Recent Advances in Geological Storage: Trapping Mechanisms, Storage Sites, Projects, and Application of Machine Learning

Abstract

A significant amount of carbon dioxide (CO2) is being released into the atmosphere as a result of the acceleration of industrialization and increased energy consumption, which are causing a rise in world temperatures. Despite the fact that nations all over the world have actively participated in CO2 storage projects, there is still not enough to moderate global temperatures. Therefore, there is an urgent need for the development of CO2 sequestration technologies. The main geological storage trapping mechanisms are discussed in this work along with an analysis of the major influencing variables. Additionally, the benefits and drawbacks of significant storage locations and current research hotspots are explored. Storage project development across the globe is outlined. The use of machine learning for CO2 sequestration is reviewed toward the end. This extensive review reveals that the main variables affecting CO2 capture capacity are hydrodynamic and geochemical. The sequestration capability of various storage sites is significantly influenced by the reservoir characteristics and implementation methodologies. The successful implementation of the storage project is determined by local policies and public support. The development of machine learning technologies makes storage projects safer and more dependable.

Minireview on CO2 Storage in Deep Saline Aquifers: Methods, Opportunities, Challenges, and Perspectives

“…This reaction may lead to the formation of fractures or cracks to the cap rock and corrosion of the pore space. 7 Moreover, evaluating the integrity of cap rock is an important factor for any storage site. Investigation of geomechanical properties of cap rock by laboratory experiments and seismic monitoring can be done to assess the seal integrity of cap rock.…”

“…However, sampling cores from different depths and locations of the storage reservoir and seismic survey data can help to overcome these problems. As CO 2 will be stored under cap rock through structural and stratigraphic trapping for thousands of years, it has the potential to react with the cap rock. This reaction may lead to the formation of fractures or cracks to the cap rock and corrosion of the pore space . Moreover, evaluating the integrity of cap rock is an important factor for any storage site.…”

“…These reactions can corrode the pores of the cap rock or create cracks, consequently diminishing the cap rock's effectiveness in blocking CO 2 . 7 Residual trapping refers to the trapping of CO 2 in pore space. When supercritical CO 2 (Sc-CO 2 ) is injected, the gas moves upward through the pore space and some CO 2 , which is immobilized, is trapped in the pore space.…”

“…Nevertheless, since CO 2 will be in prolonged contact with the cap rock, it can undergo reactions with the cap rock. These reactions can corrode the pores of the cap rock or create cracks, consequently diminishing the cap rock’s effectiveness in blocking CO 2 …”

“…The reactions will result in stable carbonates which can either form scale on pore walls or aggregate as small particles . The effectiveness of mineral trapping depends on the pressure and temperature of the formation as well as the minerology of the host rock, pH, and groundwater chemistry. ,, However, mineral trapping provides permanent storage of CO 2 , but it requires a very long period. Therefore, the overall effects of mineral trapping might not be evident for several decades to even hundreds of years or beyond .…”