Burning Waxed Cardboard

[stevepipkin]

We burn hardwood in a 2x8 Leader evaporator. What do you think about mixing in wax coated cardboard? Does anyone have an opinion or experience with this fuel source?

The waxed cardboard boxes are produce boxes from my business. The wax is food grade, meaning it's from plant sources. We are trying to cut our waste stream at work and this seems to be a good use. From the bit of online research I've done, I've learned that pressed fireplace logs are largely made of compressed waxed cardboard. Most of these are petroleum based, however there are some made entirely from food grade waxed cardboard, Hotlogs and Envirologs. They burn cleaner than the petroleum based logs and 60% cleaner than wood. They aren't recommended for wood stoves because they burn too hot.

The U of Vermont did some research concerning alternative fuels indicating that the addition of waxed cardboard pellets to grass pellets significantly increased the heat produced in a controlled setting. The best heat production occurred at a ratio of 2.5:1, grass pellets to waxed cardboard. They also indicated that the waxed cardboard had a lot of BTUs and burned very cleanly. The temperatures with waxed cardboard were pretty high, 675F compared to 398F with grass pellets alone. Is that too hot? (everybody hates a scorched pan)

Finally, I found out that virtually no creosote is produced by burning waxed cardboard.

I am concerned that incomplete combustion of the gasified wax could lead to wax deposits in the the flues and in the stack. That would be a mess in addition to a potential stack fire. The U of V did say it was a very clean burn......hmmm.....

I'm trying to keep cardboard out of the landfill and sure would appreciate your knowledgeable comments.

Thanks, Steve

[jrthe3]

i work for a whole sale food ware house we had a dumpster just for cardboard waxed or not i is emtyed every week and sold the money we get for the card board pays for both dumpsters trash and cardboard and still end up with cash in hand i think i would look into selling it to be recycled befor i would burn it

[802maple]

I don't know anything about waxed cardboard but when I was selling Maple Equipment I used to get tubing in Card board boxes that were over a inch thick and also they would come on cardboard pallets and I would cut them up so that I could handle them much the same size as firewood. They would last as burning wise about as long as dried popular but would put out the most amazing heat. I would save them for a big boiling day because I never saw anything boil as hard as they did. When your pans get coated on the bottom it is due to not getting enough air. Even with tires (which is illegal most everywhere) you won't get a coating if you give it enough air, which is nearly impossible with any manufactured evaporator.

[mfchef54]

I would agree with 802. It would seem to me as long as the fire is getting plenty of air they should burn well. As far as selling the waxed cardboard here in NY the companies won't take it and the transfer stations tell you to throw in in the regular bins.

[peacemaker]

i got a bunch of pallets last year from sears there tractors came in them they where poplar covered in cardborad i cut them like 802 said and man did they burn hard ...

[Haynes Forest Products]

I would do it the high heat will take care of any build up. I have a fellow producer that loves to burn a small amount of shingles as he boils. My only concern with cardboard is having small peices fly out the flue pipe and go airborne.

[peacemaker]

dont you think with the heat in the stack it wouldnt make it out the end ...

[Haynes Forest Products]

I think cardboard has a habit of burning into large sails and floating up and out but a screen on the stack end will end that problem. I only say this because when I fired with wood there were times that I had some big sparks and chunks out the stack. you would think Casey Jones was firing the rig.

[Haynes Forest Products]

I think cardboard has a habit of burning into large sails and floating up and out in ash form but a screen on the stack end that problem. I only say this because when I fired with wood there were times that I had some big sparks and chunks out the stack. you would think Casey Jones was firing the rig.

[Brian Ryther]

As a rule we do not put anything in the arch other than wood. I start the fire with oxy/act torch. If you burn paper the loose ash will stick to your flues and act like insulation.

[WESTVIRGINIAMAPLER]

Brian,

You bring up a different point that I have never heard before. I always used shredded paper. Anyone else have any opinions on what Brian has stated. Not saying he is wrong in any way, just curious to hear what others say.

[OGDENS SUGAR BUSH]

i have always started my fires with kindling and propane torch, then fire with wood or pallets only

RICH

[partsrus1974]

If its not metal its SAP Wood!!LOL

[maplwrks]

This will make you either wet your pants laughing or make you shake your head in disgust....but here goes---Don't try this at home!
Before venturing out on my own, I boiled for a sugarmaker here in town. His theory was this- If it fits in the door and will burn, In it goes! I have burned RR ties, tires, construction desbris, silage tarps, recyclable plastic bottles, a fiberglass bathtub and a 14' wooden row boat! Sometimes we even burned soft and hardwood slabs. If any of you live near a printing plant, the best fuel I EVER burned was the cardboard tubes that paper is wound on. The wall thickness was 1/2" and man, you can really make syrup on them! They would burn with a green flame, I guess from the glue in them. They created no ash and all that was left after cool down was a "clinker" on the grates. The fella I was boiling for would sneak into the sugarhouse and throw 2 tires into that 5x16 and run outside to watch the black smoke roll! He would here me start to swear and would just giggle,I would need to flood the syrup pan to keep it from burning, but you would make a lot of syrup!!

[mfchef54]

I take it the feed door was air tight?!LOL

[Haynes Forest Products]

A farmer friend starts his year out burning feed bags full of old sap and mainlines that the squirles chewed and man things roll and its like sending out smoke signals. I put a old roll of tar paper in the camp fire once boy that sent them packing.

[maple flats]

I've burned trash wood, and cardboard after the fire is going good. I never see any smoke, the exhaust is clear. I do not burn plastic nor rubber, never tried and never will.

[markct]

at a recent seminar with a guy from university of vermont i believe it was, he mentioned how he knew of a sugarmaker that destroyed his pans by burning tubing, it ate holes in the stainless, after some research they found it was something created byt the pvc burning but i forget just what it was chemicaly, but still i dont think i would try it on my pans!

[Russ]

In our early years, brother Ryan had access to waxed cardboard liners used to separate large blocks of cheese. We'd toss these in our multiple small cookers (4) and have jets of flame coming out the 24' stacks. It was awesome and they burned like the fires of hell. I would only use them with a hot fire and lots o' air; wax smokes a lot when not completely combusted.

[stevepipkin]

Thanks to all for your responses. I will experiment this year and report my findings. This is a great site. I'm gonna like it here.

[dano2840]

Ok here goes ive never burned any thing like tires before but my dad is a bee keeper and some times we get a hive where thinkgs well go wrong, we save the frames and THEY MAKE THE SAP BOIL LIKE HELL, also on our farm we wrap our hay and the cardboard cores from the rolls of wrap are the hottest burning things i have ever seen.

[jrthe3]

My dad works in a wood shop and brings me home 55 gallon drums full of scrap hardwood trim you fill the fire box with that stuff you have turn the blower off or there will be a 8 foot flame out the top of the stack i will take a pic and post it this season kinda cool looking

[stevepipkin]

This is what i found out about burning waxed cardboard:

We rolled the waxed cardboard into "logs". They are great for starting a fire in the box. I put a couple on the bottom of the kindling pile before lighting the fire. It starts a strong fire quickly. I was able to go from striking the match to initial boil in the evaporator pan in 35 minutes.

In order to more fully combust the wax, I threw the wax logs into the fire box after the fire was fully established. They burned great. You could see the boil jump when I threw a couple of babies in there. I threw a bunch in at one time and they all burned like hell.

The first problem I noticed was when I reloaded the firebox after burning some of the wax logs a small amount of light weight paper ash came floating out of the fire box. Some of this light weight paper-like ash would land in the evaporator pan. I didn't like that.

After combusting, a wax log would look like a roll of toilet paper. It didn't fall apart. The spent log would sit in the firebox, occluding the air flow until I knocked it down with a fire tool. Unlike denser wood ash, the cardboard ash did not fall easily through the grates in the bottom of the firebox. I constantly had to stir the fire to get the ash to fall through the grates. I didn't like that.

For me the bottom line is: not worth the trouble. If I had an unlimited free source of wax "logs" I would use it to augment my current wood burning fire efforts. As it stands now, the effort per btu to roll the waxed boxes into logs is the same per btu to saw and split hardwood. Those things being equal I cast my vote against waxed cardboard.

I will keep some around for starting fires.

Steve

[WESTVIRGINIAMAPLER]

Sounds like they would work a lot better in an airtight arch but would probably blow a lot of ash out of the stack.

[nymapleguy607]

My favorite thing to boil with is old dried black locust fence posts. I put the air right to it and it sounds like I have a freight train running by the sap house

[WESTVIRGINIAMAPLER]

The old locust fence post and old fence rails all burn about the same and I wish I could burn them for the entire season.

[RileySugarbush]

That's what I burned last year, lots of old locust rails. Great stuff!

[stevepipkin]

Brandon said:
Sounds like they would work a lot better in an airtight arch but would probably blow a lot of ash out of the stack.

If it disintigrated and fell through the grates it would better in an airtight arch. I thought that the turbulence in the fire box would blow it up the stack or into smaller pieces of ash, but no, it just sits there occluding the airflow.

[stevepipkin]

One last note about burning waxed cardboard. When combusting it made a lot of black smoke, even in a hot firebox. That black smoke was partly combusted wax. It occluded the flue pretty quickly. I'm not a fan of climbing on the roof to clean the flue. It probably isn't very good for air quality either.

I'm sticking with wood.

[vtsnowedin]

You guys have me beat. The old man talked about cutting model A tires into quarters with an axe and finishing out the season making tobbaco sugar but he said it sooted up the drop flues something awful. Worst I've ever burned was some demolition wood with multiple coats of paint on it and a few sofa cushions. I've got too much good volunteer sugar wood standing around waiting to be cut to fool around with anything that's going to put up a black plume and irratate the flatlander neighbors.

[Michael Greer]

I cut up waxed boxes and have a handful of "sticks" in my kindling box near every wood-fired device. There is no better fire starter. I can't see doing any real heating with waxed cardboard though.