[Stoves] Chip drying without pyrolysing; Biocoal manufacture.

[ajheggie at gmail.com]

[Default] On Sat, 25 Jan 2014 20:23:14 -0500,Alex English
<english at kingston.net> wrote:

>If I were to dry wood chips, I'd be building a variation on the linear 
>corn crib.
>
>http://tinyurl.com/pdq4uhp
>
>Wide enough for a loader  and  a minimum of 7 meters tall*.*  Planks at 
>loader scraping height with wire or chain link fencing above. 
>Polyethylene roof. Orient it across the path of the summer winds if 
>possible.
>
>Having tried it at a smaller scale, I'm inclined to think it would work 
>here with one or two good drying months  out of twelve.

I've always advocated using solar energy for drying and this is just
another example.

I've discussed much the same with a local farmer and woodchip boiler
owner, he has a three sided barn which he uses a bucket loader to move
the chips around and present fresh surface to the air. We have
considered using pallets on their side in a configuration like your
corn crib.

In UK we have about 1m of rain (more this year than most) and about
30cm of evaporation so a large chip heap soaks up more moisture than
it loses if it cannot shed or drain rain.

As a vegetation management company we produce chip all the year round
and it's impractical for us to store it for a season, so it's shipped
to a biomass plant on a regular basis at 45% mc wwb.

On the smaller boilers it really needs to get below 30%mc in order to
have a clean burn. A clean burn requires high temperature combustion
and on a lossy burner it is simply not possible to raise all the water
to the required temperature.

This is exacerbated in char making as you are trying to retain 50% of
the energy in the byproduct, which is why pre drying is more important
in char making.

AJH