Burinig wood chips

[nymapleguy607]

Hey everyone, Just thinking out loud but I wanted to get your thoughts on using wood chips as a fuel source. This past summer the power line trimmers came through and trimmed the lines so there are a lot of branches that are to small to be worth while as cord wood but I was debating if I chipped them and stored them in something like a corn crib then burned them by the shovel full. My arch is a gasification type so I believe that I would be able to burn them all right. I want to put a pyrometer under the flue pan and use that to controll the air and firing times. I figure I could start the fire on regular wood and then add chips onto the coal bed and let them burn down. I dont mind opening the door to fire, burning the chips would just help keep my woods cleaner and eliminate brush piles. Any thoughts or comments are appreciated.
Jeff

[Scribner's Mountain Maple]

I think it would work good if you could get them to dry and be able to rotate the Pile. I'm not familiar with a corn crib, so maybe that's what that does. I am thinking something like a compost bin that allows you to turn the pile for better drying.

I think the idea is great. I would chip my tops and try to use them in the arch if I had a chipper. I burn a lot of my brush piles in the interest of cleaning things up, and everytime I light one up and watch it burn, the thought comes to my mind how much syrup could I have made with all those BTU's wasted. So more power to you and let us know how it works if you try it.

Again, I think the key to success will be in getting the chips dry.

Good luck.

[maple flats]

That is what VVS FFA do in their operation. They reportedly have the only evaporator in the US designed to burn chips. They grow willow brush, then chip and dry it. They also get chips from other sources. The chips are then fed into the evaporator by a conveyor into a hopper and by auger into the arch. It was being demonstrated last Jan. at the NY winter maple conference in Verona, NY. I believe the arch was made by CDL. The mfgr's rep said the ideal moisture content was 15-30% moisture.
To burn chips without something designed to feed the fire and get the right amount of air into the chips may prove problematic. If that and the issue of flash back fire can be solved they will burn well.

[lew]

Dave,

There are other wood chip fired arches in the U.S. Gagnes in VT have one that I know of and actually Waterloo Small delved into this technology in the '80's I believe. They installed 2 arches at a sugarhouse down near Hobart I believe. They are around. I am just looking into building one now.

[tuckermtn]

"Mark" on here has a wood chip fueled arch. Very nice looking set-up. uses a corn-crib like storage unit and a conveyor. Hopefully he will chime in here.

[maple flats]

Sorry, I stand corrected. It might be maybe the only one by CDL then. Anyway, I heard that in Jan. and again on the local news by Time Warner just a few days ago.
I had also thought of chips and pellets being a great option. Then I priced an arch and thought again. If it becomes more feasible I'll likely go that route someday.
I do have a sawmill and a chipper so some of the chips and my slab wood issue could be solved with one. I also have many other sources for chips and pellets in bulk delivery are a decent option too. Still cheaper than oil and the arch is far quieter than oil. Besides, local fuel is better than imported or even domestic oil.

[MapleMark753]

A purchased, or home made device may work for smaller hobbyists or producers. I've seen wood chip and sawdust brick formers where basically you load wet chips in a form that makes brick sized pieces, press them to form them and push water out, stack and dry them out, and use them as would be used regular split firewood. Anyone try this?
We may try this (small scale) as the brush piles in the woods seem to multiply quickly when thinning and cutting firewood.
take care, Mark

[nymapleguy607]

My thought is to store them loose and basically burn them by the shovel full once I have a bed of coals. I am thinking that the under fire air will help burn the pile and the over fire air will burn the smoke. I still think I would need to fire every 5-7min but the labor involved making chips seems a bit less than cutting cord wood.

[Thompson's Tree Farm]

If I remember correctly, Paul Smith's College was chipping their slabs and burning the chips in their evaporator in the late '80's. Think they said the biggest issue was getting them dry enough.

[maple flats]

For sure an issue would be spontaneous combustion. If too much moisture is in the chips and they start to decompose they generate heat. In a poorly vented storage this heat would build until it could spontaneously ignite. Same as in barn fires if the hay is not properly dried. To dry a large amount of chips be sure to incorporate some vent pipes in the storage bin or structure. A simple pipe with vent holes in it, standing vertically, with it venting above the chips but shielded from moisture getting in is all you would need, Maybe 1 every few feet in a larger storage area. I don't know how many would be needed but I'd guess every 6' in all directions would suffice. I'd rather have more than needed than 1 too few.

[nymapleguy607]

I do worry about the possibility for spontaneous combustion but my thought would be to let the brush season a little and then chip the pile. I would like to make a crib to keep the chips in and have slats on the outside with about a 2" gap to allow air to come through, I thought about running a pipe horizonally through the center with 1/2" holes and putting something like an exhaust fan to draw air though the chips. Similar to how ear corn used to be stored.

[twobears1224]

I plan on building my own chip burner and I,ve done a ton of research on it.one thing I,ve found is the fact that you don,t want the chips to dry.if there to dry they won,t burn right and they will be abrasive on your equipment if you use conveyors,ect.you also need to be very careful because you can get blowup by wood gas.. look up chiptex on the web it,s a company in Vermont that makes wood fired boilers at one time small brothers sold there burners as a add-on to there archs.

[twobears1224]

if you look around theres a bunch of producers using woodchip and some of them have been doing it for many years..likes been said mark on here does it and I know theres some in Vermont that have done it for years.

[halfast tapper]

There is a sugarhouse in brattleboro area that has been burning wood chips for years. You definately don't want to dry the chips. If you dry them when they enter the arch they will not gassify. Just like the new gassifacation arches you shouldn't burn really dry wood doesnt work as well as green wood. There is a Monistery near me that heats all their buildings by a wood chip boiler set up. They used to burn 4 foot wood, 120 cords of wood a year. Then they converted to wood chips. Built a big storage building that they chip up the wood and blow the chips directly into the building. They then transport the chips using their farm tractors and silage wagons.

[collinsmapleman2012]

The Chip Evaporator worked pretty decent at VVS, I graduated from there in 2012, and i went back last year and helped with the maple production. The chips worked prety well as long as they were reasonably dry to the touch. The FFA there has a 3 acre willow plot that is used to demonstrate biomass and bioenergy systems to students and the community. Because of the way that the chips were stored in the first year(pile with a tarp on it), the chips had some ice in them and we wound up mixing the willow chips with soft maple chips and it provided a hot fire and good efficiency. The arch is a CDL 4X12, and the chips are put in a hopper at the rear of the evaporator, where they are augered in and combust at the bottom of the rear of the machine. The heat then flows to the front so it is the most intense near the syrup pan and then flows towards the rear through the flue pan and out the stack. The chip-fired arch was a fairly new venture to CDL, and we thought there could be a few improvements to the machine because of chip delivery(the chips would bridge over the auger), a couple times the fire backdrafted a little and we had smoke in the chip box, and a couple minor things. We were seeing temperatures of 1200-1600 degrees at the syrup pan, 750-950 degrees at the flue pan, and 400-600 degrees at a few feet up the stack. The evaporator did around 120-150 gph, running concentrate that was usually about 8-12 percent. I really thought that the evaporator worked well overall because of the efficiency of the burn, as well as the low cost of the fuel. if there were producers that were looking to use up wood and/or chips that they had, i feel like a chip evaporator would be a good option because of how efficiently the chips burned. The January Maple Conference held at VVS has a tour of the saphouse, as well as a demo of the evaporator. also, it is on display during maple weekend and any time during maple season. If you are in the area, I highly recommend taking a look at the evaporator because of the efficiency and viability of the project.

[BreezyHill]

We use chips under our show cows for bedding. If the branches are not already dry you will have a difficult time getting them dry. The chips landscapers and the town have dropped off are green and start to compost within days. In one year they are pretty soft. Year and a half and you can spread them in the garden. We bed down with them in all states. The pack is then cleaned out and added to the compost pile and spread a year later.
If they are dry they will work fine I have burned dry chips in an air under system with marginal results. To much surface area and not enough air makes for some pretty nasty smoke. I am building an AOF system that should eliminate that issue; but I will be sticking with not less than pallet material as a rule. Not to say I would not throw in floor sweeping to clean the wood area up.

[Mark]

I don't know why everyone says you need wet chips to gassify. Dry wood still has 20% moisture and anything more slows you down. I have run mine for 13 years and dry wood is much faster.

Fresh cut chips gives me about 225 gallons an hour and dry chips brings it over 300. If you want to slow it down just use chips with sawdust, kind of like throwing a wet blanket on it.

[Mark]

We use chips under our show cows for bedding. If the branches are not already dry you will have a difficult time getting them dry. The chips landscapers and the town have dropped off are green and start to compost within days. In one year they are pretty soft. Year and a half and you can spread them in the garden. We bed down with them in all states. The pack is then cleaned out and added to the compost pile and spread a year later.
If they are dry they will work fine I have burned dry chips in an air under system with marginal results. To much surface area and not enough air makes for some pretty nasty smoke. I am building an AOF system that should eliminate that issue; but I will be sticking with not less than pallet material as a rule. Not to say I would not throw in floor sweeping to clean the wood area up. A gasifier usually burns the chips in an oxygen starved environment to produce smoke and the smoke is burned in a different area. The smoke is then mixed with more air and burned under the pans. At least that is how mine works. Look at the producer gas systems that power a vehicle on wood smoke.

[twobears1224]

sorry about mistyping the name it,s chiptec that builds chip burners in Vermont. I have a old small brothers catalog and they have them in there..it,s a add-on type unit that sits infront of the arch.to clear things up alittle.i,ve worked with wood in pretty much all of it,s forms for years and to me 20% moisture content is wet wood to me dry wood would be in the 8/10% range..so when I say wet wood I,am talking in the 20% range.most everything I,ve read on burning woodchips says they need to be in that range. dry chips burn to fast don,t give off a lot of good gas and can wear your equipment out to fast.i also agree with mark on going with a producer gas type burner.i have a good link on that and it,ll look it up and post it here..

[Mark]

sorry about mistyping the name it,s chiptec that builds chip burners in Vermont. I have a old small brothers catalog and they have them in there..it,s a add-on type unit that sits infront of the arch.to clear things up alittle.i,ve worked with wood in pretty much all of it,s forms for years and to me 20% moisture content is wet wood to me dry wood would be in the 8/10% range..so when I say wet wood I,am talking in the 20% range.most everything I,ve read on burning woodchips says they need to be in that range. dry chips burn to fast don,t give off a lot of good gas and can wear your equipment out to fast.i also agree with mark on going with a producer gas type burner.i have a good link on that and it,ll look it up and post it here..
That 20% number I gave is too high after thinking about it, never really measured them. The chips that burn the best are the ones that are as dry as they can get. We don't always empty the chip bin every year so the chips that have been in there over a year are real dry. The ones that are next to the screen walls and in the sun. When we get into those the temps are the highest and the evaporator really goes. The last couple years I have been running with thermocouples under the pans and it gives me a very good feel for what is going on. The dry chips will up the temps under the pans about 500 degrees more. The extra moisture from the chips that feel dry to the touch but fresh interfere with the mixing of the combustible gasses and the oxygen. My gasifier is not under the pans but in front. I can control my primary and secondary air and can control how fast the chips burn but usually go as fast as I can with the current speed I have set on the induced draft fan. A change for next year is variable speed motor on the fan. To change it now I have to adjust the pulleys and have left it at a slower speed to save chips. Once I get my own chipper I won't worry about chip consumption. I had it at a higher speed for testing and it would go through 700 pounds an hour of chips but was worried about efficiency.

The big advantage pellets have is they are bone dry but I won't spend the money on them.

[maple flats]

What sort of storage facility do you have.
When the manufacturer rep. for the chip fed evaporator at VVS FFA, in Verona told me they want 15-30% moisture it puzzled me, but I believed they knew what they were talking about. Maybe they meant to say they could burn up to 30%. I saw now way for it to burn efficiently, but again, I took them at their word. What you are saying about burning dry chips is totally in line with what I thought before talking to that rep.
I am very interested in burning chips.
Do you burn any chips or do you require then to be hardwood, or specific size, or trunk/limb only no leaves. I have a sawmill and a chipper. I could chip all the slab if bark% is not a factor. I also have lots of wood that could be utilized for chipping. Do you run a conveyor into an auger fed burner?

[Mark]

There are some pictures on my site. I keep the chips in a building like a corn crib. They are sawmill chips when they are cutting maple. They have no bark because the logs are debarked before cutting so the slabs that are chipped have no bark. The bark has more ash so I don't know if it would make any difference but will find out next year when I purchase a chipper. I burn any type of wood but want hardwood because of the small size of the chip storage. Don't want to fill the bin up with softwood and go through it too fast and run out. For a test, I ran ceder chips through the burner and could not see any difference other than going through it real fast. Once I even poured five gallons of motor oil in the chip hopper on the chips as they were going in and did not notice a difference in performance.

Conveyor to fill the hopper then it is gravity feed with no auger.

I built mine but if I was going to purchase a rig I would go with the D&G pellet arch. I would have them put a larger feed tube in it so I could put in a larger auger that would handle chips. That way I could still burn firewood if I ran out of chips. It feeds from the back and the front doors are still on the arch. My chip storage bin would have to be moved if I went with that arch. I am thinking about moving and enlarging the bin if I have a good year next spring.

[Mark]

7980

A picture of the chip burner. I fill the hopper about half full or a little more and it is good for about 45 minutes.

[twobears1224]

heres a link to a wood gas site.
http://www.woodgas.net/files/FOA_072.pdf

[Mark]

heres a link to a wood gas site.
http://www.woodgas.net/files/FOA_072.pdf

Mine is a cross draft gasifier. It would be interesting to see someone try a downdraft gasifier on an arch.

[twobears1224]

mark wrote:Mine is a cross draft gasifier. It would be interesting to see someone try a downdraft gasifier on an arch. a downdraft is one of two ways I,am thinking about going..i have plans for the one mother earth news built to run there truck and powerplant.

[Mark]

That is what I was talking about. It does not need to be that complicated since you don't need that clean smoke. You just need to pull the draft down through the coals. Have it up close to the pans so the flame continues under the pans. You want to keep it burning because if you put cool smoke under the pans it can cause explosions.

[Jason Gagne]

I love our wood chip evaporator. We have a 5 X 15 Leader and then added on a 4' X 5' burn chamber, it burns green hardwood mill chips. The system is all automated and works great, and cost $0.35/gal. at 14-15% conc. level. Hard to explain online but your welcome to come take a look.

[wiam]

Jason, Is that a commercial burner or homemade?

[Jason Gagne]

We built our own burn chamber, that was the easy part. Controlling air under and over the fire and the automated chip feed system proved to be the areas that needed the most amount of engineering or tlc. And chips are a local renewable resource that cost us $0.35 to make a gallon of syrup(14-15%conc. level).

[noreast maple]

Got any pics of it and the auger set up?

[wiam]

I can see a trip to Highgate in my future:)

[wiam]

Well it took me 2 years to stop and see Jason, but after stopping there I am ready to start my arch build.

[n8hutch]

Does that mean your going to build a chip burner? I have some interest in this but it seems like a lot of tinkering to get it right.

[wiam]

That is my plan. Wish me luck.

[noreast maple]

I also visited jason this spring and what i had designed was similar to his and his dad. got alot of usefull info from them to help me with the missing pieses to complete mine. I am currently starting to build it now. had to wait for the new sugar house this summer and now that i have that winter tight, its on to chip burner!!!!!!!!! Good luck william, maybe we can compare notes sometime.I also visited another sugarhouse tis summer on the maplerama tour and athough I was impressed with that chip burner ,I still like the simplicity of jasons and the one I have designed .

[noreast maple]

William, what size are you building? Im going with 4x12.

[wiam]

3x12. I have also visited the one you saw during Maplerama. Mine will be closer to Jason's design.

[noreast maple]

Nice size, I like this design because its simple in reality ,but complicated tofigure certain aspects. good luck with your build,I know you will love it.

[noreast maple]

Are you staying with thedrop tube? Im staying with drop tube, going to be a boiling monster.

[mvh1969]

noreast maple,
We spoke last January at the bellows falls VT maple conference about your wood chip arch project etc, please contact me when you are ready for controls to automate your system.

www.imapleinc.com


Sent from my iPhone using Tapatalk 2

[wiam]

Not tubes. I am going with drop flue with same side reversable front. Got a really good deal from Thor Evaporator.

[noreast maple]

noreast maple,
We spoke last January at the bellows falls VT maple conference about your wood chip arch project etc, please contact me when you are ready for controls to automate your system.

www.imapleinc.com
Sent from my iPhone using Tapatalk 2

Yes will do, maybe i will see you this jan 30 at bellows falls again so we can talk more! Thanks for remembering me , I didnt think you would .

[noreast maple]

Ive heard good about thor, good luck and maybe we can chat again.

[mvh1969]

noreast maple,
Yes I will be setup at the Bellows Fall trade show again. See you then.

Mike


Sent from my iPhone using Tapatalk 2