Gas hydrates form when water and natural gas combine at low temperatures and high pressures — for example, in regions of permafrost and in marine subseafloor sediments. They exist in abundance worldwide and some estimates suggest that the total amount of natural gas bound in hydrate form may exceed all conventional gas resources, or even the amount of all hydrocarbon energy — coal, oil and natu...

The hydrate/methane gas interface is studied by molecular dynamics simulations. Below the hydrate melting temperature a thin liquid film forms with an associated surface charge density and electrostatic potential. The thickness of the thin liquid film, the charge density, and electrostatic potential at the hydrate/gas interface are established at different subcooling temperatures for the first ...

A complete set of scaling criteria for gas hydrate reservoir of five-spot well system case is derived from the 3D governing equations, involving the mass balance equation, the energy balance equation, the kinetic model, the endothermic model and the phase equilibrium model. In the scaling criteria, the key parameters of the experiment are the water/gas production rates, the water injection rate...

Clathrate hydrate formation and subsequent plugging of deep-sea oil and gas pipelines represent a significant bottleneck for deep-sea oil and gas operations. Current methods for hydrate mitigation are expensive and energy intensive, comprising chemical, thermal, or flow management techniques. In this paper, we present an alternate approach of using functionalized coatings to reduce hydrate adhe...

To evaluate the gas production performance of the hydrate accumulations in the South China Sea, a numerical simulation with warm brine stimulation combined depressurization has been conducted. A dual horizontal well system is considered as the well configuration in this work. In order to reduce energy input and improve energy utilization, warm brine (<30 °C) instead of hot brine (>50 °C) is inj...

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 ...

[1] Submersible investigations of the Cascadia accretionary complex have identified localized venting of methane gas bubbles in association with gas hydrate occurrence. Acoustic profiles of these bubble plumes in the water column in the vicinity of Hydrate Ridge offshore Oregon provide new constraints on the spatial distribution of these gas vents and the fate of the gas in the water column. Th...

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...

Simulation of the system behavior of hydrate-bearing geologic media involves solving fully coupled massand heat-balance equations. In this study, we develop a domain decomposition approach for large-scale gas hydrate simulations with coarse-granularity parallel computation. This approach partitions a simulation domain into small subdomains. The full model domain, consisting of discrete subdomai...

â  abstract: in this work, the kinetics of ethane hydrate formation has been studied experimentally and a kinetic model based on chemical affinity has been described for predicting the hydrate growth process in the stirred batch reactor at a constant volume. the experiments were done with both pure water and aqueous solution of sodium dodecyl sulfate (sds). the effect of sds on formation kineti...