Radiocarbon as a Reactive Tracer for Tracking Permanent CO₂ Storage in Basaltic Rocks [electronic resource]

• Ngôn ngữ: eng
• Ký hiệu phân loại: 543.85 Gas chromatography
• Thông tin xuất bản: Oak Ridge, Tenn. : Distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy, 2015
• Mô tả vật lý: Size: 47 p. : , digital, PDF file.
• Bộ sưu tập: Metadata
• ID: 268183
• Chủ đề: 1. 01 coal, lignite, and peat; 2. 15 geothermal energy; 3. 20 fossil-fueled power plants; 4. 54 environmental sciences; 5. 58 geosciences

Tóm tắt

 In view of concerns about the long-term integrity and containment of CO<
 sub>
 2<
 /sub>
  storage in geologic reservoirs, many efforts have been made to improve the monitoring, verification and accounting methods for geologically stored CO<
 sub>
 2<
 /sub>
 . Our project aimed to demonstrate that carbon-14 (<
 sup>
 14<
 /sup>
 C) could be used as a reactive tracer to monitor geochemical reactions and evaluate the extent of mineral trapping of CO<
 sub>
 2<
 /sub>
  in basaltic rocks. The capacity of a storage reservoir for mineral trapping of CO<
 sub>
 2<
 /sub>
  is largely a function of host rock composition. Mineral carbonation involves combining CO<
 sub>
 2<
 /sub>
  with divalent cations including Ca<
 sup>
 2+<
 /sup>
 , Mg<
 sup>
 2+<
 /sup>
  and Fe<
 sup>
 2+<
 /sup>
 . The most abundant geological sources for these cations are basaltic rocks. Based on initial storage capacity estimates, we know that basalts have the necessary capacity to store million to billion tons of CO<
 sub>
 2<
 /sub>
  via in situ mineral carbonation. However, little is known about CO2-fluid-rock reactions occurring in a basaltic storage reservoir during and post-CO<
 sub>
 2<
 /sub>
  injection. None of the common monitoring and verification techniques have been able to provide a surveying tool for mineral trapping. The most direct method for quantitative monitoring and accounting involves the tagging of the injected CO<
 sub>
 2<
 /sub>
  with 14C because 14C is not present in deep geologic reservoirs prior to injection. Accordingly, we conducted two CO<
 sub>
 2<
 /sub>
  injection tests at the CarbFix pilot injection site in Iceland to study the feasibility of 14C as a reactive tracer for monitoring CO<
 sub>
 2<
 /sub>
 -fluid-rock reactions and CO<
 sub>
 2<
 /sub>
  mineralization. Our newly developed monitoring techniques, using 14C as a reactive tracer, have been successfully demonstrated. For the first time, permanent and safe disposal of CO<
 sub>
 2<
 /sub>
  as environmentally benign carbonate minerals in basaltic rocks could be shown. Over 95% of the injected CO<
 sub>
 2<
 /sub>
  at the CarbFix pilot injection site was mineralized to carbonate minerals in less than two years after injection. Our monitoring results confirm that CO<
 sub>
 2<
 /sub>
  mineralization in basaltic rocks is far faster than previously postulated.