Naked Science Forum

Non Life Sciences => Technology => Topic started by: CliffordK on 03/03/2013 08:44:38

Title: Can one use iron oxide to produce energy from coal without CO2?
Post by: CliffordK on 03/03/2013 08:44:38
I heard on the radio about a new process extracting energy from coal using iron oxide.  They seemed to indicate that they could "cleanly" extract energy without producing carbon dioxide.

http://www.foxnews.com/science/2013/02/20/coal-cleanest-energy-source-there-is/

They say the only byproducts are ash & water.

Isn't something missing?
Title: Re: Can one use iron oxide to produce energy from coal without CO2?
Post by: graham.d on 03/03/2013 10:43:30
The process is (as often the case) not reported well by Fox. The process is said to produce CO2 (by reducing the Iron Oxide) but basically just pure CO2 which is easy to extract. You get the same result by burning the coal in pure oxygen rather than air but this is costly. A better article is here...

http://www.technologyreview.com/news/510736/a-cleaner-way-to-use-coal/
Title: Re: Can one use iron oxide to produce energy from coal without CO2?
Post by: Bored chemist on 03/03/2013 10:45:12
Looks silly to me. The best they could hope for is that the CO2 is produced in a way that's easier to trap.
That still leaves the question of what to do with it.
Title: Re: Can one use iron oxide to produce energy from coal without CO2?
Post by: CliffordK on 03/03/2013 11:28:18
Thanks,
So the goal is to reduce NOX, and make it easier to capture the CO2.
That is, assuming that there is either a market for the CO2, for example selling it to greenhouses, or a method to store it, hopefully in a reversible fashion, if we should ever need it again in the future.  And, a couple of large power plants would quickly overwhelm the market for CO2.

I wonder what the overall efficiency of the process is.  One certainly wouldn't want to do something that would double the fuel requirements for the same energy production.

For heat generation, concentrated oxygen may be best, whereas for an internal combustion engine, a semi-inert gas for expansion may be beneficial.