[Terrapreta] Strong warning against "simple" charcoal kilns

[Sean K. Barry]

Hi Kurt,

You're right , I'm wrong.  Thanks for correcting me.  The term "reduction" in chemistry means "removal of oxygen" and is as you describe endothermic.  "Combustion" is the correct term for the combination of Carbon monoxide-CO with Oxygen-O2 to make Carbon dioxide-CO2 and the combination of Hydrogen gas-H2 with Oxygen-O2 to make H2O.  Both liberate energy (are exothermic).

2CO + O2 => CO2 + heat

2H2 + O2 => H2O + heat

I'm humbled to admit that in my sleepy state last night I tripped up on the terminology.

Nonetheless, CO and H2 burn before the CH4 and CO and H2 are 10 times more prevalent in "producer gas" than is CH4.

Regards,

SKB
  ----- Original Message ----- 
  From: Kurt Treutlein<mailto:rukurt at westnet.com.au> 
  To: terrapreta<mailto:terrapreta at bioenergylists.org> 
  Sent: Monday, April 28, 2008 6:34 AM
  Subject: Re: [Terrapreta] Strong warning against "simple" charcoal kilns


  Sean K. Barry wrote:
  >  Hi Kurt,
  >
  >  I  "Open-air" reduction of H2 and CO in the "producer gas" will use
  >  as much as 5 times the amount of oxygen as the CH4 will BEFORE the
  >  CH4 will reduce.

  It seems you still need to be taught basic chemistry. It is not 
  "reduction" of H2 and CO and CH4 that uses O2. The process is called 
  oxidation. In other words combustion. Which is exothermic by the way.

  Reduction uses hot carbon and would involve a re-action between Carbon 
  and H20 and CO2, resulting in the formation of H2 and CO.
  And this process is endothermic, ie it absorbs heat.

  But then you're probably getting tired and befuddled with all the 
  formulae that you're typing up.

  Have a good sleep now and perhaps tomorrow you'll wake up all refreshed 
  and clear of thought.

  regards,

  Kurt

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