Premium
Hydrate phase equilibria in porous media: effect of pore size and salinity
Author(s) -
Østergaard Kasper K.,
Anderson Ross,
Llamedo Maria,
Tohidi Bahman
Publication year - 2002
Publication title -
terra nova
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.353
H-Index - 89
eISSN - 1365-3121
pISSN - 0954-4879
DOI - 10.1046/j.1365-3121.2002.00433.x
Subject(s) - clathrate hydrate , methane , porous medium , hydrate , porosity , mass transfer , dissociation (chemistry) , natural gas , methanol , chemical engineering , geology , thermodynamics , materials science , chemical physics , mineralogy , chemistry , chromatography , geotechnical engineering , organic chemistry , physics , engineering
Considering the ever‐increasing importance of marine gas hydrates, it is crucial to gain a better understanding of clathrate formation and decomposition in porous media. It is well established that, due to capillary effects, small‐diameter pores – similar to those found in natural sediments – act to inhibit hydrate stability. However, accurate data constraining these effects are still lacking. Here, we present experimental methane clathrate dissociation data for 3.5 mass% methanol aqueous solutions in confined silica glass pores of narrow distribution (30.6, 15.8, and 9.2 nm mean diameters). These data have been used to validate a thermodynamic model for clathrate stability porous media. Experimental data show a marked improvement on literature data – which we attribute to the experimental and interpretative methods used – and are in good agreement with the model predictions. Results suggest that mass transfer of inhibitors (methanol) and dissolved gas during clathrate formation/dissociation within the porous network plays an important role in controlling gas hydrate equilibria.