an alternative kiln firing fuel, and a firewood dry kiln.

[timfromtang]

Greetings folks,
I am new here (please don't bite)
There's a bit of a back story to this one.
We are a small (100 acre) young forest (once a mixed farm) in Ireland, planted 1996, 2001, 2003, 2011.
We are just starting first thinning on the 2001/2003 planting (about 40 acres mixed hardwood and some larch)
This planting has issues... plant spacing too close and density too high.. with the consequence that there will be a low yield of firewood sized timber, and a large proportion of sticks in the 90-50mm dia range (3 1/2" to 2" dia)

A firewood kiln would add value to the small volume of firewood....
It would be nice to convert some of the "too small for firewood" sticks into a saleable product.

I have a plan........
there are unresolved issues and i'd love some input from expert folks here

What if we could fire our timber dry kilns and conserve the monetary value of the fuel used to fire the kiln somehow???

I propose using waste heat from charcoal production as a source of process heat for the firewood dry kiln. With the benefit of turning too small to be saleable as firewood material into charcoal and ultimately into euros.

initially i am building a "1 cord" prototype, to dry 1 and 2/5ths of a cord per run, the 2/5 is the fuel for the charcoal retort for the next firing.

would i be very wrong in assuming 1/5 (dry) cord to kiln dry one cord with a standard boiler fired kiln
further assuming that half of this heat should be available as waste heat from a charcoal making process

I have designed a closed retort system of charcoal production which burns the "waste gases" and stores the thermal energy released in a thermal mass which is used to heat the kiln.

I am planning a high temperature design circa 100 deg C

I'd really appreciate the opportunity to correspond with others concerning various technical problems etc i will encounter as i build my prototype.

I am open to constructive ideas concerning kiln design.

This should be a scale-able technology, and hopefully the recovery of the charcoal will have economic benefits.
There is also potential to bury the charcoal with environmental benefits, although the high reaction temperature of my retort design should produce a charcoal more suited to the metallurgical craft market (i am aiming at producing metallurgical charcoal as i have links with smiths).

the scale of the prototype is designed to suit our operation drying 2 cords a week will be sufficient, it is far from fulltime firewood processors.

timfromtang