Environmental Engineering Reference
In-Depth Information
9 Carbon Capture
and Sequestration
You cannot get through a single day without having an impact on the world around
you—for better or for worse. What you do makes a difference.
—Jane Goodall
Human activities, especially the burning of fossil fuels such as coal, oil, and gas, have
caused a substantial increase in the concentration of carbon dioxide (CO 2 ) in the atmo-
sphere. This increase in atmospheric CO 2 —from about 280 to more than 380 parts
per million (ppm) over the last 250 years—is causing measureable global warming.
Potential adverse impacts include sea-level rise; increased frequency and intensity of
wildfires, floods, droughts, and tropical storms; changes in the amount, timing, and
distribution of rain, snow, and runoff; and disturbance of coastal marine and other eco-
systems. Rising atmospheric CO 2 is also increasing the absorption of CO 2 by seawater,
causing the ocean to become more acidic, with potentially disruptive effects on marine
plankton and coral reefs. Technically and economically feasible strategies are needed
to mitigate the consequences of increased atmospheric CO 2 .
USGS (2008)
Above all we should, in the century since Darwin, have come to know that man, while
captain of the adventuring ship, is hardly the sole object of its quest, and that his prior
assumptions to this effect arose from the simple necessity of whistling in the dark.
These things, I say, should have come to us. I fear they have not come to many.
—Aldo Leopold ( A Sand County Almanac, and Sketches Here and There , 1948)
INTRODUCTION TO CARBON CAPTURE AND SEQUESTRATION
The reader might wonder what carbon capture and sequestration (CCS) might have
to do with the environmental impacts of renewable energy. Renewable energy has
two pluses: (1) it is a possible source of energy now and in the future (it is renewable
and sustainable) and will be called on to replace nonrenewable hydrocarbon energy
sources as they are depleted; and (2) renewable energy produces little or no waste
products such as carbon dioxide or other chemical pollutants, so it has minimal
impact on the environment. It is the latter of these two pluses that is related to carbon
capture and sequestration. That is, at the present time and in the near future we have
(and will continue to have) an ongoing increase in atmospheric carbon dioxide. Many
scientists agree that global climate change is occurring and that to prevent its most
serious effects we must begin immediately to significantly reduce our greenhouse
gas (GHG) emissions. One major contributor to climate change is the release of the
greenhouse gas carbon dioxide (CO 2 ). This is the essence of the carbon capture and
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