Field studies on the formation of sinking CO2 particles for ocean carbon sequestration: effects of injector geometry on particle density and dissolution rate and model simulation of plume behavior.
We have carried out the second phase of field studies to determine the effectiveness of a coflow injector which mixes liquid CO2 and ambient seawater to produce a hydrate slurry as a possible CO2 delivery method for ocean carbon sequestration. The experiments were carried out at ocean depths of 1000-1300 m in Monterey Bay, CA, using a larger injector than that initially employed under remotely operated vehicle control and imaging of the product. Solidlike composite particles comprised of water, solid CO2 hydrate, and liquid CO2 were produced in both studies. In the recent injections, the particles consistently sank at rates of approximately 5 cm s(-1). The density of the sinking particles suggested that approximately 40% of the injected CO2 was converted to hydrate, while image analysis of the particle shrinking rate indicated a CO2 dissolution rate of 0.76-1.29 micromol cm(-2) s(-1). Plume modeling of the hydrate composite particles suggests that while discrete particles may sink 10-70 m, injections with CO2 mass fluxes of 1-1000 kg s(-1) would result in sinking plumes 120-1000 m belowthe injection point.
Riestenberg
David E
DE
Oak Ridge National Laboratory, Post Office Box 2008, Oak Ridge, Tennessee 37831, USA.
Tsouris
Costas
C
Brewer
Peter G
PG
Peltzer
Edward T
ET
Walz
Peter
P
Chow
Aaron C
AC
Adams
E Eric
EE
D002244:Carbon / Q000032:analysis / Q000737:chemistry*; D002245:Carbon Dioxide / Q000032:analysis* / Q000737:chemistry; D004784:Environmental Monitoring / Q000379:methods*; D006863:Hydrogen-Ion Concentration; D007091:Image Processing, Computer-Assisted; D008962:Models, Theoretical; D009584:Nitrogen / Q000032:analysis; D012623:Seawater / Q000737:chemistry*; D012995:Solubility; D013997:Time Factors
D002245:Carbon Dioxide; D002244:Carbon; D009584:Nitrogen