Methane hydrate is a promising energy resource in the near future. One of the processes of its development in the sub-seabed sediments is depressurisation: pumping-up water through a well depressurises down to the extent lower than the equilibrium, and hydrate dissociates. However, hydrate dissociation is endothermic and temperature may become lower than the equilibrium point near a well and, hence, hydrate reforms. This may cause blockage of gas-water flow in the sediment. In this study, heat and mass transfer in water-gas-sand three-phases was analysed numerically by modelling them using a three-dimensional lattice Boltzmann method. Sand grains were assumed to be spherical for simplicity and the dissolution of methane into water through the interface was also analysed. At the same time, volumetric rate of hydrate formation was obtained by comparing the model results with those of measurement.
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