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 drop...

Gas hydrates dominated by methane naturally occur in deep marine sediment along continental margins. These compounds form in pore space between the seafloor and a sub-bottom depth where appropriate stability conditions prevail. However, the amount and distribution of gas hydrate within this zone, and free gas below, can vary significantly at different locations. To understand this variability, ...

The first aspect is the problem of how to gain a better understanding of the distribution and abundance of gas hydrates in continental slope sediments at the present day. Mark Maslin (University College London) and Nick Langhorne (Office of Naval Research, USA) both emphasized that while the potential distribution of hydrates can be defined, based on the pressure and temperature limits of their...

Gas hydrates, or more generally clathrate hydrates, are a type of inclusion compound and take the form of nonstoichiometic solid crystalline materials formed from water and small guest molecules. Under sufficient pressure of the guest material and at specific temperatures, 3D hydrate structures are formed by the stacking of polyhedral cages of hydrogenbonded water molecules. Suitably sized gues...

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 waals ...

In 1995, the U.S. Geological Survey made the first systematic assessment of the in-place natural gas hydrate resources of the United States. That study suggested that the amount of gas in the gas hydrate accumulations of northern Alaska probably exceeds the volume of known conventional gas resources on the North Slope. Researchers have long speculated that gas hydrates could eventually be a com...

Gas hydrates formed in the conditions of high pressure and low temperature deep sea process oil gas transportation, natural hydrate (NGH), will seriously affect safety drilling completion operations marine equipment threaten platform. How to prevent formation production transportation has become an urgent problem for industry. For this reason, view NGH producing NGH, phase equilibrium calculati...

This study establishes the ability of hydrate formation to initiate internal corrosions along natural gas pipelines. The identified corrosion types, which are cavitations, erosion and corrosions by chemical reactions, are capable to individually or collectively initiate pitting and stress cracking corrosions which are also dangerous to gas pipelines. The impacts of these corrosion types are cla...