The synergistic effect of thermodynamic promoter tetrafluoroethane (R134a) and kinetic promoter sodium dodecyl sulfate (SDS) can significantly improve the phase equilibrium conditions required for CO hydrate formation and promote rapid generation of CO hydrate. Based on this, this study investigates the influence of SDS and R134a synergy on the separation of CO/H mixed gas using the hydrate method. The research reveals that without SDS addition, R134a hydrate forms first at the gas-liquid interface before CO hydrate induction, hindering gas-liquid exchange.
View Article and Find Full Text PDFRapid formation of the CO hydrate can be significantly induced by the gaseous thermodynamic promoter 1,1,1,2-tetrafluoroethane(R134a) due to the mild phase equilibrium conditions, although the formation mechanism and dynamic behavior are not clear. Therefore, a visual experimental system was developed to study the effects of different concentrations of R134a on the induction time, gas consumption, and growth morphology of the CO hydrate. At the same time, the combined effects under stirring and sodium dodecyl sulfate (SDS) systems were also studied.
View Article and Find Full Text PDFThe exploitation of natural gas hydrate is always hindered by the migration of water and sands due to gas production. Depressurization combined with thermal stimulation is an effective method for hydrate dissociation. This paper reported the influence of gas-liquid-solid migration on morphological change of hydrate sediments in natural gas production using visualization method.
View Article and Find Full Text PDFCold storage using hydrates for cooling is a high-efficiency technology. However, this technology suffers from problems such as the stochastic nature of hydrate nucleation, cyclic hydrate formation instability, and a low cold discharge rate. To solve these problems, it is necessary to further clarify the characteristics of hydrate formation and dissociation in different systems.
View Article and Find Full Text PDFAn experimental apparatus was developed to synthesize natural gas hydrates and measure the thermal conductivity of hydrate-bearing sediments in situ. The apparatus works over a temperature range varying from -20 °C to 50 °C and up to a maximum pressure of 20 MPa. This apparatus is mainly composed of a thermal conductivity test system and a reaction cell, into which a lab-fabricated thermistor probe is inserted.
View Article and Find Full Text PDFTetrahydrofuran (THF) hydrate has long been used as a substitute for methane hydrate in laboratory studies. This article investigated the formation and dissociation characteristics of THF hydrate in porous media simulated by various-sized quartz glass beads. The formation and dissociation processes of THF hydrate are observed using magnetic resonance imaging (MRI) technology.
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