Measurements of mechanical properties of the liquid CO2-water-CO2-hydrate system

Uchida, Tsutomu; Kawabata, Junichi

doi:10.1016/s0360-5442(96)00112-0

Cited by 42 publications

(36 citation statements)

References 8 publications

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“…Figure 4 shows that the heat release into the guest‐fluid phase almost vanishes within one minute and that the further film growth is exclusively sustained by the heat transfer into the film. These predictions are not in good agreement with existing experimental results indicating a hydrate‐film thickness of the order of 10 μm 7,8. This inconsistency between the predictions and the experimental results indicates that some mechanism, other than the heat removal, dominates the rate of hydrate formation.…”

Section: Resultscontrasting

confidence: 76%

Numerical Simulation of Transient Heat and Mass Transfer Controlling the Growth of a Hydrate Film

Mochizuki¹,

Mori²

2000

Annals of the New York Academy of Sciences

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Section: Resultscontrasting

confidence: 76%

Numerical Simulation of Transient Heat and Mass Transfer Controlling the Growth of a Hydrate Film

Mochizuki¹,

Mori²

2000

Annals of the New York Academy of Sciences

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“…The change in the hydrate thickness on a CO2 droplet results from hydrate growth and dissolution, which are controlled by mass transfer from liquid CO2 into water depending on the saturation state of CO2 in water (20,31,34). For the case in which a liquid CO2 droplet is surrounded by water, a mass transfer model has shown that the hydrate shell greatly reduces the mass transfer of CO2 into water (19,28,35). The rate of change of the hydrate shell is limited by mass transfer, expressed as dr/dt ) k*, where r is the radius of the drop and k* is the overall mass transfer coefficient (19).…”

Section: Resultsmentioning

confidence: 99%

“…Accordingly, k* is the overall mass transfer coefficient across the hydrate film. Combining eqs 4-6, one derives or The latter expression (eq 9) is obtained because the thickness of the hydrate shell, ∆r, is normally on the order of 1-10 µm (31,34,35), making ∆r/r 0 < 1/20.…”

Section: Resultsmentioning

confidence: 99%

CO₂ Hydrate Composite for Ocean Carbon Sequestration

Lee

Liang

Riestenberg

et al. 2003

Environ. Sci. Technol.

126

105

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Rapid CO2 hydrate formation was investigated with the objective of producing a negatively buoyant CO2-seawater mixture under high-pressure and low-temperature conditions, simulating direct CO2 injection at intermediate ocean depths of 1.0-1.3 km. A coflow reactor was developed to maximize CO2 hydrate production by injecting water droplets (e.g., approximately 267 microm average diameter) from a capillary tube into liquid CO2. The droplets were injected in the mixing zone of the reactor where CO2 hydrate formed at the surface of the water droplets. The water-encased hydrate particles aggregated in the liquid CO2, producing a paste-like composite containing CO2 hydrate, liquid CO2, and water phases. This composite was extruded into ambient water from the coflow reactor as a coherent cylindrical mass, approximately 6 mm in diameter, which broke into pieces 5-10 cm long. Both modeling and experiments demonstrated that conversion from liquid CO2 to CO2 hydrate increased with water flow rate, ambient pressure, and residence time and decreased with CO2 flow rate. Increased mixing intensity, as expressed by the Reynolds number, enhanced the mass transfer and increased the conversion of liquid CO2 into CO2 hydrate. Using a plume model, we show that hydrate composite particles (for a CO2 loading of 1000 kg/s and 0.25 hydrate conversion) will dissolve and sink through a total depth of 350 m. This suggests significantly better CO2 dispersal and potentially reduced environmental impacts than would be possible by simply discharging positively buoyant liquid CO2 droplets. Further studies are needed to address hydrate conversion efficiency, scale-up criteria, sequestration longevity, and impact on the ocean biota before in-situ production of sinking CO2 hydrate composite can be applied to oceanic CO2 storage and sequestration.

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“…29 The SMD/D SM correlated well with the Weber number for each mixer; the SMD decreased with increasing Weber number, or equivalently the water flow velocity. It is known that the SMD/D SM of the drops formed in Kenics static mixers from liquid-liquid flows are well correlated with the Weber number.…”

mentioning

confidence: 80%

An analysis of liquid CO₂ drop formation with and without hydrate formation in static mixers

et al. 2010

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The formation process of CO 2 drops in various types of Kenics Static Mixers was analyzed from the perspective of energy dissipation in the mixer, focusing on the formation of drop surfaces. Experimental studies on CO 2 drop formation were conducted under varying temperatures, pressure, and flow rates, with and without hydrate formation. Analysis of the CO 2 drop size and distribution at several locations within the static mixer was conducted, as of pressure drop in the mixer, to determine dissipation energies. In all the experimental conditions, by considering the surface energy for hydrate formation, the energy required for the formation of CO 2 drops correlated well with total energy dissipation by mixer flow, which is represented by a pressure drop along the mixer. This process has important applications to the formation of liquid CO 2 for ocean disposal as a countermeasure to global warming.

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Measurements of mechanical properties of the liquid CO2-water-CO2-hydrate system

Cited by 42 publications

References 8 publications

Numerical Simulation of Transient Heat and Mass Transfer Controlling the Growth of a Hydrate Film

Numerical Simulation of Transient Heat and Mass Transfer Controlling the Growth of a Hydrate Film

CO₂ Hydrate Composite for Ocean Carbon Sequestration

An analysis of liquid CO₂ drop formation with and without hydrate formation in static mixers

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Measurements of mechanical properties of the liquid CO2-water-CO2-hydrate system

Cited by 42 publications

References 8 publications

Numerical Simulation of Transient Heat and Mass Transfer Controlling the Growth of a Hydrate Film

Numerical Simulation of Transient Heat and Mass Transfer Controlling the Growth of a Hydrate Film

CO2 Hydrate Composite for Ocean Carbon Sequestration

An analysis of liquid CO2 drop formation with and without hydrate formation in static mixers

Contact Info

Product

Resources

About

CO₂ Hydrate Composite for Ocean Carbon Sequestration

An analysis of liquid CO₂ drop formation with and without hydrate formation in static mixers