[Terrapreta] FW: Simple charcoal kiln

[Peter Read]

Hi Sean

I just circulated Folke Gunter's message to the New Zealand Sustainable Energy Forum because it seemed to me to be pretty neat and to overcome just the problems with 'charcoal in a barrel' which you mention

If you study Folke's pictures you will see that the pyrolysis chamber is not a barrel. It is an upside-down retort inside a barrel, and done in such a way that the pyrolysis gases are emitted at the bottom of the barrel and are forced through the firezone where, with ample  air supply, any CH4 is combusted to CO2.

Re: "The problems are related to lack of control over inflows of oxidants (air/oxygen) and outflows of "producer gas" and lack of temperature controls." It seems to me that oxidant (air) supply is limited to the small amount that is trapped in the retort when it is turned upside down and the outflow of producer gas is controlled to flow through the firezone.  As regards temperature of pyrolysis that depends on the original fire around the retort and the quality of the 'producer gas' that is burned going through the fire, in turn related to the quality of the feedstock.  But I understand that this temperature can vary quite widely and still yield charcoal, and hence biochar, albeit of varying quality.

Clearly something more sophisticated is needed for consistent quality saleable product that Stephen and others aim for, but as a low transportation, negative emissions way of disposing of garden woody waste it seems better than the traditional bonfire?  Maybe Folke will comment.

Peter
  ----- Original Message ----- 
  From: Sean K. Barry 
  To: Tom Miles 
  Cc: terrapreta 
  Sent: Sunday, April 27, 2008 11:32 AM
  Subject: Re: [Terrapreta] FW: Simple charcoal kiln


  Hi Tom,

  I did note this.  Folke Gunthur does see and view many things about this issue very astutely and correctly, in my opinion.  However, "simple" "charcoal-in-a-barrel" kilns (or retorts), whatever whoever wants to call them, are not a great idea.  Simple is a great idea.  In a barrel is not.  I think there is ample evidence to support this.  The problems are as I stated; emissions of GHGs and efficiency are insufficient for the task.  I hope to be able to provide more data to support this, too, soon enough.

  There are plenty of people on this list;l Dr. Stephen Joseph, Adrianna Downey, Michael Bailles, Edward Someous, Michael Antal, and others, who I am sure would back me up on this position.  There are undoubtedly others, not on this list, who would also support this view.  My reading of these peoples work and my own work has already shown to me that very simple "charcoal-in-a-barrel" retorts cannot do what we need to do.

  It is not the simplicity of the operation or the fact that the "pyrolysis chamber" is itself a "barrel".  The problems are related to lack of control over inflows of oxidants (air/oxygen) and outflows of "producer gas" and lack of temperature controls.  Automatic (and hence simple), enclosed, non-polluting, self-controlled operations can be done with charcoal kilns made inside a barrel.  I am positive of this.  Making vast quantities of charcoal by pyrolyzing biomass, just cannot, in my opinion, be relegated to the use of large numbers of unregulated "simple" "charcoal-in-a-barrel" type retorts or kilns.  I probably need to say no more about this.

  Regards,

  SKB
    ----- Original Message ----- 
    From: Tom Miles 
    To: 'Sean K. Barry' 
    Sent: Saturday, April 26, 2008 5:30 PM
    Subject: RE: [Terrapreta] FW: Simple charcoal kiln


    Sean,

     

    Note that the original posting was from Folke Gunther. Erin just rescued it from a filter that thought it was SPAM.  

     

    Tom

     

     

    From: terrapreta-bounces at bioenergylists.org [mailto:terrapreta-bounces at bioenergylists.org] On Behalf Of Sean K. Barry
    Sent: Saturday, April 26, 2008 3:25 PM
    To: 'terrapreta'; Erin Rasmussen
    Subject: Re: [Terrapreta] FW: Simple charcoal kiln

     

    Dear Erin,

     

    Thank you for this posting.  Making charcoal simply is an objective of this group.  Making charcoal in a "retort" that is made from a couple of interleaved barrels is simple, yes.  But, it is somewhat inefficient, can only make small amounts of charcoal at a time, and it quite easily can vent more destructive green house gases (GHGs) to the atmosphere, than could ever be sequestered, even it all of the charcoal were buried.  This has been discussed here before.  The archives have plenty of references to "charcoal in a barrel" kilns.

     

    Although making some charcoal in this way, in order to study "charcoal-in-soil" applications, for instance, is not a problem per se, this is not the way we would want to make large amounts of charcoal for use in developing Terra Preta soils on a widespread basis.  Many in this group would believe, though, that to solve the problems of world food production and combat Global Climate Change, using the development of Terra Preta soils will require vast amounts of charcoal.  It would not be good to make vast amounts of charcoal in simple, polluting, inefficient charcoal in a barrel" retorts.

     

    Still, making charcoal can be much cleaner, more efficient and still simple.  It's just that this is not done in "open" or "semi-open"  barrels.

     

    Regards,

     

    SKB

      ----- Original Message ----- 

      From: Erin Rasmussen 

      To: 'terrapreta' 

      Sent: Saturday, April 26, 2008 12:04 PM

      Subject: [Terrapreta] FW: Simple charcoal kiln

       

      rescued from the spam filter. :) 


--------------------------------------------------------------------------

      From: folke Günther [mailto:folkeg at gmail.com] 
      Sent: Thursday, April 24, 2008 2:46 PM
      To: terrapreta
      Subject: Simple charcoal kiln

      A wonderfully simple method for making charcoal at home or on the allotment.

      http://picasaweb.google.se/folkeg/TheSimplestOfTheSimple

      -- 
      ----------------------------------------
      Folke Günther
      Kollegievägen 19
      224 73 Lund
      Sweden
      Phone: +46 (0)46 141429
      Cell: +46 (0)709 710306
      URL: http://www.holon.se/folke
      BLOG: http://folkegunther.blogspot.com/ _______________________________________________
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