abstract: â in this study, the change in the crystalline structure of gas hydrate was predicted for ternary mixture of methane-ethane-water. for this purpose, the tangent plane distance (tpd) minimization method was used. first, the calculations were performed for the binary mixtures of methane-water and ethane-water as the gas and liquid phases. the results show that for a binary mixture of th...

in this work, experimental kinetics data of methane hydrate decomposition at temperatures ranging from 272.15 to 276.15 k and at pressures ranging from 10 to 30 bars were modeled by using chemical affinity. this model proposed a macroscopic model which is independent of any intermediate mechanism like heat or mass transfer. the results show there is good agreement with experimental data. also t...

A Raman spectrometer extensively modified for deep ocean use was used to measure synthetic hydrates formed in an ocean environment. This was the first time hydrates formed in the ocean have been measured in situ using Raman spectroscopy. Gas hydrates were formed in situ in the Monterey Bay by pressurizing a Pyrex cell with various gas mixtures. Raman spectra were obtained for sI methane hydrate...

Replacement of methane with carbon dioxide in hydrate has been proposed as a strategy for geologic sequestration of carbon dioxide (CO(2)) and/or production of methane (CH(4)) from natural hydrate deposits. This replacement strategy requires a better understanding of the thermodynamic characteristics of binary mixtures of CH(4) and CO(2) hydrate (CH(4)-CO(2) mixed hydrates), as well as thermoph...

Formation of natural gas hydrate is a serious problem in the gas and oil industry because it can plug pipelines and destroy the equipment. This study aimes to evaluate the concentration effect of glycol ethers on their synergism with a commercial kinetic hydrate inhibitor (Luvicap 55W) in sweet natural gas-water systems at a constant temperature of 4 oC and pressure of 95 bar. Hydrate formation...

This collaborative effort to compare the world’s leading gas hydrate reservoir simulators is designed primarily to exchange information and insight that will lead to the improvement in simulation capability of experimental and naturally occurring gas hydrate accumulations. The initial phase of the code comparison activity achieved the simulation of five problems of increasing complexity by five...

The Krishna Godavari (KG) basin is rich in gas hydrate and exhibits an area of wide range of gas hydrate stability zone (GHSZ). In this region, we modeled the base of the gas hydrate stability zone (BGHSZ) utilizing in situ temperature measurements acquired during national gas hydrate program (NGHP) Expedition-01. The bottom simulation reflector (BSR) closely approximates the BGHSZ, and due to ...

Gas hydrates presented as form of segregated bodies have been observed on shallow subsurface sediments. However, most gas hydrate physics models describe that hydrates occur in pore space in deep subsurface sediment. A new model considers gas hydrate as segregated bodies to derive elastic properties of hydrates bearing sediments and gas hydrate saturation. The predicted elastic properties based...

The Michelsen stability and multiphase flash calculation by direct minimization of Gibbs free energy of the system at constant temperature and pressure, was used for systems containing gas hydrates. The solid hydrate phase was treated as a solid solution. The fugacities of all components of the hydrate phase were calculated as a function of compositions by the rearranged model of van der Wa...

The structure of the carbon dioxide-water interface was analyzed by X-ray diffraction and reflectivity at temperature and pressure conditions which allow the formation of gas hydrate. The water-gaseous CO2 and the water-liquid CO2 interface were examined. The two interfaces show a very different behavior with respect to the formation of gas hydrate. While the liquid-gas interface exhibits the f...