TY - JOUR
T1 - Hydrate phase equilibria in porous media
T2 - Effect of pore size and salinity
AU - Øtergaard, Kasper K.
AU - Anderson, Ross
AU - Llamedo, Maria
AU - Tohidi, Bahman
PY - 2002/10
Y1 - 2002/10
N2 - 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.
AB - 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.
UR - http://www.scopus.com/inward/record.url?scp=0036800989&partnerID=8YFLogxK
U2 - 10.1046/j.1365-3121.2002.00433.x
DO - 10.1046/j.1365-3121.2002.00433.x
M3 - Article
SN - 1365-3121
VL - 14
SP - 307
EP - 312
JO - Terra Nova
JF - Terra Nova
IS - 5
ER -