Modeling heating curve for gas hydrate dissociation in porous media

Christophe Dicharry (1) , P. Gayet (1) , G. Marion (1) , Alain Graciaa (1) , A. Nesterov (2)

1 TEFC - Thermodynamique et Energétique des fluides complexes
2 Institute of earth cryosphère

A method for modeling the heating curve for gas hydrate dissociation in porous media at isochoric conditions (constant cell volume) is presented. This method consists of using an equation of state of the gas, the cumulative volume distribution (CVD) of the porous medium, and a van der Waals-Platteeuw-type thermodynamic model that includes a capillary term. The proposed method was tested to predict the heating curves for methane hydrate dissociation in a mesoporous silica glass for saturated conditions (liquid volume = pore volume) and for a fractional conversion of water to hydrate of 1 (100% of the available water was converted to hydrate). The shape factor (F) of the hydrate-water interface was found equal to 1, supporting a cylindrical shape for the hydrate particles during hydrate dissociation. Using F = 1, it has been possible to predict the heating curve for different ranges of pressure and temperature. The excellent agreement between the calculated and experimental heating curves supports the validity of our approach.

Domaines: Chimie-Physique [physics.chem-ph]

Christophe Dicharry, P. Gayet, G. Marion, Alain Graciaa, A. Nesterov. Modeling heating curve for gas hydrate dissociation in porous media. Journal of Physical Chemistry B, 2005, 109 (36), pp.17205-17211. ⟨10.1021/jp0504975⟩. ⟨hal-00343004⟩