Insights into the Stability of Self-healing Cements Deployed in a Geothermal Wellbore

摘要

Geothermal energy has garnered global interest as a renewable, environmentally friendly, and carbon-neutral source of energy power. During the estimated 30-year operational duration of a geothermal production well, wellbore cement undergoes a minimum of two wellbore maintenance procedures. These interventions typically incur costs exceeding $1.5 million per annum per wellbore, a figure that excludes the economic ramifications associated with cessation of production during repair. Given these financial implications, the quest for advanced cementitious materials such as self-healing formulations has significantly increased in the last decade. In response to this challenge, our team has pioneered the development of tailored self-healing cements, based on a novel “Molecular Velcro” technology. This technology could mend fractures over the whole lifespan of the cement’s structure. This patented method integrates selected polymers with cement, leading to a cement composite capable of self-repairing within 24 to 72 hours post-crack initiation. Our team recently deployed polymer-modified cement formulations into a geothermal wellbore located in the Newberry Volcano, OR. About 90 samples including (1) unmodified (control) wellbore cement type H and type G samples, and samples of two self-healing cement formulations were placed into a sample holder and deployed within a geothermal wellbore at a temperature of 300°C, from July to October 2023. In this work we will present the results from chemical as well as mechanical integrity evaluations towards demonstrating the potential of these self-healing wellbore cements for geothermal energy applications.

期刊或会议名
AGU Fall Meeting 2023