[TheForge] microwave heavy metal session

[Andy Vida]

Bill & Kirsten wrote:

>    Steel is a blend of iron and carbon made by heating iron oxide to over
> 1000�C in the presence of coke and reducing agents.  Blast furnaces waste
> vast amounts of energy heating up the surrounding air.  Microwaves however,
> heat up polarised iron oxide, but not neutral molecules such as nitrogen,
> which make up almost 80 per cent of air."

	Meritorious idea, but there is at least one error.  The
	surrounding environment will still be heated due to thermal
	radiation from the melt, so saying that the air won't heat
	is not correct.  I would think, though, that this method 
	would prove far more efficient than certain types of furnaces.

	Bet the time to melt is shorter, too.
	
	One question though: doesn't a blast furnace need the air
	blast to oxidize away some of the impurities, or is the
	blast solely for obtaining temperature?  If the latter, then
	even that would be far more efficient without so much heat
	going up the flue.

	I'm surprised this hasn't been thought of a long time ago.