[Stoves] Fly ash cement and of levels of radioactivity?

[Crispin Pemberton-Pigott]

Dear Biomass burners

 

There is a good article from sensible researchers  here

http://www.mindfully.org/Air/Mercury-Smoke-Biomass.htm

 

Now consider this and see how it affects your understanding of mercury in the environment (it is literally everywhere so pay attention).

 

Mercury is released disproportionally from biomass relative to the mass percent burned. In other words, operating a TLUD gasifier releases the mercury in largely gaseous form (95%) and the rest in particulate form. It is easily evaporated going from Hg+2 to Hgo. 

 

So should we worry about TLUD’s releasing, proportionally, about double the amount of Hg per useful MegaJoule of heat?

 

Hg is concentrated in the leaves, especially deciduous tree leaves. There are being processed into briquettes on an increasing scale. Basically all the Hg is released when they are burned even if there is char powder in the ash at the end.  Should we worry Richard and his alternative fuels promotion?

 

The most ‘toxic, mercury laden’ smoke in the stove community would come from a TLUD burning leaves from a deciduous tree while making biochar: full release, maximum concentration, least dilution during combustion.

 

Is everyone automatically alarmed? But TLUD’s and gasification and biochar and burning non-woody biomass are four of the darlings of the improved stove community. What now?

 

The answer is obviously to calculate what the emission rates are and the exposure level and the effect of such exposure before jumping to any conclusions about wood or leaves or coal or anything else.  Data matters. Coal is just old wood.  

 

Burn hot, maintain a cool head.

Crispin

 

++++++

 

One sandwich a week?

 

Who told you that?

 

Good grief. There is lots of mercury in the environment including in sea air, and there are completely unknown biological pathways metabolising it as was shown by the atmospheric research station at Cape Point. The general idea is that mercury is well "mixed in the atmosphere". Not so. Sometimes it drops to zero in the air blowing from Antarctica for hours at a time. There is no known process that can do this. Most atmospheric mercury is from the sea. 

 

I am amazed that these coal memes survive for so long. There is a really good lab at Clarkson Univ in Potsdam‎ NY that researches Hg in fish in the Great Lakes. Fantastically small quantities can be detected. One sandwich a week?  

 

Argh

Crispin 

 

 

Frans and Crispin,

Thanks for putting dimensions on the issue. I know that coal ash is the bad actor. 

I'm still perturbed that I can only eat one tuna fish sandwich a week because of the Mercury from coal. 

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