[Terrapreta] Carbon Neutral Composts

[Brian Hans]

Steve,
   
  I would agree with what Greg and April just said and add...
   
  Technically, compost would always be carbon negative to the ATM because of the minute amount of stable carbon being formed that remains in the soil for a very long time. And because 100% of all the C from biomass is from ATM CO2, composting is always carbon negative. The concern you are expressing is about the GreenHouseGas emission or GHG of the compost pile. Carbon can emit in many forms, some of them better than others. 100% CH4 production of biomass would be carbon neutral to the ATM but 40x more GHG pollution than if one just burned the biomass completely into CO2. 
   
  Generalizing, the less moisture the biomass and compost system has, the less Anaerobic digestion happens and thus, less CH4 production. 
   
  Again, generalizing, the less S, N and other potential emission concerns in the starting feedstock, the less SOx, NOx, and others emissions of the compost... 
   
  These generalities ought to show us that wet digestion of manure is a very bad no-no. Wet digestion of anything like rice patties, organic matter eroded off of farmer joe's place into the local swamp, cattail marshes, digestion of cocoa bean hulls in the tropics... If GHG and other ATM emissions is of concern, as it should be, then wet digestion should specifically be a major target for exactly the reason you are asking about.
   
  Which is why gasification/TP/re-mineralization techniques are so important and likely the reason why many of us are here, reading and writing. 
  
Generalizing yet again, charcoal in the soil is always ATM carbon negative but not GHG negative. 
   
  As to specific rates... the LCA of products are few and far between. The last thing someone wants to do is record and tell the world their pollution. This is some of the issues that cap/trade or carbon tax or whatever GHG tax comes to pass will have to deal with. Im sure one could dig up everything they would need to do that research. 
   
  Brian

     
  ----- Original Message ----- 
    From: Stephen Hayden 
  To: Terrapreta at bioenergylists.org 
  Sent: Wednesday, May 21, 2008 21:26
  Subject: [Terrapreta] Carbon Neutral Composts
  

  To all,
  I have an idea to incorporate char into composts and soiless mediums to offset their carbon, methane and nitrous oxide emissions on decomposition and make their use carbon-neutral.  Can anyone tell me at what rates and amounts of these gases can be anticipated for typical organic materials such as manures, peat, bark, coir, etc.?  Thanks!
  Steve Hayden
  Solid Ground 
    
---------------------------------
    
_______________________________________________
Terrapreta mailing list
Terrapreta at bioenergylists.org
http://tech.groups.yahoo.com/group/biochar/
http://terrapreta.bioenergylists.org
http://info.bioenergylists.org_______________________________________________
Terrapreta mailing list
Terrapreta at bioenergylists.org
http://tech.groups.yahoo.com/group/biochar/
http://terrapreta.bioenergylists.org
http://info.bioenergylists.org
-------------- next part --------------
An HTML attachment was scrubbed...
URL: /attachments/20080522/4e09a2d2/attachment.html