In the heart of China’s Sichuan province, researchers are delving into a fascinating intersection of biology and geology that could revolutionize how we approach rock reinforcement in the energy sector. Dr. XIAO Weimin, a professor at Sichuan Agricultural University, and his team are exploring the acid erosion durability of a method known as microbially induced calcite precipitation (MICP). This innovative technique, which uses bacteria to induce calcium carbonate precipitation, has been widely used for soil and rock reinforcement, but its resilience against acid erosion has remained largely unexplored—until now.
The team’s recent study, published in *Yantu gongcheng xuebao* (translated to *Rock and Soil Mechanics*), sheds light on the potential of MICP to seal rock joints effectively, even in acidic environments. “The key finding is that the MICP-treated rock joints maintain their sealing capabilities remarkably well, even after exposure to acidic conditions,” says Dr. XIAO. “This could have significant implications for the energy sector, particularly in areas where rock formations are prone to acid erosion.”
The study involved subjecting MICP-treated artificial rock joint specimens to various pH levels (4, 5, and 7) and erosion times (7, 14, and 28 days). The results were striking: the amount of dissolved calcium carbonate increased with lower pH levels and longer erosion times, but the dissolution was primarily concentrated around the edges of the specimens. Importantly, the permeability of the rock joints decreased by 97% after MICP treatment, and even after acid erosion, the permeability remained significantly lower than before treatment.
“This research is a game-changer for the energy sector,” says Dr. WENG Jinyao, a co-author of the study and also affiliated with Sichuan Agricultural University. “In oil and gas extraction, for instance, maintaining the integrity of rock formations is crucial. Our findings suggest that MICP could be a reliable method for sealing rock joints, even in challenging environments.”
The implications extend beyond oil and gas. In geothermal energy, where rocks are often exposed to harsh chemical conditions, MICP could provide a durable solution for sealing fractures and enhancing the stability of rock masses. Additionally, in mining operations, the ability to reinforce rock structures against acid erosion could lead to safer and more efficient extraction processes.
The study’s findings are particularly relevant for companies like Jiangxi Youse Construction (Group) Co., Ltd., where Dr. ZHONG Jianmin, another co-author, is based. “This research provides a scientific basis for applying MICP technology in rock mass projects,” Dr. ZHONG notes. “It’s an exciting development that could lead to more robust and cost-effective solutions for rock reinforcement.”
As the energy sector continues to evolve, the need for innovative and sustainable solutions becomes ever more pressing. The work of Dr. XIAO and his team offers a promising path forward, one that could reshape how we approach rock reinforcement in the years to come. With further research and development, MICP could become a cornerstone of modern engineering practices, ensuring the stability and safety of rock formations in even the most challenging environments.