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Old 01-May-2008, 01:33 PM
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Quote:
Originally Posted by neilzero View Post
It is important to remove polutants before waste gases are released into our atmosphere. I don't think any of the above mentioned processes are suitable for cleaning polutants from air when the polutants are a few parts per million. Slacked lime = Ca(OH)2 will absorb some these polutants, but then we are stuck with mountains of poluted lime. Worse the slacked lime is presently made from limestone and the carbon dioxide is released into our atmosphere. I presume the hot carbon dioxide can be removed from new design lime kilns at considerable cost, but this is not often done at present. Neil
If all you want to do is remove the CO2 from the flue gases (but keep it as CO2), you would probably use the amine process I discussed above. The amine is recycled, the only significant cost/waste is the energy you have to spend, which in effect decreases the energy output of your powerplant.

Of course now you have CO2 gas, and the question becomes what you do with it. The suggestions I have seen are not to convert it to calcium carbonate, but to store it as a gas, in geological formations, for example.
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