Reducing CO2 Emissions During Wellbore Cleanout Operations by Employing Coiled Tubing Fluid Oscillation Tool – A Case Study

Abstract

Abstract During 2022, oil and gas operations resulted in emission of 5.1 billion tons of CO2equivalent. These emissions must be reduced on the journey towards net zero emission. Wellbore cleanout operations with coiled tubing are one of the most frequent operations performed during the life of a wellbore. The coiled tubing and associated equipment used for wellbore cleanout operations is powered by diesel engines which result in high CO2 emission during operation. However, these emissions can be reduced by using a fluid oscillation tool. A fluid oscillation tool converts kinetic energy of the pumped fluid into potential energy resulting in the creation of pulsating waves. These pulsating waves induce cyclic stress in the scale. Continuous cyclic stress induces fatigue failure in the scale which ultimately leads to disintegration of the scale present in the wellbore or critical matrix. Fluid oscillation tools can remove scales in less time and provide better fluid velocities in the wellbore even in nitrified treatments. This ultimately reduces the time of operation considerably. Furthermore, reduction in operational time corresponds to low consumption of diesel by the CT and associated equipment, leading to lesser emission of CO2. A fluid oscillation tool was employed at multiple wells in the region of this case study to perform wellbore cleanout jobs. This paper thoroughly performs data analysis of four different wells and demonstrates the impact of fluid oscillation tool on different performance factors. Using a fluid oscillation tool led to a decrease in CO2 emission between 35-62%, reduced CAPEX between20-47% and increased production between 170-310%. Nearly 57% of the well intervention operations performed in the region of this case study are wellbore cleanout operations. Replacing the conventional jetting tool with a fluid oscillation tool led to a decrease in CO2 emission from 1843 Tons to 924 Tons. This reduction corresponds to approximately 50% of CO2 emission during wellbore cleanout operations. The scale of this reduction would be more appreciable when adopted universally.