What is the best way to optimize well control for carbon capture and storage wells?

3 Drilling fluids and mud weight

Another important factor that influences well control is the selection and management of drilling fluids and mud weight. Drilling fluids are used to lubricate, cool, and clean the drill bit and to transport the cuttings to the surface. Mud weight is the density of the drilling fluid, which determines the pressure exerted by the fluid on the formation. For CCS wells, drilling fluids and mud weight need to be carefully chosen and adjusted to match the formation pressure and to avoid fracturing or collapsing the formation. Furthermore, drilling fluids need to be compatible with CO2 and resistant to corrosion and degradation.

4 Blowout preventer and wellhead

A blowout preventer (BOP) is a device that seals the wellbore in case of a sudden increase in pressure or flow of fluids, such as gas or CO2, that could cause a blowout. A wellhead is a structure that connects the BOP to the surface equipment and provides access to the wellbore. For CCS wells, a BOP and a wellhead are essential components of well control that need to be designed and installed properly to handle the high pressures and volumes of CO2 injection. Moreover, a BOP and a wellhead need to be regularly tested and maintained to ensure their functionality and reliability.

5 Kick detection and circulation

A kick is an undesirable influx of formation fluids, such as gas or CO2, into the wellbore that could lead to a blowout if not controlled. Kick detection is the process of identifying the signs and symptoms of a kick, such as changes in pressure, flow, or mud properties. Circulation is the process of pumping the drilling fluid and the kick fluid out of the wellbore through the choke line and the kill line, while maintaining the wellbore pressure below the formation pressure. For CCS wells, kick detection and circulation are vital skills that need to be performed quickly and accurately to prevent a loss of well control and a potential CO2 leakage.

6 Well integrity and monitoring

Well integrity is the ability of a well to perform its intended function without compromising the safety of people, the environment, or the assets. Well integrity involves ensuring that the well design, construction, operation, and maintenance are in accordance with the standards and regulations. Well monitoring is the process of collecting and analyzing data from the well and the reservoir to evaluate the performance and the condition of the well and to detect any anomalies or issues. For CCS wells, well integrity and monitoring are critical aspects of well control that need to be conducted throughout the well lifecycle, from drilling to injection to abandonment, to ensure that CO2 is safely and permanently stored underground.

7 Here’s what else to consider

This is a space to share examples, stories, or insights that don’t fit into any of the previous sections. What else would you like to add?