Characteristics such as temperature and pressure profiles for methane hydrate formation and dissociation in pure water, simulated seawater, and water–surfactant systems have been established. A hysteresis effect has been observed for repeated formation–dissociation cycles of the same methane–water system. In an attempt to maximize the uptake of methane during methane hydrate formation, the addi...

The kinetics of nucleation of one-component gas hydrates in aqueous solutions are analyzed. The size of the hydrate nucleus and the work for nucleus formation are determined as functions of the supersaturation Dm: Expressions for the stationary rate J of hydrate nucleation are derived. These expressions describe the JðDmÞ dependence for homogeneous nucleation and for heterogeneous nucleation at...

The separation of azeotropic mixtures has conventionally been one the most challenging tasks in industrial processes due to fact that components mixture will undergo gas–liquid phase transition at same time. We proposed a method for separating azeotropes using hydrate formation as solid–liquid transition. feasibility hydrate-based is determined by analyzing crystal structure and chemical bonds ...

Within the subseafloor, methane hydrates form within the gas hydrate stability zone (GHSZ). Two areas within the Gulf of Mexico (GOM) were investigated in this study: Keathley Canyon and Atwater Valley. The GOM contains an underlying petroleum system and deeply buried, yet dynamic salt deposits. Salt tectonics and fluid expulsion upward through the sediment column lead to the formation of fract...

The gas hydrate petroleum system in the permafrost of the Qilian Mountains, which exists as an epigenetic hydrocarbon reservoir above a deep-seated hydrocarbon reservoir, has been dynamic since the end of the Late Pleistocene because of climate change. The permafrost limits the occurrence of gas hydrate reservoirs by changing the pressure-temperature (P-T) conditions, and it affects the migrati...

Experimental data on the kinetics of propane hydrate dissociation at 0.1 MPa and different external temperatures were obtained. A two-stage mechanism of hydrate dissociation was observed visually. In the first stage hydrate dissociated into metastable water and gas. During the second stage the metastable water crystallized into ice. The release of metastable water during hydrate dissociation an...

One of the most important methods of transporting natural gas in Iran and other parts of the world is the utilization of a network of pipelines. Compression station and turbo compressor units play an important role in gas supply through pipelines. One of the primary concerns in these units is the reduction of fuel consumption. By cooling of exhaust gas from the source station, the pressure ...

The effect of the concentration of kinetic hydrate inhibitors, polyvinylpyrrolidone (PVP), and polyvinylcaprolactam (PVCap) on the onset and growth of synthetic natural gas hydrates is investigated by measuring the hydrate onset time and gas consumption rate. Although the hydrate onset time is extended by increasing the concentration from 0.5 to 3.0 wt % for both PVP and PVCap, the growth rate ...

Seafloor methane release due to the thermal dissociation of gas hydrates is pervasive across the continental margins of the Arctic Ocean. Furthermore, there is increasing awareness that shallow hydrate-related methane seeps have appeared due to enhanced warming of Arctic Ocean bottom water during the last century. Although it has been argued that a gas hydrate gun could trigger abrupt climate c...