CARBON SEQUESTRATION
points where sequestration in geologic formations can be reliably accomplished. The existing UNGS network in the U.S. is a relevant and informative model for a candidate CDS network. At least some UNGS facilities might become candidates for hybrid UNGS-CDS opera- tions, mainly because of existing pipeline connectivity and CDS-favorable saline aquifers at depth.
Refinement of hybrid UNGS-CDS concepts should involve the following assessments:
• Geographical pairing of candi- date carbon dioxide point emit- ters (fossil-fuel electric-power plants or industrial manufactur- ing plants) with candidate CDS injection sites defined by existing UNGS facilities.
Figure 3. Strawman Design Concept (Cross Section) for a Hybrid UNGS-CDS Facility
natural gas pipelines, where appropri- ate, could substantially reduce the need for new pipeline construction. Given reasonable economic incentives — espe- cially if GHG emissions become regu- lated through a carbon market price or tax (FERC, 2020) — pipeline opera- tors might convert selected natural gas pipelines to carbon dioxide pipelines. Such conversions could be made easier if the carbon dioxide could be trans- ported as a compressed gas rather than a supercritical fluid, thereby minimizing impacts on pipeline design and opera- tions. Upon gas-pipeline delivery to the hybrid UNGS-CDS facility, the carbon dioxide could be compressed into a supercritical fluid before injection into the saline aquifer.
Streamlined Regulatory Oversight. Combining UNGS and CDS operations into a shared facil- ity could simplify regulatory oversight. Currently, regulatory oversight of com- mercial operations of U.S. natural gas pipelines and UNGS facilities are dis- tributed between federal and state agen- cies. Interstate pipelines, and UNGS facilities connected to interstate pipe- lines, are commercially regulated by the Federal Energy Regulatory Commission (FERC) whereas intrastate pipelines and intrastate UNGS facilities are com- mercially regulated by the individual states in which the intrastate facilities reside. Both for intrastate and interstate UNGS facilities, safety and operational
www.aipg.org
integrity is regulated by the Pipeline and Hazardous Materials Safety Administration (PHMSA) although PHMSA can delegate authority to states with qualified agencies.
If carbon dioxide becomes regulated through either a market price or tax, the federal government most likely will retain primacy for commercial regula- tion (FERC, 2020) of CDS pipelines and storage facilities although eventual del- egation of authority to individual states might be possible. PHMSA already administers safety rules for supercritical carbon dioxide pipelines so inclusion of compressed-gas carbon dioxide pipelines should be straightforward.
Hybrid UNGS-CDS facilities most likely would be regulated by FERC (com- mercial) and PHMSA (safety) unless or until programs were established to del- egate regulatory oversight to individual states. However, primacy of FERC and PHMSA would encourage uniform stan- dards which would otherwise be difficult to establish through unilateral actions of individual states. More uniform and standardized rules should improve safe- ty and reliability as well as reduce costs.
Conclusions and Recommendations
If CDS is to play a meaningful role in GHG mitigations, an effective sys- tem must be built to transport carbon dioxide from its points of capture to the
• Geological evaluation of candi- date UNGS sites with regard to accessibility, capacity and con- tainment of deep saline aquifers which are suitable for CDS.
• Logistical, engineering and eco- nomic analysis of options for converting selected natural gas pipelines to carbon dioxide pipe- lines.
• Design of streamlined regulation of hybrid UNGS-CDS facilities to assure safety, reliability and economic sustainability.
For each candidate UNGS-CDS site, the detailed geological assessment will be an essential element before other assessments can be made meaningful.
About the Author
James L. Gooding is Managing Director of Geoclime, LLC in Seabrook, Texas USA. Geoclime provides qual- ity and risk management consulting to energy, water, science and engineer- ing projects where geotechnical ele- ments are involved. He is a licensed Professional Geoscientist (Texas) and a Certified Manager of Quality / Organizational Excellence (American Society for Quality).
References
Dooley, J.J., Dahowski, R.T., Davidson, C.L., Wise, M.A., Gupta, N., Kim, S.H., Malone, E.L., 2006, Carbon Dioxide capture and geologic storage: A core element of a global energy technology strategy to address climate change: Battelle Joint Global Change Research
Oct.Nov.Dec 2021 • TPG 51
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56
