Brownfield management opportunities to reduce the back pressure effects on the gas wells

¹ Lucian Blaga University of Sibiu, Faculty of Engineering, 4 E.Cioran, Sibiu, Romania
² Exploration-Production Division, SNGN Romgaz SA, P-ta I.C.Motas 4, Medias, Romania
³ Stimulation-Rehabilitation Production Department, E&P Division, SNGN Romgaz SA, P-ta I.C.Motas 4, Medias, Romania

^* Corresponding author: dan.stefanescu@romgaz.ro

Abstract

Gas mature fields are associated with challenges to optimize the hydrocarbon flow from reservoir to the sales point in a cost effective manner due to declining well productivity. Laslau Mare field is a mature gas field in Transylvanian basin (Mures County) developed in 1970s and is producing∼99% methane with low water-gas ratio. As any brown field, the state of depleted reservoir will generate several constraints for gas flow from formation to surface facilities and further to delivery point. During the exploitation has been observed that the operation conditions are facing with unstable pressure in the system due to low demand. Therefore, the back pressure effect will affect the wells in terms of inability to unload the bottomhole accumulated liquids and the reservoir will suffer a higher pressure drawdown. The best fit-for-purpose solution to overcome the above challenges is represented by installation of group compressor. Laslau Mare field has 3 group compressors running and shows positive results, especially when external pressure fluctuates continuously. This paper explain the challenges seen in 2016 in Laslau Mare field with back pressure effects and how the compression overcome them, and also other solutions that should be considered to optimize the well production.