Abstract

Methodologies to predict the optimum End of Tubing (EOT) location with and without artificial lift using steady-state simulation approach are proposed. The optimum EOT location methodology without artificial lift is validated with 2-in. flow loop data and applied to synthetic field-scale cases. This methodology postulates the minimum Δptotal, defined as the difference between toe and wellhead pressure, should determine the optimum EOT location. The methodology is extended to incorporate reservoir coupling and liquid loading analysis to produce a more comprehensive EOT analysis. Liquid loading evaluation is necessary as the optimum EOT methodology may not indicate the liquid loading potential in the well. In the case where reservoir potential is integrated into the methodology, maximizing the well's gas flow rates is used as the optimization criterion. The modification of the methodology to determine the optimum EOT location with installed gas lift or Electrical Submersible Pump (ESP) system is demonstrated. Gas lift can be used to reduce the Δptotal or increase the in-situ gas velocity to avoid liquid loading. In ESP systems, EOT location plays a role in preventing gas lock from occurring in the ESP by utilizing the natural separation of liquid and gas at an appropriate EOT location.

You can access this article if you purchase or spend a download.