| Archive for countrytalkandtips.myfreeforum.org ........................ smallholding, crafts and country life ................................................... IN IRELAND ....................................................... |
| Graney |
Willow and/or pellets?Apologies for opening up a new thread on this topic, but the last one faded out into a discussion about wood gas and some issues about willow were left unresolved.We are planning a new heating system to replace an ageing Stanley. Ideally we would like to be able to make use of the large quantity of willow we have available - not enough to supply all our fuel needs, but there ought to be sufficient to make a substantial contribution. The obvious choice seems a combination of pellets and willow. The questions that spring to mind are: What combined fuel boilers are appropriate and recommended? Do combined fuel boilers quality for a grant? How is willow prepared for use? Is it best to cut, dry then chip or cut, chip then dry? And how long and under what conditions should the drying be done? What chippers are suitable? Large chippers seem to be pretty expensive. Any help or guidance would be much appreciated. |
| Graney |
No thoughts at all ? 
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| blowin |
Hi Graney , I don't know anything about the technology but just thought I'd keep you company  .
What kind of willow do you have ? More to the point , what is its growth habit ? The stuff which grows all over the place around here is mostly Goat Willow . It burns ok but the branches are very twisted . This makes them difficult to handle & store in bulk . They would take forever to put thru even a big commercial chipper . Hopefully yours grows reasonably straight . 
I think any wood will chip better when green than seasoned ( ie won't blunt the teeth so quickly ) but I imagine you would get a build up of heat in a big pile of fresh willow chips . Hope that helps tho I suspect it doesn't !
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| Graney |
Thanks Blowin.
Most of the willow I have available is Salix viminalis, the Common Osier, so I can get straight shoots of 10 feet or more in a year. The point you raise about chipping green is exactly the one I was struggling with. Chipping green would be great if I was trying to compost it - but that kind of defeats the object of the exercise. I can see the added difficulty of chipping dry - hence the question about the cheapest chipper I can get away with to do the job - but I can't see any other way round the composting problem. I can't believe there isn't experience out there to help on such a basic question, but I've searched appropriate sites and can't find any reference. I just thought that as there had been 60-odd viewings of the thread, it was surprising nobody had felt able to contribute any thoughts. |
| admin |
There might be some clues in this extract from : http://www.farmersjournal.ie/2006...armmanagement/crops/feature.shtml
A Forage Harvester, with a modified maize header specifically adapted for use with willow can be used successfully for harvesting. The willows are chipped whilst going through the harvester, blown into a silage trailer and taken back to the yard where they are tipped onto a grain drying floor for drying. At time of harvesting, willows have a typical moisture content of 50%. Normally a harvester can cut up to six hectares per day dependant upon ground conditions and accessibility. |
| Graney |
Sounds like .... first build your grain dryer. A little bit beyond me, I think.
It also begs the question, how much energy is used to get the moisture content down to an acceptable level? Surely there must be a way of using biomass suitable for the likes of me with the raw materials readily available .... and a flexible amount of non-chargeable labour available. |
| blowin |
I found a few other sites but none of them was particularly informative . They generally seemed in favour of seasoning for at least 6 months before chipping . They also mention that the pellets are made of chips and sawdust so I guess that means mixing and compressing everything too ?
I hope someone can help more than I have been able to ! |
| wayland |
This is a subject close to my heart, ever since I heard that Woburn abbey was heated by Willow chips. The concept was that the forage harvester would chip stands of two years old, and dry them over a one year period. Not wanting to stretch ones maths to work out the number of lays to give a year long continuous supply of chips. So the problem is in the storage. The idea of course is that the chips dry and not compost. This involved much mechanical handling but not a problem if space is freely available. Good luck guys.
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| Graney |
The Eden project also made a big thing in front of their recently pruned willow that all the prunings went into the heating system for the biomes.
Not much bloody good if you have to have lots of machinery and driers to give you the fuel to burn. I can't believe there's not a way to make biomass work on a 'small' scale |
| wayland |
It would have been done on a small scale in the experimental stage. I would be surprised if someone has not written a paper on it. I would think that Scandinavia, Holland are the experts on the subject. The Duke of Bedford is a good bloke. Perhaps an email to Woburn Abby would get a response. As I mentioned earlier the drying of the chips will generate alot of heat as the chips try to ferment. This heat would dry the chips and providing you turned the heap regularly to let the heat/moisture out this would work I think  . If you were to put a steel bar into the centre of the heap and pull it out from time to time and feel the heat in the bar this would give you an indication when to turn it. Anyone who has made a compost heap and not had enough moisture in it would understand the theory I think. Rambling a bit  Good Luck.
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