biomass chunker

[Breezeblock]

ok chaps i am looking for a bit of input/advice on this type of thing https://www.youtube.com/watch?feature=player_detailpage&v=HWgAZqq6WUw

has anybody seen one in the uk or even better used one pros cons i aint sure if they are in the uk for safety issues cheers

[Marko]

We have one tractor mounted. No problems at all and makes great fuel for wood boilers. Quite a bit of info was on the thread http://arbtalk.co.uk/forum/firewood-forum/69234-i-would-like-see-what-inside.html

[Ian G 2]

Love it diy with some guards and your all good but wouldn't want my hand/arm anywhere near them blades

[forestgough]

welmac sell these machines,fully legal.The biggest model cuts 4 inch thick material.They are usually at the apf show.

Could do with someone making a boiler that is made with this type of fuel in mind,rather than straight 500mm logs neatly loaded by hand.

[difflock]

Options are a bit limited surely.

Either got to bag (an thinking a disposable net bag)

Then hand-ball into the firebox.

BUt

Bound to be voids, UNLESS someone designs a tubular firebox to suit the bag diameter.

Hmmm?

Better get my HB doodling pencil fired up.

Or use the small logs as bulk fuel.

And Load into a hopper with a loading shovel.

Buts that is a commercial op, and this stuff more likely to be a small output operation.

cheers

M

[Breezeblock]

what got me thinking was we have recently got a new 40kw eta boiler fitted and we have a chipper but wood chip isn't particularly good as a fuel for the style of our boiler as its for logs so it got me thinking about chunkers open the door and toss a bag or 2 into the fire hey presto a low value fuel turned into heat it also is easy to stack bags and i am presuming it would dry quite quirky as chunks have a good amount of surface area any thoughts or am i of a mile

[difflock]

Need(obviously) to keep the leafy stuff/very fine branches out.

Is that a "top filling" ETA boiler.

They do do one that is advertised to burn mixed timber

[Marko]

If it is going into a net then there is no need to remove leaves and small twigs as the whole lot can go into the boiler. The nets do season quickly as long as the wind can get at it. Just like logs, the nets of wood chunks don't fare very well if just put in a big heap (even inside) they really do need wind through them.

 

It is early days with the newly installed meter and a bit early in the season for some serious burns but initial trials suggest an RHI payment of around £3-£4 is generated by each well seasoned bag of wood chunks plus that leaves the conventional logs that otherwise would have been burnt available for sale. Double bubble. Now has that got your attention!

 

Top loading boilers like the Viessmann would be ideal but front loading boilers are ok to load (especially the first load). If it proves to be as worthwhile as trials indicate I am sure a hopper on wheels invention will be worth building for reloading when hot. In my mind I can picture it now but you will have to wait for a prototype or two...

 

If you do strip of the fine twigs and leaves the wood chunks are great for fueling wood ovens, chimeneas, patio fires and even BBQs if you can wait for the flames to subside. But unless you can get a big markup over and above the RHI payment why would you bother?

 

Tell me again, what Eddie is paying for a tonne of chip?

[difflock]

Ah but!

First;

How much labour is involved, or extra covered space required to get the net bags of leaves and twigs dry, I imagined"composting" taking place if they are stacked in bulk.

Second;

What price is each net bag?, not insignificent I presume (though if it allows the use of an otherwise wasted recource, no odds)

I really really do like the "concept" and my limited acreage of Birch would be just perfect for this bit of kit.

But too soon exhausted feeding a 40Kw boiler.

PS

Must get signed up for our MUCH delayed/and as not yet launched RHI scheme(with sig poorer payments than the English RHI scheme)

fume

fume!

[Marko]

Delta in labour is handling the bags ie in the example in the above photo we were just seeing how it was with hawthorne hedge cuttings (6yr growth). As horrible a job as it gets but that doesn't change whether you are throwing it through the chipper or the chunker.

 

Bags are about 30p each. For the boiler we have also trialled dropping it straight into 60ltr dustbins and putting them in a polytunnel to dry. This gets tipped straight into the boiler without bags being involved. Over the last few months that has worked a treat but the real test would be in winter; will it dry fast enough or start to go mouldy.

 

Harder work than logs.... possibly. Certainly with hedge cuttings.

But when we tried ash and hazel coppice it was a real joy and 100 bags took no time at all. Far easier than logging up with a saw.