Re: FW: "Waste" Gypsum Could Help Boost Crop Yields
Bob MacGregor (rdmacgregor@gov.pe.ca)
Fri, 28 May 1999 11:01:33 -0400
I remember reading years ago that more people die from radiation-induced cancers from coal burning residue than from nuclear power (I can imagine who promulgated this information!). Anyway, I also heard that in the 50's lignite coal in North Dakota was burned specifically as a means of creating a uranium "ore" -- ie, the resulting ash. SO, the moral of the story is that stuff left over from coal burning power plants needs careful analysis before it is converted to another use (sort of like sewage sludge, eh?).
Theoretically, reasonably "pure" gypsum can be produced. The bottom ash and "clinker" stays put; the fly ash is (nearly all) removed by cyclonic separation and electrostatic precipitators, physical barriers etc.; and, finally, the volatile gases are "scrubbed" with crushed limestone and water. Of course, while sulfur oxides are the main gaseous contaminants, there are a lot of other elements that are volatilized (ie, not particulates susceptible to electrostatic precipitation) and sent up the stacks -- these can include heavy metals which could be trapped in the scrubbing process.
I wonder who is doing the appropriate testing (if anyone) prior to land application?
BOB
To Unsubscribe: Email majordomo@ces.ncsu.edu with the command
"unsubscribe sanet-mg". If you receive the digest format, use the command
"unsubscribe sanet-mg-digest".
To Subscribe to Digest: Email majordomo@ces.ncsu.edu with the command
"subscribe sanet-mg-digest".
All messages to sanet-mg are archived at:
http://www.sare.org/htdocs/hypermail