15:30 〜 15:45
[SCG46-06] A method to enhance CO2 geological storage and mineralization using biodegradable chelating agents
キーワード：CO2 geological storage, chelating agent, mineral dissolution, pore property, permeability
To address climate change, greenhouse gas emissions must decline 43% by 2030, which will require scaling up to approximately 10 Gt CO2 to be removed and stored annually by 2050. Among various options for CO2 storage, the enhanced CO2 mineralization in mafic and ultramafic rocks which are enriched with calcium (Ca), magnesium (Mg), and iron (Fe), such as basalt, has garnered significant global attention. These rocks have the potential of sequestering up to 60,000,000 Gt CO2 through carbonation. However, the efficiency, capacity, and safety for CO2 mineralization in rock reservoirs still need to be improved. First, basalt reservoirs targeted for CO2 storage are usually not sufficiently reactive due to their low temperature (20-50 °C). Moreover, they generally suffer from inadequate pore space and connectivity, as well as insufficient permeability.
This study proposed an advanced CO2 geological storage and mineralization enhancement method through the innovative utilization of biodegradable chelating agents such as N,N-Dicarboxymethyl glutamic acid (GLDA). This method consists of (1) injection an acid solution containing chelating agents to improve pore space and connectivity, rock permeability through enhanced and selective mineral dissolution; (2) injection of alkaline GLDA seawater solution with captured CO2, which further expands the storage space while allowing CO2 storage take place in a stable hydraulic environment; (3) CO2 mineralized by reacting with the metal divalent leached from basalt or contained in the initial seawater with the decomposition of the chelating agents in a couple of months. This study elucidates the feasibility, effectiveness, and suitable operational conditions for implementing this enhanced CO2 storage method through comprehensive laboratory experiments.
This study proposed an advanced CO2 geological storage and mineralization enhancement method through the innovative utilization of biodegradable chelating agents such as N,N-Dicarboxymethyl glutamic acid (GLDA). This method consists of (1) injection an acid solution containing chelating agents to improve pore space and connectivity, rock permeability through enhanced and selective mineral dissolution; (2) injection of alkaline GLDA seawater solution with captured CO2, which further expands the storage space while allowing CO2 storage take place in a stable hydraulic environment; (3) CO2 mineralized by reacting with the metal divalent leached from basalt or contained in the initial seawater with the decomposition of the chelating agents in a couple of months. This study elucidates the feasibility, effectiveness, and suitable operational conditions for implementing this enhanced CO2 storage method through comprehensive laboratory experiments.