Loss of stress support caused by hydrate dissociation may result in a significant reduction of rock strength. The strength of a hydrate-bearing sedimentary formation is a function of the strengths of inter-granular bonds and the interactions between the rock grains and the hydrates in the pore space. Myriads of such bonds and interactions define the macroscopic rock strength parameters. We expe...

in this work the effect of electrolytes on hydrate formation was investigated. to do so, a new model was used in predicting the hydrate formation conditions in presence of both single and mixed electrolyte solutions. the new model is based on the van der waals - platteeuw hydrate equation of state. in order to evaluate the values for the activity of water in electrolyte solutions the simplified...

An hybrid absorption-hydration method was adopted to recover C2H4 from C2H4/CH4 binary gas mixtures and the hydrate formation conditions of C2H4/CH4 mixtures was studied experimentally in diesel in water (w/o) emulsions. Span 20 at a concentration of 1.0 wt% in the aqueous phase was added to form water in diesel emulsions before hydrate formation and then hydrate in diesel slurry was separated ...

The formation of hydrate plugs in oil and gas pipelines is a serious industrial problem and recently there has been an increased interest in the use of alternative hydrate inhibitors as substitutes for thermodynamic inhibitors like methanol. We show here that antifreeze proteins (AFPs) possess the ability to modify structure II (sII) tetrahydrofuran (THF) hydrate crystal morphologies by adherin...

CO2 hydrate formation and dissociation is crucial for hydrate-based CO2 capture and storage. Experimental and calculated phase equilibrium conditions of carbon dioxide (CO2) hydrate in porous medium were investigated in this study. Glass beads were used to form the porous medium. The experimental data were generated using a graphical method. The results indicated the decrease of pore size resul...

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...

Small-scale morphology of gas hydrate is important for understanding the formation of gas hydrate deposits, for estimating the concentrations of gas hydrate from geophysical data, and for predicting their response to climate change or commercial production. The recent use of borehole pressure coring tools has allowed marine gas-hydrate-bearing sediments to be recovered with centimeter to sub-mi...

Permeability is one of the key factors that determine the fluids flow capacity and production potential of hydrate deposits. In this study, an experimental setup is developed to investigate the flow properties of the porous media, and the permeabilities to water are measured in the unconsolidated porous media with or without hydrate deposition in the pores. A specialized method of precisely con...

Conceptually new methods of hydrate formation are proposed. The first one is based on the shock wave impact on a water-bubble medium. It is shown that the hydrate formation rate in this process is typically very high. A gas hydrate of carbon dioxide was produced. The process was experimentally studied using various initial conditions, as well as different external action magnitudes. The obtaine...

Based on currently available data from site measurements in the Shenhu Area of the South China Sea, methane hydrate dissociation behavior by depressurization is studied in a one-dimensional experimental apparatus. According to time variation of temperature, resistance and gas production, the hydrate dissociation process is divided into three stages: free gas release, rapid dissociation and grad...