Direct mineralization of atmospheric CO<sub>2</sub>using natural rocks in Japan
Corey Myers, Takao Nakagaki
Abstract
Abstract Gas-solid mineralization of atmospheric CO 2 using naturally abundant surface rocks under ambient conditions and without thermochemical treatment was analyzed for application in Japan. Based on an empirically-verified theoretical framework, a tiered greenhouse containing finely ground rocks was designed with low-speed induced airflow to realize CO 2 mineralization reactions over 1 year. Negative CO 2 emissions were calculated accounting for CO 2 emissions from energy generation, materials production, and removal of vegetation and soil. Under practicable operating conditions, negative emissions using crystalline surface rocks in Japan can reach ∼7.6 Gt-CO 2 /y achieved across 726 sites. The average energy requirement was calculated to be 1.5 GJ t −1 -CO 2 with an average land requirement of 1.1 km 2 per Mt-CO 2 annual removal capacity. Carbon debt is paid off after 60 d of operation.