[Terrapreta] Fw: Terra Preta Trials 2007

[Sean K. Barry]

----- Original Message ----- 
From: Sean K. Barry<mailto:sean.barry at juno.com> 
To: Ron Larson<mailto:rongretlarson at comcast.net> 
Sent: Sunday, March 25, 2007 10:44 PM
Subject: Re: [Terrapreta] Terra Preta Trials 2007


Hi Ron and All,

Coal cannot replace charcoal as a carbon-sequestering soil amendment, because coal will not take CO2 carbon from the atmosphere.  Coal also has heavy metals, like mercury, uranium, thorium, radon, etc.  No one would want that spread onto the soil any more of that, than is already being spread by coal burning power-plants.

IGCC stands for Integrated Gasification Combined Cycle.  In an IGCC power plant coal is first gasified, then burned through a gas-turbine, which turns and electric generator.  This energy conversion cycle (heat to electricity) is then COMBINED again with another cycle; the exhaust heat from the gas-turbine is used to heat water to steam and that is run through a steam-turbine, which then also turns an electric generator.  The advantage of using IGCC in power-plants is that more energy can be harvested in the form of electricity than by the conventional method of burning pulverized coal to heat water and power steam-turbine generators.

The energy conversion efficiency is higher, so you get more electricity from the same amount of coal, or use less coal for the same amount of electricity.  Nothing about IGCC reduces the amount of CO2 released from using the coal.  In fact, more CO2 may be released per ton of coal used for IGCC than per ton of coal combusted.  But, less coal will be used.  Also, IGCC is cleaner because the other potentially more harmful pollutants; mercury, uranium, thorium, radon, Sulfer oxides (SOx) , nitrogen oxides (NOx) are NOT released when the coal is gasified instead of combusted.

Another neat thing about IGCC, is that it is an easier retro-fit to conventional coal burning power-plants than pollution scrubbers.
The plant could be made more efficient and cleaner with less expensive IGCC retro-fits.  Xcel Energy hates the IGCC plant running at the Mesaba Energy Project in Minnesota because by law they have to buy the power back from that utility, and that utility is producing electricity at much lower cost than they currently can.  Builiding IGCC retro-fits might be a very good business to be into.

If you took the final exhaust heat and clean CO2 from an IGCC power-plant, bubbled it through clear glass pipes out on the desert (clear, so sunlight gets in), that were filled with algae and water, harvested the algae bloom, dried it, turned it into charcoal, and put that into soil (in the desert), then you could call that carbon from that coal sequestered.

Regards,

Sean K. Barry
Principal Engineer/Owner
Troposphere Energy, LLC
11170 142nd St. N.
Stillwater, MN 55082
(651) 351-0711 (Home/Fax)
(651) 285-0904 (Cell)
sean.barry at juno.com<mailto:sean.barry at juno.com>
  ----- Original Message ----- 
  From: Ron Larson<mailto:rongretlarson at comcast.net> 
  To: Robert Niederman<mailto:rniederman at cegworldwide.com> ; rukurt at westnet.com.au<mailto:rukurt at westnet.com.au> ; terrapreta at bioenergylists.org<mailto:terrapreta at bioenergylists.org> 
  Sent: Sunday, March 25, 2007 10:10 PM
  Subject: Re: [Terrapreta] Terra Preta Trials 2007


  Answer to question from Robert Niederman, asking today:

  > I have a question.  I've run across this concept that making charcoal
  > actually ""sequesters" carbon.  Sequester a beautiful word.  But what
  > does it actually mean when it comes to making charcoal?  Every fire I
  > have seen, including those made with charcoal have lots of smoke.  Yes,
  > we have carbon in the charcoal.  But we also have about half of it in
  > the atmosphere. Where does the "sequestering" come in?  Are we saying
  > that by making charcoal we are pulling the carbon out of the
  > decomposition chain which occurs when we compost?

       I would say you have the idea behind the word "sequester" approximately 
  correct. But making the charcoal is not enough, since the charcoal itself 
  can be later burned.  The sequestering comes when the charcoal is 
  sufficiently well mixed in the soil that it cannot be "un-mixed."

      Re your last sentence, I would add that we have to also remind people 
  that the photosynthesis process is taking CO2 out of the atmosphere (using 
  sunlight) to create the biomass that can be pyrolyzed ("charcoaled").  You 
  are of course correct about compost decomposition being prevented, and we 
  need to educate that charcoal is "almost" unable to be decomposed.

      Most discussion on the web about "sequestration" assumes that CO2 from 
  burning fossil (almost always talking coal) resources is liquified and 
  "stored/sequestered" at great depths.  Despite billions of federal dollars 
  in so called "clean coal" research, there are no real-world working examples 
  of CCS = carbon capture and sequestration.  I exclude EOR enhanced oil 
  recovery as a realistic CCS alternative, since that approach leaves lots of 
  chance for release through the thousands of drill-holes in most oil and gas 
  fields.  When you see the word IGCC, there is an implied CCS option about 
  which there is rarely any discussion.   Terra Preta soils as an alternative 
  means of sequestration avoids huge costs and uncertainties that the utility 
  and coal industries have chosen to procrastinate on when they are not 
  ignoring the topic.  IGCC itself has very serious cost problems - but the 
  main problem is with the CCS portion of the duo.

      You also give me a chance to raise the question from several weeks ago 
  about placing coal dust rather than charcoal into the soil.  I have looked 
  and found nothing meaningful - but think this is apt to be a real loser. 
  Coal is the major source of uranium.  Coal has none of the porosity 
  characteristics of charcoal.  Has anyone found anything to suggest coal 
  could replace charcoal?

  Ron 


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