Abstract
The following paper will detail the use of a high angle electric submersible pump (ESP) tangent in Northern Oklahoma Horizontal Oil and Gas Wells to maximize ESP drawdown at the sandface by enhancing gas separation at the ESP intake.
ESP performance expectations in horizontal wells can be severely diminished due to gas interference which can cause rapid head degradation in the ESP system. Understanding how the gravitational effects on the fluid stream can alter flow patterns in a horizontal wellbore is paramount to achieving the most cost effective solution for avoiding gas at the ESP intake while maximizing drawdown. Failure to consider how changes in wellbore deviation may alter fluid flow in deviated ESP operations before a well is drilled and completed may result in a completion design where the ultimate hydrocarbon recovery is partially inhibited due to gas interference.
Results detailed from Northern Oklahoma Horizontal Oil and Gas Wells indicate that the use of a high angle pump tangent in ESP operations was able to help accomplish greater than 90% gas separation at the intake of an ESP at bottom hole pressures less than 100 psia and gas-to-liquid ratios in excess of 2000 scf/bbl.
The application of advanced horizontal well technology has increased the demand for cost effective and reliable ESP solutions which mitigate the negative economic effects of prolonged downtime and repair costs associated with the challenges of operating in the modern horizontal wellbore environment. Conventional ESP design methodology for effective gas avoidance and deliquification in the vertical wellbore environment does not address the changes in multi-phase fluid behavior and flow patterns that are encountered as the wellbore is deviated in excess of 85 degrees from vertical.
