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Feasibility of Large-Scale Ocean CO2 Sequestration

Description: This report covers research accomplished during CY 2006 under a modification of a previous award. During this period we completed analysis of the acoustic detection and modeling of a rising deep-sea liquid CO{sub 2} plume, and published the results in a major journal. The results are applicable to detection of leakage of CO{sub 2} from the sea floor, either from natural CO{sub 2} vents, or from purposefully disposed CO{sub 2} in sub-sea geologic formations. In April 2006 we executed, in collaboration with colleagues from Massachusetts Institute of Technology, Oak Ridge National Laboratory, and Canada a novel at sea experiment on the creation of a sinking plume of a CO{sub 2} hydrate composite paste, extruded through nozzles designed by ORNL. The work showed that a sinking, and slowly dissolving, mass can be created at depths where the pure liquid (above) would rise far and fast. In August 2006 we executed a cruise to the massive exposed methane hydrates in Barkley Canyon, off-shore Vancouver Island. There we cored the exposed hydrates, and exposed the specimens on the sea floor at 850m depth to liquid CO{sub 2} in a 3 liter closed container. The object was to examine possible inter-conversion of methane hydrate to CO{sub 2} hydrate with liberation of methane gas, and sequestration of the CO{sub 2} as a solid. Each of these complex experiments was successfully executed and the results reported in major journals and/or at national meetings.
Date: September 30, 2006
Creator: Brewer, Peter G.
Partner: UNT Libraries Government Documents Department

Feasibility of Large-Scale Ocean CO2 Sequestration

Description: Scientific knowledge of natural clathrate hydrates has grown enormously over the past decade, with spectacular new findings of large exposures of complex hydrates on the sea floor, the development of new tools for examining the solid phase in situ, significant progress in modeling natural hydrate systems, and the discovery of exotic hydrates associated with sea floor venting of liquid CO{sub 2}. Major unresolved questions remain about the role of hydrates in response to climate change today, and correlations between the hydrate reservoir of Earth and the stable isotopic evidence of massive hydrate dissociation in the geologic past. The examination of hydrates as a possible energy resource is proceeding apace for the subpermafrost accumulations in the Arctic, but serious questions remain about the viability of marine hydrates as an economic resource. New and energetic explorations by nations such as India and China are quickly uncovering large hydrate findings on their continental shelves. In this report we detail research carried out in the period October 1, 2007 through September 30, 2008. The primary body of work is contained in a formal publication attached as Appendix 1 to this report. In brief we have surveyed the recent literature with respect to the natural occurrence of clathrate hydrates (with a special emphasis on methane hydrates), the tools used to investigate them and their potential as a new source of natural gas for energy production.
Date: August 31, 2008
Creator: Brewer, Peter
Partner: UNT Libraries Government Documents Department

FEASIBILITY OF LARGE-SCALE OCEAN CO2 SEQUESTRATION

Description: The past year has been one of continued high productivity and technical innovation for research conducted under support of this contract. We report here on the successful completion of development of a deep-ocean laser Raman spectrometer, and the use of this novel system for direct in situ measurement of the dissolution rate of CO{sub 2} from a N{sub 2}/CO{sub 2} gas mixture at 300m ocean depth. We have carried out the deepest ever ocean CO{sub 2} injection experiment at 3960m depth, and have observed the behavior of the plume of low pH/high CO{sub 2} water emanating from this source. This was made possible by the design, construction, and operation of a novel flume to contain the liquid CO{sub 2} and to force flow in a controlled manner over the liquid CO{sub 2} surface. In carrying out this experiment we observed for the first time the extraordinarily rapid hydration kinetics of CO{sub 2} with water at high pressure. This initial observation was later confirmed in a carefully controlled series of acid and CO{sub 2} injection studies at varying depths. In carrying out this research we are aware of the environmental concerns, and we have been in the forefront of identifying the challenges resulting from the far greater quantities of CO{sub 2} being passively absorbed from the atmosphere. This quantity now is approximately 1 million metric tons CO{sub 2} per hour, and reasonable projections for the 21st century project ocean pH changes of 0.3 or more by mid-century. The PIs have played a key role in organizing a major international meeting on this topic, and on reporting the results. We are now engaged in developing the novel techniques required to investigate this problem.
Date: December 1, 2004
Creator: Brewer, Peter G. & Barry, James
Partner: UNT Libraries Government Documents Department

FEASIBILITY OF LARGE-SCALE OCEAN CO2 SEQUESTRATION

Description: This report describes research conducted between July 1, 2003 and September 30, 2003 on the use of dry regenerable sorbents for concentration of carbon dioxide from flue gas. Based on 5-cycle fixed bed tests of grade 3 sodium bicarbonate, calcination in carbon dioxide at 160 C does not affect the activity or capacity of the sorbent in subsequent carbonation cycles. Increasing the calcination temperature to 200 C does have an adverse impact on sorbent performance. RTI produced a supported sorbent with a nominal composition of 40% sodium carbonate. While this material has good attrition resistance, the activity, as determined by thermogravimetry, fixed bed testing and analysis of physical properties is insufficient for use as a carbon dioxide sorbent.
Date: December 16, 2003
Creator: Brewer, Peter & Barry, James
Partner: UNT Libraries Government Documents Department

Feasibility of Large-Scale Ocean CO2 Sequestration

Description: Direct ocean injection of CO{sub 2} is one of several approaches under consideration to sequester carbon dioxide in order to stabilize atmospheric CO{sub 2} near 550 ppm (2X preindustrial CO{sub 2} levels). Without significant efforts to stabilize greenhouse gas emissions, the Earth is expected to experience extreme climate warming consequences associated with the projected high ({approx}3-4X preindustrial) atmospheric CO{sub 2} levels in the next 100 to 200 years. Research funded by DOE-Office of Fossil Energy under this award is based on the development of novel experimental methods by MBARI to deploy small quantities (5-45 l) of liquid CO{sub 2} in the deep-sea for the purposes of investigating the fundamental science underlying the concepts of ocean CO{sub 2} sequestration. This project is linked closely with studies funded by the Office of Science and the Monterey Bay Aquarium Research Institute (MBARI). The objectives of studies in marine chemistry funded by the Office of Fossil Energy and MBARI are to: (1) Determine the long term fate of CO{sub 2} hydrate in the deep-sea, (2) Investigate the geochemical changes in marine sediments and pore waters associated with CO{sub 2} disposal, and (3) Investigate the transfer of CO{sub 2} from the hydrate phase to the oceanic water column as a boundary condition for ocean modeling of the fate of the released material. These activities extend the results of recent studies using the deep-sea CO{sub 2} deployment system, which characterized several features of liquid CO{sub 2} released into the sea, including hydrate formation and factors influencing dissolution rates of CO{sub 2}. Results from this project are relevant in determining the efficacy of carbon sequestration and the degree of perturbation of seawater chemistry. Biological studies, funded jointly by the Office of Science, Office of Fossil Energy, and MBARI, focus on the environmental consequences of CO{sub 2} release ...
Date: September 30, 2001
Creator: Brewer, Peter & Barry, James
Partner: UNT Libraries Government Documents Department

Feasibility of Large-Scale Ocean CO2 Sequestration

Description: The project accomplishments in 2005 have been exceptional, and have seen radical new techniques successfully devised and implemented. At the outset the goal set was to create a system dubbed FOCE--Free Ocean CO{sub 2} Enrichment--for investigating the impact of rapidly growing ocean CO{sub 2} levels from passive absorption by the surface ocean. A paper describing progress in this area is included with this report. On June 29, 2005 the P.I. presented a seminar on this work at NETL, and after discussion with Program Officers it was suggested that a return to the original project focus of investigating direct disposal techniques, rather than passive disposal effects, should be undertaken. This suggestion was rapidly acted upon, and in November 2005 a major field breakthrough was accomplished in collaboration with colleagues from NETL, MIT, and AIST (Japan). In this effort the real time three-dimensional acoustic detection of a freely released small-scale CO{sub 2} plume was accomplished. In addition we have successfully field tested the theoretical model of Zeebe and Wolf-Gladrow for CO{sub 2} system kinetics at depth, thus leading to more accurate prediction of the local pH perturbations of a CO{sub 2} plume.
Date: December 1, 2005
Creator: Brewer, Peter G. & Barry, James
Partner: UNT Libraries Government Documents Department

Final Progress Report: Direct Experiments on the Ocean Disposal of Fossil Fuel CO2.

Description: OAK-B135 This report summarizes activities and results of investigations of the potential environmental consequences of direct injection of carbon dioxide into the deep-sea as a carbon sequestration method. Results of field experiments using small scale in situ releases of liquid CO2 are described in detail. The major conclusions of these experiments are that mortality rates of deep sea biota will vary depending on the concentrations of CO2 in deep ocean waters that result from a carbon sequestration project. Large changes in seawater acidity and carbon dioxide content near CO2 release sites will likely cause significant harm to deep-sea marine life. Smaller changes in seawater chemistry at greater distances from release sites will be less harmful, but may result in significant ecosystem changes.
Date: May 25, 2004
Creator: Barry, James P. & Brewer, Peter G.
Partner: UNT Libraries Government Documents Department