The 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 well head pressures and lesser drawdowns will extend field life and ultimate recovery. Major investments like well head - or front end compression could be delayed and thereby appreciable cost savings are generated.
After initial well test results it was concluded that all wells in the Miano gas field will need gravel pack installations in order to protect completion and surface equipment. Only after two years of production it was found that the installed gravel packs reduce flow rates severely. The paper will demonstrate how, through re-interpretation of data which were basis for the previous decision to gravel pack the wells and thorough evaluation of sand production limits and risks, a highly successful sand management strategy was deployed. Existing gravel packs were perforated and later in-field wells have been completed without gravel packs beforehand. A rigorous monitoring of surface equipments by means of erosion probes, ultra sonic wall thickness measurements and choke performance charts has been introduced in order to ensure safe production operations.
The paper presents a case study of a sour gas field in Pakistan. From drill stem tests on exploratory and appraisal wells it was gauged that sand production will prevail during field production. In consequence a sand control strategy was formulated on the basis of complete sand exclusion since zero sand production tolerance was believed to be mandatory in high rate gas wells. To achieve this goal all wells have been completed with gravel packs inside the 7" liners. These gravel packs consisted of 2 joints of 4 ½" wire wrapped screens, either 12 or 20 gauge slot width based on sand size analysis from produced sand samples packed with 20/40 mesh and 12/20 mesh gravel sand respectively.
