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Li, Xiaochun

Publications and source records attributed to Li, Xiaochun.

5 records
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DOE OSTI2022

A Hierarchical Framework for CO2 Storage Capacity in Deep Saline Aquifer Formations

Carbon dioxide (CO 2 ) storage in deep saline aquifers is a vital option for CO 2 mitigation at a large scale. Determining storage capacity is one of the crucial steps toward large-scale deployment of CO 2 storage. Results of capacity assessments tend toward a consensus that sufficient resources are available in saline aquifers in many parts of the world. However, current CO 2 capacity assessments involve significant inconsistencies and uncertainties caused by various technical assumptions, storage mechanisms considered, algorithms, and data types and resolutions. Furthermore, other constraint factors (such as techno-economic features, site suitability, risk, regulation, social-economic situation, and policies) significantly affect the storage capacity assessment results. Consequently, a consensus capacity classification system and assessment method should be capable of classifying the capacity type or even more related uncertainties. We present a hierarchical framework of CO 2 capacity to define the capacity types based on the various factors, algorithms, and datasets. Finally, a review of onshore CO 2 aquifer storage capacity assessments in China is presented as examples to illustrate the feasibility of the proposed hierarchical framework.

58 GEOSCIENCES↗
DOE OSTI2021

Impact of reservoir parameters and wellbore permeability uncertainties on CO 2 and brine leakage potential at the Shenhua CO 2 Storage Site, China

Here, this paper describes a system-level risk assessment for the Shenhua CO 2 storage site, China, using the National Risk Assessment Partnership Integrated Assessment Model for Carbon Storage (NRAP-IAM-CS). Here, we begin by determining the optimal number of Monte Carlo (MC) simulations to achieve CO 2 and brine leakage result convergence. Then, we calculate mass CO 2 and brine leakage to the atmosphere and a hypothetical shallow aquifer. Finally, we assess the geochemical impacts in the event of leakage as if there were a shallow freshwater aquifer at the Shenhua site. Simulation results show that leakage results tend to stabilize after 300 Monte Carlo simulations. When the three wells on site are assigned a permeability of 10 -11 m 2 (representing significantly leaking wells), moderate CO 2 and brine leakages occur, and the percentage of CO 2 leakage exceeds the threshold value we set based on the Intergovernmental Panel on Climate Change (IPCC). This is, however, unlikely to be the case for the Shenhua site. For all the other scenarios, the CO 2 leakage is trivial although there is still the possibility of CO 2 leakage into the groundwater aquifer exceeding the 1% threshold over 1000 years, assuming constant legacy wellbore permeability. For the significantly leaking scenario, there is a 10% probability to have a moderate (2.7 × 10 7 m 3 ) leakage-affected volume in the shallow aquifer with the pH below 6.5, and a large (1.4 × 10 8 m 3 ) volume with the total dissolved solids (TDS) above 500 ppm, hence pH and TDS may be considered for site monitoring plans. Based on the simulation results, there is a very low probability of significant CO 2 /brine leakage through the existing wells at the Shenhua CO 2 storage site.

58 GEOSCIENCES↗