The effects of porous medium heterogeneity on methane hydrate formation, water flow through
the heterogeneous hydrate-bearing sand, and hydrate dissociation were observed in an experiment
using a heterogeneous sand column with prescribed heterogeneities. X-ray computed tomography
(CT) was used to monitor saturation changes in water, gas, and hydrate during hydrate formation,
water flow, and hydrate dissociation. The sand column was packed in several segments having
vertical and horizontal layers with two distinct grain-size sands. The CT images showed that as
hydrate formed, the water and hydrate saturations were dynamically redistributed by variations in
capillary strength of the medium (the tendency for a material to imbibe water), which changed
with the presence and saturation of hydrate. Water preferentially flowed through fine sand near
higher hydrate-saturation regions where the capillary strength was elevated relative to the lower
hydrate saturation regions. Hydrate dissociation initiated by depressurization varied with different
grain sizes and hydrate saturations.
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:BVAU.2429/2201 |
| Date | 07 1900 |
| Creators | Seol, Yongkoo, Kneafsey, Timothy J. |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | English |
| Detected Language | English |
| Type | text |
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