The Big Sky Carbon Sequestration Partnership, one of seven U.S. Department of Energy (DOE) regional partnerships conducting carbon storage research, recently injected 1,000 tonnes of CO2 into the Grande Ronde Basalt Formation in eastern Washington state.
This first-of-its-kind injection is part of research to determine if basalt formations could provide a long-term solution for storing CO2, a potent greenhouse gas produced by sources like coal-fired power plants. This idea is commonly called carbon capture and storage (CCS).
The half-mile-deep basalt formation was created by layer upon layer of ancient lava flows, DOE said in an Aug. 13 statement. As the lava cooled in each layer, the upper portion solidified faster and became more cracked and porous than the slower-cooling lower portion of the layer.
Lab testing done by DOE’s Pacific Northwest National Laboratory (PNNL) on samples from the region shows that chemicals in the basalt react with CO2, converting it to solid calcium carbonate, or limestone, over just a few months. By injecting liquid-like CO2 into the porous part of a layer, researchers hope for the same results, which would prevent gaseous CO2 from escaping. Thick, impermeable basalt above the injection layer provides further insurance that the CO2 will remain in place while the chemical conversion occurs, DOE noted.
Re-injection characterization activities identified no significant faults or fractures at this site, and the groundwater in and immediately above the injection layer was already unsuitable for human use because of its high fluoride content, DOE said.
Over the next 14 months, researchers will test fluid samples from the injection well to determine changes in the chemical composition compared to pre-injection samples and computational predictions. Sensors in the well will monitor for potential CO2 leakage, detecting it before it reaches the surface or area aquifers. Rock samples will then be collected and tested for limestone crystals at the end of the 14-month period, and the well will be capped.
Major parts of Washington, Oregon, and Idaho lie above the ancient lava flows tested in this project. Similar underlying basalt formations are common worldwide and could be put to the same use, helping reduce industrial CO2 emissions by permanently storing them underground.
Led by Montana State University, the Big Sky Carbon Sequestration Partnership is conducting this research project with the Battelle Memorial Institute out of Columbus, Ohio, which operates PNNL. Boise Inc., a packaging and paper products company headquartered in Boise, Idaho, owns the property in Wallula, Wash., where the injection took place. Praxair provided the CO2 for the test, and Royal Dutch Shell and electric utility Portland General Electric are assisting the $12m project with additional funding. Schlumberger Carbon Services is providing some of the funds for modeling and geophysical services.
The Regional Carbon Sequestration Partnerships were formed in 2003 to investigate safe, permanent, and economical methods to store CO2 emissions in their respective areas of the country. The Big Sky partnership covers Montana, Wyoming, Idaho, South Dakota, and eastern Washington and Oregon.