Why a thermodynamic approach for CO2 disposal and H2 or CH4 extraction from marine gas hydrate deposits

Atanas Vasilev, Bjørn Kvamme, Rositsa Pehlivanova, Eva Marinovska, Ivan Genov

Abstract:
If 1% of the methane in gas hydrate deposits escapes to the atmosphere, global warming will become catastrophic, but H2 or methane can be extracted from hydrates with reliable CO2 burial in quantities that make the extracted fuel the only energy source with a significant negative carbon footprint in the atmosphere. The analysis of the problems registered during the test extraction of methane from hydrates which stop the development of efficient technologies for the exploitation of both permafrost and marine gas hydrate deposits, proves the failure of the simplified approach based on equilibrium P-T phase curves supported by laboratory experiments. They are also the basis for wrong conclusions about gas hydrates in the Black Sea, as unpromising for the extraction of CH4 by its replacement in the hydrate with CO2, due to the high temperature of the deep-sea bottom of 9 °С. The consistent application of a thermodynamic approach shows the injection of which gas mixtures make it possible the exothermic process from the formation of CO2-hydrate to release CH4, and the Gibbs energy analysis proves the high stability of the newly formed hydrate. The released gas can be converted to H2 and CO2 using steam, a standard process first patented by Norsk Hydro in 1913.

Keywords:
thermodynamics, CCS, CO2, hydrates, H2

XI National Geophysical Conference, 9th June 2023, DOI: 10.48368/bgs-2023.1.N9

Author information:
Author: Atanas Vasilev
E-mail: gasberg@io-bas.bg
Affiliation: Institute of Oceanology – Bulgarian Academy of Sciences

Author: Bjørn Kvamme
E-mail: bkvamme@strategic-carbonllc.com
Affiliation: Strategic Carbon LLC, 20 Ladd St., Suite 200, Portsmouth, NH 03801, USA

Author: Rositsa Pehlivanova
E-mail:
Affiliation: Institute of Oceanology – Bulgarian Academy of Sciences

Author: Eva Marinovska
E-mail: evarmarinovska@gmail.com
Affiliation: Sofia University „St. Kliment Ohridski”

Author: Ivan Genov
E-mail:
Affiliation: Institute of Oceanology – Bulgarian Academy of Sciences

Acknowledgements:
The research is within two projects:
• Scientific Research Fund project KP-06-OPR04/7 GEOHydrate: Geothermal evolution of marine deposits of gas hydrates – Danube paleodelta, Black Sea (2018–2023);
• EC H2020 project 101000518 DOORS: Developing Optimal and Open Research Support for the Black Sea (2021–2025).

How to cite:
Vasilev, A., Kvamme, B., Pehlivanova, R., Marinovska, E., & Genov, I. (2023). Защо термодинамичен подход за погребване на СО2 и добив на СН4 и/или Н2 от морски газхидратни находища. XI National Geophysical Conference, 9th June 2023. https://doi.org/10.48368/BGS-2023.1.N9