Gas Lift-Jet Pump Hybrid Completion Reduces Nonproductive Time During Unconventional Well Production


Authors

O. A. Nunez Pino (Weatherford International Inc.) | T. S. Pugh (Weatherford International Inc.) | J. Hubbard (Weatherford International Inc.)

Publisher

SPE - Society of Petroleum Engineers

Publication Date

June 1, 2016

Source

SPE Argentina Exploration and Production of Unconventional Resources Symposium, 1-3 June, Buenos Aires, Argentina

Paper ID

SPE-180958-MS


Abstract

Gas lift is a preferred lifting method to produce unconventional wells across the world. During specific stages of the well life, however, it might happen that water percentage raises enough to make the tubing flow gradient too high for lifting with the maximum operating pressure and rate of injection gas. This results in unplanned nonproductive time. A slickline-deployable jet pump can be a cost-effective alternative to effectively unload the well and resume production with gas lift.

The addition of a sliding sleeve door (SSD) to the tubing string, installed between the deepest gas lift mandrel and the annular packer, will allow the deployment of a slickline-set jet pump. The backup jet pump provides a valuable and cost-effective alternative in three potential scenarios: when unloading fracking fluids before beginning gas-lift production, when restoring production after an unpredicted shutdown of the gas-lift compression system, and when the producing water cut becomes higher than expected.

An operator in Logan County, Oklahoma, installed the gas lift-jet pump hybrid completion in five wells. The completion was basically designed for gas lift with a standard "X" profile SSD installed between the packer and the operating gas-lift valve. The dual-purpose tubing string was installed in each well in one trip. To produce fracking fluids left in the wellbore, standard-flow jet pumps were set in the SSD, mobile hydraulic-lift surface units were hooked up to the Christmas tree and jet pump production operation started. On average, fracking water was produced 66% faster than by swabbing and rod pumping, and 33% faster than with nitrogen lift. Upon recovery of the fracking fluids, the wells were producing enough gas to successfully start the gas lift systems in approximately 6 days.

This simple but ingenious dual-purpose completion approach has already proved to solve the problem of unconventional well production load-up during the early production stage of gas lifted systems. The information provided in this paper will help operators plan, design, deploy, and operate a dual-purpose gas lift-jet pump well completion.