were perforated, and later production wells have been completed without gravel packs beforehand. Rigorous monitoring of surface equipment by means of erosion probes, ultrasonic wallthickness measurements, and choke-performance charts has been introduced to ensure safe production operations.