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Updated: Aug 9, 2026
08:46
Methane Hydrate Crystallization on Sessile Water Droplets
Published on: May 26, 2021
Detecting gas hydrate behavior in crude oil using NMR
Shuqiang Gao1, Waylon House, Walter G Chapman
1Chemical Engineering Department, Rice University, Houston, Texas 77251, USA.
The Journal of Physical Chemistry. B
|March 31, 2006
Summary
Proton nuclear magnetic resonance (NMR) spectroscopy directly monitors natural gas hydrate formation in black oil. This rapid technique overcomes limitations of traditional pressure-based methods for improved flow assurance studies.
Area of Science:
- Petroleum Engineering
- Physical Chemistry
- Materials Science
Background:
- Natural gas hydrate behavior in black oil is critical for deep-water flow assurance but poorly understood.
- Traditional methods rely on indirect pressure changes, which are unreliable in viscous or low-water conditions.
Purpose of the Study:
- To develop a direct method for observing and quantifying natural gas hydrate formation in black oil emulsions.
- To overcome the limitations of indirect pressure-monitoring techniques.
Main Methods:
- Employing proton nuclear magnetic resonance (NMR) spectroscopy to directly observe the liquid-to-solid conversion of water.
- Utilizing the spectral distinction between water and black oil based on chemical shifts in high magnetic fields.
- Monitoring changes in the water peak area to measure hydrate conversion.
Main Results:
- Proton NMR spectroscopy directly measures water immobilization during hydrate formation.
- The technique distinguishes hydrate formation from simple solubility changes.
- Measurements are rapid (seconds) and accurate, providing reliable thermodynamic data.
Conclusions:
- Proton NMR spectroscopy offers a direct, rapid, and accurate method for studying natural gas hydrate behavior in black oil.
- This technique enhances understanding of flow assurance challenges in the petroleum industry.
- The method has potential applications in studying phase transitions in various emulsions.
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