Environmental Engineering Reference
In-Depth Information
Figure 4.1.2 Coal-fi red power plant with post-combustion carbon capture
This animation can be viewed at : http://www.worldscientifi c.com/worldscibooks/
10.1142/p911#t=suppl
Question 4.1.1 Power plants
What is the most effi cient power plant in the USA and the rest of the word?
What is the average effi ciency of a USA power plant? Explain the differences.
Post-combustion is not the only way to approach carbon capture. If
one were willing to build an entirely new power plant, it may be possible
to fi nd more economical solutions using pre-combustion carbon capture.
The idea behind pre-combustion carbon capture is essentially to burn
coal with pure oxygen rather than air, which contains a mix of several
gasses. The resulting fl ue gas would only contain water and carbon diox-
ide. Then, by condensing the water, we could easily separate CO 2 from
the gas mixture. Burning coal with pure oxygen, however, means we
have to fi nd a way to effi ciently separate oxygen from air. At present, this
step is done using cryogenic separations, which are expensive and
energy-intensive processes. So for pre-combustion methods the cost of
CO 2 separation is mainly associated with the air separation step.
Additional research is needed to fi nd or develop materials that can
accomplish this separation more effi ciently.
Search WWH ::




Custom Search