[Terrapreta] Part II comments on John Cowan's "thoughts"

[Sean K. Barry]

Hi Ron,

The ideal gas law is PV = nRT, pressure times volume equals the number of moles times Boltzmann's constant times the temperature in Kelvin

Volume, number of moles, and Boltzman's constant are all constant in a sealed autoclave, So, P = nRT/V, or P = some constant * T.
Therefore the ratio of increase in pressure is linear with the ratio of increase in temperature.  Assuming room temperature when the autoclave is loaded and sealed to be 25 degrees C and the atmospheric pressure to be 14.7 psi, then

P(180) = [(180 + 273.15) * P(25)]/(25 + 273.15) = 1.52*P(25)

The pressure inside the autoclave at 180C will be approximately 1.52*14.7psi = 22.3 psi

QED

SKB
            
  ----- Original Message ----- 
  From: Juergen Botz<mailto:jurgen at botz.org> 
  To: Ron Larson<mailto:rongretlarson at comcast.net> ; terrapreta at bioenergylists.org<mailto:terrapreta at bioenergylists.org> 
  Sent: Friday, April 20, 2007 10:22 AM
  Subject: Re: [Terrapreta] Part II comments on John Cowan's "thoughts"


  Ron Larson wrote:
  > [re: pressure cooking biomass to produce "coal"]
  > a. Like John, I found this new and very interesting. [...]

  Same here... it would be a zero loss conversion that not only produces
  coal but also better retains other elements that could be useful to 
  the soil.

  >     c.  After 15 hours at 180 C, one ends up only with water
  > and tiny "coal" spheres - with the system being exothermal!
  > (in the presence of a [secret?] undisclosed catalyst)

  Citric acid.  Says so in the DW article.

  >     d.  They talked about doing the research outside because
  > of the dangers of an explosion. This reminds me of the similar

  A normal pressure cooker or sterilization autoclave produces 
  temperatures of only 127 deg Celcius as far as I know.  What
  kind of pressure do you need to heat steam to 180 deg C?  Anyone
  know?  Are there off-the shelf autoclaves that can handle that
  kind of pressure?

  >     e. They talk about using the "coal" in a fuel cell - no
  > discussion of use as a soil augmentation, so maybe this
  > product is not as permanent as we might desire.  It also may
  > have little surface area.

  Again, the DW article does mention soil... quote:

        We can adjust our coal to be just a bit refined, or we can
     cook it until it's like hard coal. One end of the spectrum is
     topsoil, the other is hard coal."

        When the researchers cook their coal mixture for just five
     hours, the result is topsoil,

        This nutrient-rich earth can be used to help barren
     landscapes bloom.

  So, cook for 5 hours for soil, for 12 hours for hard coal.

  Still it leaves a lot of questions unanswered.  Although the 
  Max-Planck press release speaks of "tiny spherical coal particles"
  and even "Carbon nano-balls", there is no real information on the
  structure of this coal or the size of the particles.  

  I'd love to learn more, and even try this.

  :j


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