Abstract
The onset of gas hydrate nucleation is greatly affected by the thermal history of the water that forms its lattice structure. Hydrate formation experiments were performed in a 72 L pressure vessel by injecting bubbles of carbon dioxide through a 1 L tube at hydrate formation pressures (1.4 to 3.7 MPa) and temperatures (2 to 5 °C). The results revealed that when even a small fraction (e.g., 5-35%) of the water in which the hydrate formed was recently thawed the overpressure for nucleation was reduced by an average of 50% as compared to untreated distilled water. This observation was confirmed by an analysis of variance (ANOVA) test that indicated that recently thawed water required a significantly lower overpressure compared to the untreated distilled water. In experiments where hydrate nucleated at low overpressure (e.g., 0.75 MPa), hydrate formed at the vapor-liquid interface, encrusting the bubbles with less than 1 g of hydrate accumulation in the first minute. When a higher overpressure was required for nucleation (e.g., 1.3 MPa), hydrate was observed to form abruptly not only on bubbles but also from the bulk liquid phase, typically accumulating a mass of more than 100 g in the first few seconds. Our results show that initiation of hydrate formation is strongly influenced by temperature-dependent pre-structuring of water molecules prior to their contact with gas. Although as little as a 5% volume fraction of pre-structured water may decrease the required overpressure, once hydrate formation commences the mass of hydrate accumulation is dependent on the overpressure.
© 2015 by Walter de Gruyter Berlin/Boston
Articles in the same Issue
- Introductory overview: Hydrate knowledge development
- Scanning Electron Microscopy investigations of laboratory-grown gas clathrate hydrates formed from melting ice, and comparison to natural hydrates
- Dynamics of trimethylene oxide in a structure II clathrate hydrate
- The stability of methane hydrates in highly concentrated electrolyte solutions by differential scanning calorimetry and theoretical computation
- The effect of elevated methane pressure on methane hydrate dissociation
- Methane hydrate formation in partially water-saturated Ottawa sand
- Methanol—inhibitor or promoter of the formation of gas hydrates from deuterated ice?
- Investigating the performance of clathrate hydrate inhibitors using in situ Raman spectroscopy and differential scanning calorimetry
- Physical properties and rock physics models of sediment containing natural and laboratory-formed methane gas hydrate
- Experimental studies on the formation of porous gas hydrates
- Investigation of jet breakup and droplet size distribution of liquid CO2and water systems—implications for CO2hydrate formation for ocean carbon sequestration
- Measurement of clathrate hydrate precipitation from CO2solution by a nondestructive method
- Influence of water thermal history and overpressure on CO2-hydrate nucleation and morphology
- Growth-controlling processes of CO2gas hydrates
- Thermodynamic prediction of clathrate hydrate dissociation conditions in mesoporous media
- Modeling dynamic marine gas hydrate systems
- Late-stage, high-temperature processesing in the Allende meteorite: Record from Ca,Fe-rich silicate rims around dark inclusions
- Partitioning of Sr, Ba, Rb, Y, and LREE between alkali feldspar and peraluminous silicic magma
- Nondestructive three-dimensional element-concentration mapping of a Cs-doped partially molten granite by X-ray computed tomography using synchrotron radiation
- A theoretical study of structural factors correlated with 23Na NMR parameters
- Metamorphic formation of Sr-apatite and Sr-bearing monazite in a high-pressure rock from the Bohemian Massif
- Ultra-deep origin of garnet peridotite from the North Qaidam ultrahigh-pressure belt, Northern Tibetan Plateau, NW China
- Letter. Novel high-pressure behavior in chlorite: A synchrotron XRD study of clinochlore to 27 GPa
- Letter. Periodic precipitation pattern formation in hydrothermally treated metamict zircon
- A high pressure X-ray diffraction study of aragonite and the post-aragonite phase transition in CaCO3
Articles in the same Issue
- Introductory overview: Hydrate knowledge development
- Scanning Electron Microscopy investigations of laboratory-grown gas clathrate hydrates formed from melting ice, and comparison to natural hydrates
- Dynamics of trimethylene oxide in a structure II clathrate hydrate
- The stability of methane hydrates in highly concentrated electrolyte solutions by differential scanning calorimetry and theoretical computation
- The effect of elevated methane pressure on methane hydrate dissociation
- Methane hydrate formation in partially water-saturated Ottawa sand
- Methanol—inhibitor or promoter of the formation of gas hydrates from deuterated ice?
- Investigating the performance of clathrate hydrate inhibitors using in situ Raman spectroscopy and differential scanning calorimetry
- Physical properties and rock physics models of sediment containing natural and laboratory-formed methane gas hydrate
- Experimental studies on the formation of porous gas hydrates
- Investigation of jet breakup and droplet size distribution of liquid CO2and water systems—implications for CO2hydrate formation for ocean carbon sequestration
- Measurement of clathrate hydrate precipitation from CO2solution by a nondestructive method
- Influence of water thermal history and overpressure on CO2-hydrate nucleation and morphology
- Growth-controlling processes of CO2gas hydrates
- Thermodynamic prediction of clathrate hydrate dissociation conditions in mesoporous media
- Modeling dynamic marine gas hydrate systems
- Late-stage, high-temperature processesing in the Allende meteorite: Record from Ca,Fe-rich silicate rims around dark inclusions
- Partitioning of Sr, Ba, Rb, Y, and LREE between alkali feldspar and peraluminous silicic magma
- Nondestructive three-dimensional element-concentration mapping of a Cs-doped partially molten granite by X-ray computed tomography using synchrotron radiation
- A theoretical study of structural factors correlated with 23Na NMR parameters
- Metamorphic formation of Sr-apatite and Sr-bearing monazite in a high-pressure rock from the Bohemian Massif
- Ultra-deep origin of garnet peridotite from the North Qaidam ultrahigh-pressure belt, Northern Tibetan Plateau, NW China
- Letter. Novel high-pressure behavior in chlorite: A synchrotron XRD study of clinochlore to 27 GPa
- Letter. Periodic precipitation pattern formation in hydrothermally treated metamict zircon
- A high pressure X-ray diffraction study of aragonite and the post-aragonite phase transition in CaCO3