Using Biomineralization Sealing for Leakage Mitigation in Shale during CO2 Sequestration

Montana Emergent Technologies, Inc., (MET) in conjunction with the Center for Biofilm Engineering at Montana State University, proposes to investigate the feasibility of using biomineralization-based technology to seal unwanted leakage pathways relative to carbon dioxide stored in deep geologic formations. The title of this Small Business Technology Transfer Research Phase I project is Using Biomineralization Sealing for Leakage Mitigation in Shale during CO2 Sequestration. The Principal Investigator for this project, Dr. Robin Gerlach, is a world-renowned leader in biomineralization technology. This Phase I STTR proposal deals with Topic 17a, Carbon Storage Technologies/Advanced Geologic Storage Technologies. The implementation of this technology will allow the Nation to store CO2 underground for many years with less danger of it leaking back to the surface. MET proposes a method of mitigating leakage or re-plugging abandoned wells at CO2 storage sites. These sites are of high potential interest to prevent leakage of CO2 injected for geologic carbon sequestrationparticularly in geologic formations where large numbers of abandoned wells are present. Estimates of abandoned wells in the U.S and abroad range in the millions, all of which have a high probability of leaking. While CO2 resistant cements and ultrafine cements are being developed, technologies that can be delivered via low viscosity fluids could have significant advantages including the ability to plug small aperture leaks such as fractures or delamination interfaces. Additionally the method can be used to plug rock formation pore space around the wellbore in particularly problematic situations. Current technologies for sealing leaking CO2 sequestration sites, such as fine cement injection, have disadvantages and the DOE is looking for effective alternatives. Our technological solution is based on microbial biofilms that are capable of inducing the precipitation of crystalline calcium carbonate using the process of ureolysis. This method has the potential to reduce formation permeability and lower the risk of unwanted upward CO2 migration. Prior research by our team in this field has been limited to the study of sandstone-based geologic formations. MET has become aware of needs expressed by leading oilfield service companies to target the biomineralization sealing technology in formations composed of shale. Commercial Applications and Other Benefits Montana Emergent Technologies will commercialize this novel biomineralization technology to seal leakage pathways in fractured shale formations around well bores for CO2 sequestration. It will not only increase the long-term security of carbon dioxide sequestration, but also gives the oil industry another tool to economically seal leaking wells that might become an environmental problem.