[Terrapreta] CEC

[Tom Miles]

Wayne,

For the last few years we have looked at the feasibility of a fixed or
modular pyrolyzer to handle these residues. There are some significant
economic challenges for just making charcoal. So we've looked at bio-oil to
offset the costs of processing and using the char byproduct. The economic
challenges are still significant. The logistics are also complicated by the
fact that we have many different organizations that are the stewards of the
forest. Each has its own record of performance when it comes to actually
preparing an area for sale or treatment. We still think this is possible but
at the high costs of removal and transportation energy alone can't pay for
the treatment. There needs to be a policy decision to spend public funds to
do the treatment and let private enterprise convert the carbon to value
added products.

As a matter of interest the cost of delivered forest residues to a fixed
plant just outside the forest is about the same as urban residues in our
area: $50/dry ton. That's equivalent to $125-$200/ton charcoal at yields of
40%-25% respectively before processing. If instead you convert 70% to oil at
$1/gal and 15% to char at $100/ton your products are worth about $100/ton
dry wood at the plant. You have $50/ton to own and operate the plant
including packaging and selling the products. A 50 tpd plant processing
approximately 2 tons per hour will have $100/hour to run the plant and the
business.  

Still working on it. . .           


Tom



> One final comment.  Though I don't like the idea of charring trees,
> forests commonly produce a lot of woody material that outside the wet
> tropics will remain as forest floor debris for a long time.  Anti-fire
> advocates would love to see that cleaned up to prevent the huge fires
> we have seen in the west in the past two decades.  Why not char that?
> You could reduce fire risk and improve soil at the same time.  To
> increase the soil organic matter you could compost the leaves and
> twigs, just charring the slightly bigger material.
> 
> Wayne