CO2 Storage in Abandoned Coal Mines

Emissions CO2 into the atmosphere have become a serious concern worldwide. Despite efforts to reduce the CO2 concentration, global CO2 emissions are increasing, and are estimated to be almost twice the current emissions by 2040 unless mitigating techniques are adopted. Many methods have been introduced to mitigate CO2 emissions to the atmosphere. One of them is to capture CO2 from stationary sources and transport, and store it in abandoned coal mines. CO2 can be stored in abandoned coal mines in three states: free in empty spaces, adsorbed on the remaining coal or dissolved in mine water. The amount of storage could be significant depending on geological characteristics of mines and engineering design parameters. It would also be possible to recover some CH4 which could offset the cost of the project. A review of the previous studies completed on CO2 sequestration in abandoned coal mines around the world and preliminary assessments of the potential in Australia are presented.