The problem is that carbon-capture-and-sequestration (CCS) adds to the expense of using coal. Expectations that it might pay for itself by enhancing oil field recovery or pushing up coal bed methane may or may not pay off. Which is why research like this is welcome.
In a related story to be covered here next week, major oil companies have cancelled plans for CO2 sesquestration/enhanced recovery projects, raising more questions about the dream-technology's viability.
Feds: Storing Carbon Dioxide Underground Can Work
Andrea Thompson, June 26, 2007 (LiveScience via Yahoo News)
Researchers, U.S. Department of Energy (DOE)’s National Energy Technology Laboratory (NETL)
one version of sequestration (click to enlarge)
Research into sequestration of carbon dioxide and other greenhouse gas (GHG) emissions in coal bed seams and oil wells, the “storage” part of the phrase commonly used to define the processing of “clean” coal, “carbon capture and storage.”
Field projects testing the “geologic” sequestration of GHG emissions are ongoing asare these controlled environment studies.
NETL has offices in Pittsburgh, PA, Tulsa, OK, Albany, OR, Morgantown, WV, and Fairbanks, AK. The geologic sequestration project seems to be out of the Pittsburgh office.
- Geologic sequestration of GHG emissions like CO2 in coal beds would release coal bed methane for use as a fuel. Pumping the GHGs into oil wells would enhance the well’s production. Both coal beds and oil wells are hypothesized to be safe sequestration sites.
- NETL researchers have constructed a controlled environment mimicking pressures, temperatures and other factors of geologic sequestration to better evaluate the idea. Another recent study found sequestration effective but observed that toxic metals released in the process could contaminate ground water.
- World geologic sequestration capacity, if possible ground water contamination does not eliminate potential sites (A BIG IF), is estimated at 3 trillion tons.
and another (click to enlarge)
Reserchers: “Changes in water chemistry and the potential for mobilizing toxic trace elements from coal beds are potentially important factors to be considered when evaluating deep, unmineable coal seams for CO2 sequestration, though it is also possible that, considering the depth of the injection, that such effects might be harmless…”