CO₂ Geological Sequestration Mechanism And Potential Capacity Analysis Of Deep Brine Aquifers In The Shuangtaizi Natural Reserve

Nowadays, CO₂ density is increasing led by the development of human society, and the greenhouse effect become more and more obvious. Climate problem has drawn international attention and become a common topic. CO₂ Geological Sequestration can be effective in reducing CO₂ emissions from human activities into the atmosphere, and it is an effective way to mitigate global climate change. CO₂ Geological Sequestration can be stored into depleted oil and gas reservoirs, coal seam that can not be mined brine aquifers and deep ocean and so on. Brine aquifers in Sedimentary basin have a huge volume, which provides a huge potential for CO₂ storage. This paper focuses on CO₂ geological storage mechanism of the deep brine aquifers in sedimentary basin. Take Shuangtaizi Natural Reserve as an example, this paper analysis different calculating methods of CO₂ storage account under various ways, with the common international pyramid evaluation methods, and analysis CO₂ Geological Sequestration potential capacity in deep brine aquifers within the wetlands.When storing, CO₂ exits in supercritical form, and there are matching store sites (stable cap, high-quality reservoirs, etc.). After injection, CO₂ can be trapped in brine aquifers in two ways: physical trapping and chemical trapping which include structural trapping, residual trapping, solubility trapping and mineral trapping. Different methods have different sequestration time. When actually injecting CO₂, it is not a single physical or chemical trapping mechanism, but a integrated progress of all these forms, which is called hydrodynamic trapping.Take Shuangtaizi Natural Reserve as an example, preliminarily estimate theoretical trap stock is 3.4048Mt, effective trap stock is 6.8096×10^-2Mt and actual trap stock is 5.1072×10^-2Mt. This shows there is a great potential of CO₂ Geological Sequestration in study area.