Microscale Processes and Dynamics during CH4–CO2 Guest-Molecule Exchange in Gas Hydrates
نویسندگان
چکیده
The exchange of CH4 by CO2 in gas hydrates is interest for the production natural from methane hydrate with net zero climate balance, and managing risks that are related to sediment destabilization mobilization after gas-hydrate dissociation. Several experimental studies on dynamics efficiency process exist, but results seem be partly inconsistent. We used confocal Raman spectroscopy map an area several tens hundreds µm a sample during its exposure liquid gaseous CO2. On this scale, we could identify follow different processes occur parallel. Next guest-molecule exchange, dissociation also contributes release CH4. During our examination period, about 50% was bound molecules, while other half new formation hydrates. evaluated single grains confirmed applied diffusion equation quantify process. Obtained coefficients range 10?13–10?18 m2/s. propose use analytical simple robust modeling combine it additional term
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ژورنال
عنوان ژورنال: Energies
سال: 2021
ISSN: ['1996-1073']
DOI: https://doi.org/10.3390/en14061763