Dry Flow Technology as Flow Assurance in Methane Hydrate Development

Preventing pipeline blockages caused by gas hydrate formation is a critical issue for gas transportation through subsea pipelines. We propose a novel approach, “dry flow”, as a means of preventing gas hydrate blockages in high-pressure gas pipelines. “Dry flow” technology comprises three stages: a separation process to remove water from gas using a separator, a conversion process in which any remaining water is transformed into hydrate particles, and a transportation process in which the hydrate particles are conveyed as a aerosol using pneumatic pressure. Dry flow prevents pipeline blockage by inhibiting the formation of a bridging structure, which reinforces the cohesive force of hydrate particles and adhesive force between hydrate and pipe wall. In this study, we conducted a laboratory experiment using a flow loop to investigate gas flow regimes with disseminated hydrate particles and verified that hydrate particles do not agglomerate under dry conditions. We compared experimental data with the estimation of a phenomenological model of gas–solid flow and numerical simulation results and found that a dilute-phase flow was achieved without gas hydrate agglomeration. This study verified our hypothesis that hydrate deposition does not occur under dry conditions and validated dry flow technology.