OT - burning logs versus wood chips

Is there any difference between burning wood logs versus burning wood chips from a large chipper?

It seems like wood chips would burn up faster and not make as good of a fire as with big logs.

But is this true?

Someone, some where has probably done research on this very topic.

Thanks.

Reply to
stone
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i've always wondered about this too. why is it not possible to use a wood chipper to chip up trees/branches, put them in a wire hopper (like the way they used to do corn, a corn crib) and maybe even possibly have an auger feed mechanism into a furnace. i'm saying, so you don't have to buy pellets from corporation. it seems it would facilitate much faster drying, be easier to store, transport, etc. chipper technology is fully developed, chips would obviate the need for a expensive pelletizer machine. no splitting, stacking firewood. less dirty, no bugs, etc.

why don't people do this?!

b.w.

Reply to
William Wixon

I have no clue, but I can't help but wonder if burning chips, with forced air draft, wouldn't be much cleaner burning. Seems you could also have a smaller fire that could be easily controlled. I'm thinking how pellet stoves work---small, hot fire.

Harold

Reply to
Harold and Susan Vordos

I think that anything that is remotely combustible could be burnt if you can get the chamber hot enough. (even 99% of our garbage) They were talking about recovering something like bio diesel by poring wood chips onto white hot (liquefied) sand and bleeding off the resulting vapors (presumably starving the system of oxygen) which condensed as it cooled into a combustible engine fuel. (looked like heavy brown cutting oil)

Reply to
Allen Parks

People do this. Jut not in the US.

I use to live in Europe (read high gas prices and low availability of wood). Everything is burned. Chipping branches and other waste is almost a given in Europe. Travel to Europe and take a gander through the woods, and wonder why they are so clean of fallen branches, etc.

In Germany feeding furnaces with an auger of chipped wood is very common. Whole factories and even municipalities use such as a fuel. Although the chipped wood is not limited to branches and such, but whole trees. Reasoning being the exact reasons you stated above, ease of transportation, storage, etc. Plus it is a lot easier to send a whole tree through a chipper than splitting it.

It is odd that Europe, given its limited resources of wood, are many times more advanced at burning it than we are here in the US.

Chris

Reply to
Chris

I couldn't tell you which burns better or faster, but I wonder what happens if the power goes out. If the power goes out how do more chips get fed into the fire? Every pellet stove I have seen has had an electric feeder. Do stoves come with manual feeders? How often do they need to be fed? Can you get a stove that burns both pellets and logs? Ken

Reply to
Ken Vale

Having seen such a chipper (here in Germany / Augsburg) I must say this is impressive! 2 to 3 stems at a time with a diameter of 40..50cm are pulled in (at about 2km/h) and chipped. The chipper would't even hickup if you send some OT-poster through it. :->

Nick

Reply to
Nick Müller

That's a good thing to consider. It's the same reason I've never been interested in a waterbed.

Pete Keillor

Reply to
Pete Keillor

The electric utility in my hometown (Madison Wis) burns garbage to make electricity, or at least they did when I lived there. They run it through a hammer-mill and pull out the metals with a magnet first. Some slag drops out (mostly glass) and has to be cleaned out of the firebox periodically. In the summer it contains a lot of grass clippings, and looks like sileage (the grass "could" be composted instead, if people would separate it from the other trash).

It's a fairly straightforward modification to a standard pulverized-coal boiler (I had a tour of the plant about 20 years ago).

Reply to
Ron Bean

The wife and I have been sleeping on ours for at least a quarter century now. Our last heater burned out several years ago. Rather than feeding juice to a heater, we get along fine with one of those thick foam matress covers.

Vaughn

Reply to
Vaughn

Burning chipped wood is common at the industiral plant and power plant level. Most wood processing plants (lumber, OSB, particle board, etc) burn their scrap to produce process heat or steam. The chipped pieces are nice since you can use automated material handling.

At least one of the coal fired plants in Minnesota was retrofited to burn a mix of coal and wood chips. Starting in the late 70's, Dutch Elm disease virtually wiped out all the shade trees in the Twin Cities area. all of these had to be removed, many had nails and other debris, and elm wood is not good for lumber. Power company got relatively cheap fuel (just paid for handling and chipping), the resulting fuel was very low in sulphur, helped with their emmissions specs.

One major problem with large scale chipping of green wood is that the chips will compost rather than dying. Internal temp of a large (20' high) pile of green chips will get to 170 to 200 F within a couple of days. This makes storage pretty dicey. You can let the logs dry then chip but it takes several months to several years to get the resulting chips to dry well. Chipping to very large chips might allow air drying but there always seems to be a fair amount of fines in the resulting chips. You can always mechanically rotate and dry the result but.........

Reply to
RoyJ
[power outage]

For me, it's the reason to have no electric chair.

Nick

Reply to
Nick Müller

And the easier it wants to explode. Dust burns _very_ well, if it is blown into the burning chamber.

Nick

Reply to
Nick Müller

With a properly equipped stove, sawdust burns quite well. When I was a young lad, Victoria had a lot of sawmills, and many homes had sawdust burning stoves and furnaces. It was way cheaper than cordwood. At times a load of firewood would have a lot of sawdust in it. We used it up by burning it on top of a good wood fire.

Reply to
Steve R.

About 25 years ago I contracted to do the design work to commercialize a wood chip burner that an ME professor at the University of Maine had developed. It was supposed to be a replacement for a conventional oil burner, i.e., the intention was you would pull out your oil burner and replace it with one of these units. For a variety of regulatory and technical reasons, everyone involved should have known better.

The burner itself was perhaps about 8x10x12, had a grate about 5x5, with forced draft up thru the grate. The chips were metered by a screw conveyor and fell onto the grate, maintaining a bed 1-2 inches deep. It was indeed clean (for wood) and worked pretty well. But the burner did not have a very wide operating range; too many chips would snuff the draft; if not enough were supplied the fire would burn itself out. In other words, the burner needed to be cycled on and off, like an oil burner, which meant it required an ignitor and moderately sophisticated controls. All of which may have been doable, but the real showstopper (besides the ineptness of the company) were the regulatory hurdles involved in retrofitting the system to existing furnaces. I got fed up and bailed and as far as I know it never went any further.

There are plenty of large biomass boilers burning wood chips here in Maine in paper mills, etc., supplying steam and power for the plants, and cogenerating power for sale.

Ned Simmons

Reply to
Ned Simmons

Chip stoves don't burn chipper chips. They are pressed wax rolls that must be small enough to go through a screw or such in a hopper.

The problem with these - if you loose power - so you loose the hopper screw and ....heat. I had a friend in the lake Tahoe area - worked fine - easy to haul in a bag - clean - but they were glad they had the old wood fireplace sitting there looking pretty when power was cut. They just had to scramble and find sticks of wood outside.

Martin Martin Eastburn @ home at Lions' Lair with our computer lionslair at consolidated dot net NRA LOH, NRA Life NRA Second Amendment Task Force Charter Founder

st> Is there any difference between burning

Reply to
Martin H. Eastburn

Put in a dryer and a silo - a pto ramp to load the silo and naturally a silo house to get it out the bottom... :-) Martin Martin Eastburn @ home at Lions' Lair with our computer lionslair at consolidated dot net NRA LOH, NRA Life NRA Second Amendment Task Force Charter Founder

William Wix> i've always wondered about this too.

Reply to
Martin H. Eastburn

It also makes a great firestarter if you stir enough old motor oil in the sawdust to just start making it clumpy. My dad keeps a small bucket of it near the woodstove for starting the fire- all you need is a cup or so, single match to light it and no newspaper or kindling req'd.

Gregm

Reply to
Greg Menke

I must take a real strong exception to your statement about the low availability of wood in Europe. In the early 90's my wife and I went to Germany to visit and go camping with our son who was stationed there in the US Army. At one point, near Titisee in the Black Forest of Bavaria, we went for a long hike into a large forested area. We found hundreds of cords of wood stacked and rotting in the forest. It was left from thining operations.

On another occation we were with son's girl friend and her mother near Rottenberg. We saw a very large sawmill that had not been in operation for some time. There were huge log decks there with fairly large trees growing out of the rotting logs.

So, while there are lots of places in Europe with few trees and other natural energy sources, it sure isn't true generally!

Paul

Chris wrote:

Reply to
pdrahn

Paul, The stacked wood that you mentioned; was is split in one meter lengths? If so that is firewood that is normally stored in the woods. If it was along side the trail, than that is exactly what it is.

If it was large thinning operation, what you most likely saw was a government program on government land (although they will go onto private land if it is not maintained). Cannot speak for what they did with the wood, although I can say that it is not always put to good use. I can only assume that it was not left to rot as one of the largest problems in Germany are wood beetles that can really do harm. You can confirm this if they were compete logs, as they most likely were debarked.

Although the thinning operation should give you a clue. They do this to help preserve the forests, something that is scarce in most of Western Europe. If you were fortunate enough, you might of been able to see some of the machines that they use, really impressive.

I think you mean "Rothenburg ob der Tauber", as it is one of the largest tourist traps in Germany. I use to live and farm within spitting distance from there. Walk through the woods in that area, it will not take you long. Or better yet watch how they hunt in that area. :) Not very often I used to sell some of the excess firewood. If I remember correctly it went for something like $240 a sq meter for pine in the late

80s or early 90s. I would guess that 90% of the wood burned was pine in that area. Do not even want to mention how much I sold two oaks for. Let us just say that you hold an auction for the larger ones, were they come out an look at individual trees.

A better tour would of been trying to find a place that sells wood. To be honest I cannot think of one store that sold a significant amount of wood in Germany, although I lived in the farming area. Fortunate enough, that when I needed new timbers for the roof we cut our own.

I am sure there is a number somewhere, but I would completely guess that the

20 times more forest per human in the US as compared to Western Europe.. Not sure either, but I think that Western Europe imports most of the wood they use in construction.

Ya have to remember that Germany has 80mil people in a land the size of Colorado, and has been inhabited well before anyone knew the world was round.

Chris

Reply to
Chris

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