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Deliquification of Thrace Basin gas wells
- Publisher: European Association of Geoscientists & Engineers
- Source: Conference Proceedings, 19th International Petroleum and Natural Gas Congress and Exhibition of Turkey, May 2013, cp-380-00050
Abstract
The Thrace basin is located in the European section of NW Turkey. It consists mainly of shallow gas production with a depth of 500 to 1500 meters. These wells exhibit a rapid production decline as rates drop off sharply within the first few months of production. Left unassisted, the production of these wells drops off to unacceptable levels quickly due primarily to liquid loading. In 2012 a project was undertaken to address the liquid loading problem. Candidate wells were selected from the Osmancik, Mezardere, and Teslimkoy formations with the intent of installing plunger lift systems for deliquification. Of the target wells, some had been frac’d and others had not. The expectation was that the fracturing would open up production and that the plunger lift would allow these wells to stay ahead of the liquids. Various types of plungers were used in both continuous flow and conventional plunger lift modes. Automated control options were utilized for auto-optimization and gathering of information via telemetry. The results of the first group of wells showed mixed results. Some showed significant production increases while others merely maintained the production levels and slowed down the production decline. On those wells where the plungers were installed during the steep portion of the decline, the rates continued to drop even after installing artificial lift. An investigation as to the similarities of those showing the best results was done to help identify successful future candidates. Frac sand created an additional problem on several of the wells. Even though the volume of sand had a tendency to decrease after some flow back time, there was still enough sand in some wells to not make plunger lift a viable option. All in all the production was increased significantly. The intent of this paper is to evaluate these wells and help identify further candidates and production results.