TY - JOUR AU - Oochi, Ryosuke AU - Aoyama, Kengo AU - Ueda, Akira PY - 2020 DA - 2020/02/12 TI - Zero-Emission Geothermal Power Generation: Experimental Study on Carbonate Mineralization through CO<sub>2</sub>-Andesitic Pyroclastic Rock Interaction at Oku-Aizu Geothermal Plant JO - Journal of Energy and Power Technology SP - 002 VL - 02 IS - 01 AB - In order to achieve advancement in zero-emission geothermal power generation for fixing the CO2 in the geothermal fluids to the carbonate minerals after binary power generation and reinjection of the fluid into the reservoir, batch-type experiments and geochemical simulations of CO2-andesitic pyroclastic rock interaction (tuff from Oku-Aizu geothermal area) were performed at 150 °C with and without CO2 gas for 15 days. Despite the low Ca content (0.9% wt.%) in the rock, the Ca2+ concentrations in the solutions that were reacted with CO2 were observed to initially increase rapidly and then decreased after two days. In contrast, the Ca2+ concentrations in the solutions reacted with Ar gas remained almost constant. The solutions reacted with CO2 gas became oversaturated with respect to the carbonate minerals according to saturation degree with respect to calcite. These findings along with the other previously available data demonstrated that Ca2+ in calcite and glass in the rocks were dissolved into the fluid with CO2 gas and were fixed as carbonate minerals within a few days. SN - 2690-1692 UR - https://doi.org/10.21926/jept.2001002 DO - 10.21926/jept.2001002 ID - Oochi2020 ER -