Crispin (or others) can you clarify this a little more - do the Glaser-Steiner wood gasifier and BBQ charcoals test high for PAHs because of post-manufacture additives? With BBQ charcoal, that could be lighter fluid, which could be naptha (-lene)?
Also, they reference an EPA method for PAH determination. Would that involve some kind of solvent extraction? If so is it an environmentally relevant analytical method? I assume folks have seen this paper: http://www.ncbi.nlm.nih.gov/pubmed/22321025 suggesting leaching of PAHs and dioxins from biochars should not constitute an environmental problem. Thoughts? JK On Wed, Feb 6, 2013 at 2:35 PM, Crispin Pemberton-Pigott < [email protected]> wrote: > Dear Tom**** > > ** ** > > Thanks for that:**** > > ** ** > > http://www.bacatec.de/dl/Ge09_Glaser-Steiner_engl.pdf**** > > ** ** > > “A further criterion for the quality of biochar is the lack of > contamination with both inorganic**** > > (e.g. heavy metals) and organic contaminants (e.g. polycyclic aromatic > hydrocarbons (PAH),**** > > dioxins etc.). In this study, we could only evaluate polycyclic aromatic > hydrocarbons (PAH,**** > > Fig. 4). Although chars from wood gasification are within the elemental > composition and the**** > > black carbon thresholds, they exhibit extremely high PAH contents (Fig. > 4). Therefore, they**** > > are not suited for soil amendment and thus, they cannot be classified as > biochar. Surprisingly**** > > high PAH contents were also measured in the barbeque charcoals (Fig. 4) > while all other**** > > investigated chars had low PAH contents (Fig. 4).”**** > > ** ** > > Well, there’s a kick in the head. Why not? Because of chemicals > manufactured in the process that were not there in the original fuel. That > may explain a lot to some experimenters.**** > > ** ** > > Regards**** > > Crispin**** > > _______________________________________________ > Stoves mailing list > > to Send a Message to the list, use the email address > [email protected] > > to UNSUBSCRIBE or Change your List Settings use the web page > > http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org > > for more Biomass Cooking Stoves, News and Information see our web site: > http://www.bioenergylists.org/ > > > -- Josh Kearns PhD Candidate, Environmental Engineering University of Colorado-Boulder Visiting Researcher, North Carolina State University Director of Science Aqueous Solutions www.aqsolutions.org Mobile: 720 989 3959 Skype: joshkearns
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