Question about wood

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mapratt

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Jan 12, 2011
45
Coastal Oregon
What determines how "dirty" wood is, when burned - meaning how much smoke / particulates you would get from a very efficient burn (e.g., good gasification unit) of a dry cord of different types of wood?

Some wood is lighter, some heavier. I would expect there to be at least a loose correlation between weight and the amount of heat I could expect to get from it. So, for instance, if I had oak and filled the burn chamber, versus, say, basswood, I would expect to get more heat from the oak, as much because it is heavier / more dense than anything else.

I was kind of expecting smoke production to be basically match the density of the wood I was burning. So, assume well-dried wood, assume efficient gasification unit, get a certain amount of particulates generated for a certain amount of heat generated, even though one would fill the chamber more often with lighter wood.

But it doesn't work that way, eh? What is it about doug fir, for instance, that leads to the only "High" listing for smoke generated, in the chart here: http://www.thefireplacechannel.com/burningwood.html

thanks -
marilyn, who will have to wait until the EPA comes up with its certification criteria before she can get her wood-fired boiler, and who has 60 acres of forest in the Oregon rainforest. i do have a variety of wood in my forest - only some of it is doug fir...
 
What determines how “dirty†wood is, when burned - meaning how much smoke / particulates you would get from a very efficient burn (e.g., good gasification unit) of a dry cord of different types of wood?

Interesting question. Unburned but combustible material should be near 0 in a good gasification unit. I've never seen info on non-combustibles in wood. I would guess most of this would be in the bark, including literally wind-blown dirt embedded in the bark. Other things, like calcium and minerals, I'm guessing might be fairly high (whatever that might be) in wood like aspen, but my guess again is that would be mostly in the bark.

Some wood is lighter, some heavier. I would expect there to be at least a loose correlation between weight and the amount of heat I could expect to get from it. So, for instance, if I had oak and filled the burn chamber, versus, say, basswood, I would expect to get more heat from the oak, as much because it is heavier / more dense than anything else.

Loose connection? Very high connection. Wood weight of equal moisture content has almost everything to do with heat = btu's. Based on a good source I use 6050 btu/lb for 20% MC and 400F stack temperature, in a typical range for wood burned in a gasifier. I also would guess such smoke/particulates as there may be might not be as much related to weight as to bark perhaps, but this is a wild guess.
 
Well at least whoever 'borrowed' the table in the article also borrowed the list of source data attributions, which all date back to the Energy-Crisis-Mother-Earth-Rediscovering-The-Lost-Art-Of-Wood-Burning era. I think it would be fair to say that many of the shade-tree-engineered wood stoves back then did not burn as hot and clean as today's 'EPA stoves' and 'gasification' boilers, and the type of wood would make a difference regarding how hot and clean the fire was.

Douglas fir is more resinous than most and might well be more smokey under sub-optimum conditions. But you are correct in thinking that it should burn same-o same-o in a modern secondary combustion wood stove or boiler.

From anything I've read, BTU per pound of wood fuel dry matter is remarkably consistent from one species to the next. So consistent as to suggest somebody's fudging. This being the internet, that could be because thousands of web pages all stole their data from each other and it all could well lead back to one erroneous study published somewhere once upon a time.

Marilyn said:
marilyn, who will have to wait until the EPA comes up with its certification criteria before she can get her wood-fired boiler, and who has 60 acres of forest in the Oregon rainforest.
Man acquired fire and language and built the polis with law. Now the polis has destroyed language and the law has taken away fire.

--ewd
 
It's all about the water. Some wood holds more water and some wood won't let go of its water. It also matters what part of the tree the wood comes from. The sapwood freshly cut of doug fir has 115% water, more water than wood. The heart wood(center) has 37%, almost ready to burn. Then there is density. The specific gravity on doug fir is .45 on average, less than black cherry. Less dense, less burntime. Some wood, like aspen, is not worth burning unless its free because the ratio is too out of wack, .3 SG and 110%mc. Then there is wood like White Oak which has great ratio, SG of .68 and a average MC of 72% but most of its moisture is tightly bound in cell walls making it very hard to get dry (3 years sometimes) but great for making waterproof wine barrels. In the east, ash, hickory and beech have the best ratio's and readily give up their moisture. Hope this helps some.
 
Some wood, like aspen, is not worth burning unless its free ...

Most of what I burn is aspen, it's off our own land, and well worth the effort to fell, buck, split and stack. But maybe I'm a 150 lb gorilla that needs the workout to maintain my svelte bodily form.
 
"How do you measure the percentage of moisture that remains in wood that you have stacked to dry?"
Easy, All you need is a good scale and an oven. weigh one piece of your wood and write it down. Pop it in the oven set on warm. Weight it every half hour until it stops losing weight. Subtract that number from what you started with and divide it with the dry weight. For example, Say your wood weighed 30lbs to start and 25lbs dry. Your wood contained 5lbs of water so 30-25=5 5/25=.20 Your moisture content is 20% and ready to burn. Don't use a small piece off the top of stack but split a large piece from the middle of your stack in half or quarter to get the best idea what ya got.
Good Luck
 
I guess I don't give much concern. All of my wood is seasoned in rain-covered stacks with good air circulation for at least two summers before burning. With oak I may give it three summers; with small split pine and aspen, one really long summer might do it. But two years is my practice and all is good.
 
Jim,

'Most of what I burn is aspen, it’s off our own land, and well worth the effort to fell, buck, split and stack. But maybe I’m a 150 lb gorilla that needs the workout to maintain my svelte bodily form."

It all burns, burn the wood your with. I have no comment on your svelteness.
 
Pyro - yes, that sounds reasonable.

However, I am building a Grade A dairy. This puts me into the Pasteurized Milk Ordinance - dairy and food safety regulations. Also, since my sheep and goats will spend a few minutes 2x/day with their little necks in stanchions, I am registering as a Confined Animal Feeding Operation.

This means I get to account for every gallon of water I run through my dairy and creamery - how many gallons, on what pasture I spread it (all of which requires infrastructure being built), and I get to account for every cubic foot of deep bedding I have in my barns - again, how much, and on which pastures or gardens I spread it. Also when each activity was done.

The resistance I am getting to installing my wood-fired boiler - I think I'll be ok once EPA comes out with their cert. But right now, the only window I had potentially open was installing the boiler under the new NESHAPS rulings (which has accommodation for small installs like mine, which if one squints at them in a particular way don't look too onerous) - but the unit also has to be tested with Oregon Test Method Number 5. No kidding.

This gets further interpreted to mean, basically, the tester has to use wood from my forest. So, using oak cordwood just won't do, if my mix of woods has no oak, but does have various fir trees (some of which are doug fir, but it's a variety, and the doug fir is better used for other things than firewood), along with other kinds of trees (lots of alder, some madrone, some cedar, etc.).

I'm anticipating having to find a way to ensure the wood I burn is truly dry, as a certification measure for some obnoxious governmental agency (did I say that? Yes I did. The people, in general, are not obnoxious. The rulings are.). Due to convenience when prepping, my woodpile is generally stacked by when it was cut and by species. So I could measure the readiness of an area in the stacks to be sure it's ready to go before popping it into the boiler, once I have a boiler to pop it into. Measuring a sample, and recording on some calendar somewhere for later reporting that the measurement was done, and having at hand an overall procedure documented for same, is the kind of thing I'm aiming at.

I'm also searching for a way to push back on the stupidity of it all. Oregon refused to let me install a GARN because the GARN was tested with oak cordwood. If any properly-dried wood will generate the same amount of particulates based on heat generated, they why the f* do they care? If we have good information at hand, we can better comment on the regulations and rulings being proposed, to try to guide our good gov't agencies away from writing idiotic rulings.
 
Remember that the folks you are likely working with didn't make the rules....they just have to face the public with them. I have been burning spruce in my Garn all summer to heat hot water. It's been down a couple of years and I cut/split it all up this Spring. It is fairly dry, and very light!. Generally, qfter burning for 10-15 minutes, the stack is quite clean. Is it as clean as all hardwood? I actually think I might say no, though sometimes it has been so clean I can't "see" anything....though at other times I could see a bit of smoke. But, there are so many variables here that I can't tell you it is the spruce vs. hardwood.....

But indeed, it sure is a PITA to have to deal with all of these issues. On the other hand, being able to breathe when you are outside with the flock is a nice thing too. I was in Christchurch back in the 90's and literally, in the suburban areas, I was choked out by the smoke from all the folks burning their fireplaces. Now, there was a big inversion layer, so it was massively worse....but apparently this was an ongoing issue. But I kid you not, it was actually hard to breathe, and see, becuase it was so bad.
 
Yup, BPirger, as I said in my post, in the main the *people* I have been dealing with have been fine. Often beyond fine, to very helpful, sometimes even a delight. Some of them only implement the rules others write, some of them have a hand in writing the rules, sometimes interpretation varies by locale, sometimes there are new rules in place that no one has figured out yet how to interpret. In this case, the ruling is new, is bad, and the degree of bad-ness (the howl that went up in response) caught them by surprise. They have been scrambling to try to find a way for at least small commercial enterprises to be able to move forward. They have failed in that effort.

The two things they messed up were: not recognizing the existence of new technology that is actually amazingly efficient, and passing a ruling that treats all of Oregon exactly the same. I agree that a suburban or metro area can be a bad place for a bunch of belching fireplaces, inversion layer or no. Valleys can be bad places, even if more sparsely populated. But there are great swathes of Oregon that are not cities, and are not collection places for particulates.

I have 134 acres, 60 acres in forest. I *can* burn all the wood I want in EPA-certified fireplace inserts and woodstoves. But any time I want to be warm, I have to have a fire burning. I am not allowed to install a wood gasification boiler with a huge thermal store, which would allow me to burn wood once every few days at a temperature that obliterates the wood and has amazingly few particulates - 'way less than the inserts and stoves - even while it's burning, and would need to burn so much less often.

So in the effort to reduce pollution, in my case they are significantly increasing it. It's stupid. But I thanked the nice lady who was working with me at the Dept of Environmental Quality, for her attempts at helping me.
 
ewdudley said:
Man acquired fire and language and built the polis with law. Now the polis has destroyed language and the law has taken away fire.

--ewd


Polis in its true full contextual meaning as intended by the Greeks, was only actualized by fully involved citizenry...thus the term "idiotes" which in Greek means "private, self involved" and not involved in the politics of the "polis". Ergo our word: idiots! To the ancient Greeks, these were the people NOT involved in their "polis" and they were considered ,literally, idiots("idiotes").

To the citizens this was anathema and it led to..well, to what our founding fathers so wisely had warned us about, which is the state we are living in today, specifically(as Elliot suggests), the Polis controlling us, as opposed to us (the citizenry, free creators of the polis) controlling it!.. Some bones are rolling under there somewhere..

Plato also mentions Socrates' words in a related paradigm: "The unexamined life is not worth living".
On the surface, this is may seem generalized, but the root of it suggests introspection, which in turn leads to the overall understanding of human functionality and ultimately the social aspects of our civilization and Polis... and worst the assumption or loss of control of such.

Sure I digressed from the subject, but this too, as Elliot VERY WISELY commented upon, holds water and these days I feel it to be very relevant

Apologies, just had to throw that in the soup, especially since I am revolted at the amount of taxes I just sent in and the local taxes I need to pay in 2 weeks.

SK
 
Very well said SK, and I agree, even though I suspect we may be on opposite sides of the aisle....
 
bpirger said:
Very well said SK, and I agree, even though I suspect we may be on opposite sides of the aisle....


Thank you kindly Sir,
but I have resigned myself to the fact that there is no difference between the two sides of the isle....and I subscribe to neither, nor tea party, nor anything else, even though I would dare to admit I may veer towards libertarianism in certain principles, but I am for health care for all with the public option.

It is my suspicion , the illusion of choice is well entrenched and has been accomplished via the degradation of values, the systematic sub-standardization of education and it's contextual method of critical thinking and analysis; and worse have we ever wondered what happened to CIVICS classes in school?????

The silver lining seems to be consistently lost in extremism & ignorance ..a magical combination for controlling masses. Historical references abound.

Waaaaaay too serious, but I can not sleep due to boiler matters..so this may make it tangentially relevant ...

SK
 
My boiler is running fine, but I can't sleep with the way our nation is heading.... Hope you neck of NEPA is dry...I know many folks aren't. But I couldn't agree more...the lack of interest/attention paid to the world really does allow the masses to be so easily controlled. Buzz words, quick chirps, they seem to be what folks cling too. Actual reading, understanding, comparison to history, those are all rarely found. I don't know what it is going to take to redirect...but I fear it is going to get worse before better. Just three years ago the world was almost brough to its knees due to a financial debacle...and nothing has really changed. I just completely fail to understand how that can be. Though I'm not surprised. Massively disappointed, and concerned, but not surprised. But with concern for getting Marilyn's this thread canned to the Ash can, I'll stop!
 
Not sure at what point moderators become concerned that a thread has gone viral ;-)

I agree with the worries above. I am also worried about a generation of young men with nothing to engage their minds, nothing to do, in so many areas of the world. All around the world, such large numbers of young people unemployed or under employed. Cutting back on education / making universities more expensive, and in so many areas even with the degree there are no jobs.

Into this pool of gasoline, toss the tinderbox of the ease of swiftly organizing, via the social media.

It will be interesting to see if anything comes of it, but there is a call out for hopefully peaceful demonstrations all around the world, specific locations in major cities, on October 15.

Now, that's truly off-topic...
 
bpirger,

" Just three years ago the world was almost brough to its knees due to a financial debacle…and nothing has really changed"

Some things have changed; we are trillions more in debt now and we have thousands of pages of new legislation protecting and insulating the elite. Imagine all the change in store for us after financial debacle 2.0.

I am looking at buying a Wallenstein FX90 winch this year, I take it you like yours. Is it easy to take on and off your tractor? That short drive shaft looks like it might make it tricky.
 
I'm very pleased with the winch. I have no comparison to compare against, as I have never used any other. Looks and feels rugged. It was easy to put on but I haven't taken it off yet...though I see no reason why it would be difficult. I had to cut the driveshaft, but that seems to have gone fine. I have had no problems at all with the winch, though I just got it in the Spring. We did bring in about 10 full cords this Spring....so much nicer to drop and drag everything to the woodshed rather than carrying round after round in the wagon behind the ATV. A good snatch block is essential as one almost always has to redirect the pull around other trees, stumps, etc. unless the felled tree is right on the logging road. I got one from Bailey's listed with the "lewis winch". I think it was $75 or so....very heavy duty and easy to take on/off. I can see how it would be nice to get one of those blocks that automatically release the line when the log reaches it...but they are more like $250 or so. I've had my wife helping in the woods, apply the snatch block, so it has been OK. You do make constant trips from the tractor out to the tree being pulled in, so if you are working alone, it might be worth the extra just for the speed increase over the years.
fast
One guy who has seen it has a Farmi 351 and he said the FX90 was much bigger, heavier, and looked to be better made. It is a bigger unit, but the cost is just about the same as the smaller Farmi.
 
bpirger said:
My boiler is running fine, but I can't sleep with the way our nation is heading.... Hope you neck of NEPA is dry...I know many folks aren't. But I couldn't agree more...the lack of interest/attention paid to the world really does allow the masses to be so easily controlled. Buzz words, quick chirps, they seem to be what folks cling too. Actual reading, understanding, comparison to history, those are all rarely found. I don't know what it is going to take to redirect...but I fear it is going to get worse before better. Just three years ago the world was almost brough to its knees due to a financial debacle...and nothing has really changed. I just completely fail to understand how that can be. Though I'm not surprised. Massively disappointed, and concerned, but not surprised. But with concern for getting Marilyn's this thread canned to the Ash can, I'll stop!

Actually my boiler is running great, it is my chimney that is giving me beef!!! But i think I have it figured now and almost done with it.....
NEPA got hammered man....both roads to my house were completely gone at different section....one was completely washed away..and the other was covered with mudslides.. Thankfully our house fared well,, no water and no trees down, around it.

Off topic...again the mods are going to hammer me...but yes you are right, we are fastly sinking...and the money elite, know exactly what they are doing.The elimination of the middle class is a catalyst in the goal. Serfdom people and very rich only seems to be the end game. The bankers got bailed out and believe me they are sitting on that cash. THE MARRIAGE OF CORPORATIONS AND GOVERNMENT ON A GLOBAL LEVEL IS KILLING US and it leads to fascism.

Some things have changed; we are trillions more in debt now and we have thousands of pages of new legislation protecting and insulating the elite. Imagine all the change in store for us after financial debacle 2.0.

No one is bailing me out..I have a small business and I struggle everyday. I have accounts open from BIG NAMES and I cant get paid...was told in no uncertain terms that their legal department will squash me and I will wind up spending more on legal fees that what I am owed. This is NOT an isolated case. My goal in turn has shifted to growing more of our own food, including grain and baking, raising live stock and working with my friends locally in farming, and food production and sharing. The only problem there, is high taxation(real state/school taxes up 250% in the last 4 years) and regulation(nothing wrong with guidelines but excessive legislation for the sakes of monetary gain is absolutely vile). My wife and I are gravely concerned with what our children will have to contend with. But at least they will have some knowledge of basic survival and LOTS OF WOOD TO SPLIT AND BURN(back on topic....)IF THEY DO NOT TAKE THAT AWAY AS WELL.

SK
 
Yes, SK, back to topic (sort of) - in Oregon they are taking that away too. Which is particularly ridiculous given the opportunity for energy independence here, since it's rather easy to grow a tree in this climate.
 
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