Wood With A High Iron Content

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wooduser

Minister of Fire
Nov 12, 2018
679
seattle, wa
I just discovered this website and have been having fun posting on wood stove and gas fireplace threads.

I'm a firebug ---- I've heated with wood for thirty years and am a retired gas furnace and gas fireplace repairman.

I saw an earlier thread asking about the best firewood.

Well, people have different styles, but MY idea of the best firewood is that which I can get for FREE!

And that's what I do. I live in a residential area that buts up against a light industrial area, and there are several businesses that yearn to have someone come by to pick up their bins of scrap wood so that don't have to pay fancy prices to have it hauled away.

So that's what I've been doing for a wood supply the last thirty years.

Much is 2x4s and other scrap lumber. Some comes as shipping containers which can be hardwood from Asia.

Mostly what I get is some kind of lumber with nails in it which I can take home in my van and cut to suitable length with my table saw or circular saw, for long pieces.

Must keep stoking that stove with a lot of wood though ----none of your oak and such finds it's way into my wood pile.

And it's wood that usually has a high iron content, from the nails that are in it.
 
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Heads up, most pallet wood has so called galvanized coated nails. Many of the nails come from China and the so called galvanizing sometimes contain other waste metals. The temperatures in the fire will vaporize the coating quickly and send it up the stack. Lead is pretty much to be expected but cadmium and chromium also pops up. At a minimum it will kill a catalyst. It can create a fairly toxic plume when burned so folks down wind can have long term health effects. Definitely throw away the ashes and dont use them for soil conditioning as its adding toxic metals to your soil.

The other aspect is there are a lot of non registered toxics applied to pallets and crating due to export regulations. These can create some real toxic fumes like furans and dioxin.

I did a large biomass project in NC at one point and the military had loads of pallets and shipping containers available for free for fuel. Between the glues in the chipboard and the metals in the nails we couldnt use the fuel unless we installed an electrostatic precipitator. The strange thing was we could burn railroad ties.
 
I see from reading comments in stove manufacturer's operating instructions that the use of scrap wood in modern stoves can be frowned upon. This seems especially the case with catalytic stoves, where the fear is that chemicals in scrap wood may degrade the performance and longevity of the catalyst.

Does that sound right?

This would be an argument for keeping my old uncertified stove in operation. It has been dining on scrap wood for decades.
 
I see from reading comments in stove manufacturer's operating instructions that the use of scrap wood in modern stoves can be frowned upon. This seems especially the case with catalytic stoves, where the fear is that chemicals in scrap wood may degrade the performance and longevity of the catalyst.

Does that sound right?

This would be an argument for keeping my old uncertified stove in operation. It has been dining on scrap wood for decades.

You would want to screen out all the plywood, OSB, treated wood, painted wood, urethaned wood, and galvanized nails.

Honestly, you have to breathe the air around your house, so you should screen that stuff out for your old stove too.
 
I burn a fair amount of pallet wood too usually as kindling but sometimes bigger oak 4x4's too. All kiln dried, nails pulled. Sometimes I'll throw pieces in which still have nails. Would be willing to bet if you were to test ash for heavy metals/contaminate it would be well within limits. I base this guess off our dust collection test results at our sandblast shop where we blast a huge variety of metals and coatings. All dust samples which we typically take twice a year stay well within safety limits of all contaminates. Long story short a few nails isnt gonna hurt a thing in an old/non cat stove....in my opinion.
 
Back when I was in the pulp and paper industry the facility I worked for used chlorine for bleaching wood pulp. The facility had a scrubber on the exhaust vents where the bleaching occurred and a small amount of chlorine would eventually make it into a recovery cycle and eventually burnt. One of the byproducts was Dioxin in trace amounts. I think the measurements were in the single digits of parts per trillion. Dioxin got a legitimate bad reputation as it was used in large quantities by the US government in Vietnam war. Its environmentally persistent and a major health issue for both sides of the war. New regulations were passed in the 1980's requiring pulp and papermills to be close to "non detect" for dioxin which I believe meant if it could be detected at all, the facility had to upgrade. This cost the industry tens if not hundreds of millions for each mill and was a contributor to the industry moving offshore putting tens of thousands of employees out of work.

Dioxins are formed whenever chlorine is burned, wood has some chlorine in it and wood from areas with salt water have even more of it. When burnt wood will also give off Dioxins and major forest fires are a contributor to the baseline. One of the things we learned during having to deal with dioxin at our mill was that burning municipal waste in a boiler also contributed Dioxin to the air mostly due to combustion of PVC plastics which is used in toys and packaging. The typical rubber ducky is made with PVC. Dioxin formation varies with combustion temperature and a hot fire like seen in a pulp mill recovery boiler or municipal waste burner is quite low while poor poor combustion leads to very high levels. When the state ran the numbers for the total dioxin generated by our pulp mill and a municipal waste burner the total numbers were quite low. What was quite surprising is the state tested a couple of household burn barrels and they came to the conclusion that a few burn barrels burning typical household waste could exceed the total Dioxin produced by the industrial units. The state actually banned outdoor burning of waste although enforcement is spotty.

This is the case with several toxics, burn them hot in a licensed facility with emission controls and its not a major issue. Burn it uncontrolled in a small source like a wood stove and it becomes " a death by a thousand cuts" situation where each producer contributes just a small amount of environmental toxins but when its aggregated it becomes a major source. Many industrial facilities have to landfill coated wood and construction debris have to be segregated into coated and uncoated with the coated wood sent to licensed facilities.

Therefore it comes down to if someone doesnt care about their family and neighbors and future then they are going to burn wood with potential contaminants because its cheap or free. These may be the same people that dump motor oil in their backyards or dump trash on the side of the road in a ditch. Its not just individuals, the current administration has adopted the "who cares" approach to air toxics and water pollution and put industry lobbyists in positions of authority. to dilute the regulations. In this case, greed and political power exceeds any long term stewardship responsibilities. This is not just US its worldwide. The bummer with environmental toxins are they are slow killer in adults. Children on the other hand suffer the worst, some are impacted in the womb and are born with birth defects or still born and some just have a shorter life due to childhood cancers.

Some folks do not have choice where their economic situation means they have to burn what they have, others are uneducated and dont know the damage they are causing and some just do it thinking they are sticking it to "the man" even though they are ultimately "the man". We can try to educate the first two groups but all we can do it pity the last group and support regulations to ban the practices.
 
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wooduser, georgepds replied to a thread you are watching at Hearth.com Forums Home.

Wood With A High Iron Content
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What I see is that people burn what they have. The red oak folks tend to look down on those burning pine, or whatever.

I will continue to burn scrap wood and consider it a public service to do so.
 
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wooduser, georgepds replied to a thread you are watching at Hearth.com Forums Home.

Wood With A High Iron Content
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What I see is that people burn what they have. The red oak folks tend to look down on those burning pine, or whatever.

I will continue to burn scrap wood and consider it a public service to do so.
If you are burning plywood and painted or stained stuff i doubt your neighbors see it as a public service. If it is clean scrap with some nails i dont see an issue.
 
Usually it's pretty obvious what scrap/pallet wood is good to burn. We get a lot of pallets at work and very rarely do I see any that are treated, so it becomes easy to distinguish.