clot wrote: ...
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Again, the inorganic Hg isn't the issue--the problem is, it doesn't stay that way in the environment always -- it gets methylated which is how it hurts.
Don't know about in the UK specifically, but the current technology in place in the US is estimated to capture only a little over a third of total estimated emissions. This will go up as more wet scrubbers come on line and as other control/abatement technology techniques are implemented.
It's a very complicated area as higher levels of Hg capture are observed for bituminous coal-fired plants as compared to low-rank coal-fired plants, Hg capture varies drastically across existing plants, higher levels of Hg capture are observed in fabric filters (FF) compared to electrostatic precipitators (ESPs), and a significant capture of Hg2+ in wet SO2 scrubbers.
As just one example, the above observation about bituminous coal compared to the low-rank coals is owing in large part to the increased Cl content of the bituminous coals which tend to produce Hg(2+) compounds which are much more amenable to adsorption in ESPs than Hg(0) compounds.
(Spent about 30 years working w/ electric utilities, about the last 20 w/ fossil...)
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