can it be to dry ? i have some wood that is 10% to 15% . i saw it said to burn cord wood only not kiln dried could this wood be to dry? what percentage should you not bun in the lower range or is it all good below 20%
About to pull the trigger on a blaze king princess 32
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Highbeam
Minister of Fire
1. I cut every round to a measured 16" using this cool tool called a mingo marker. It's fast, accurate, and easy. This size works great for both of my stoves and also allows me to help out or sell to other people. It's a standard length for most stoves. The diameter is a bit trickier. You want to be able to fully fill your firebox so you need a mix of split sizes but mostly big ones. I have increased the split size over the years to about 6" as measured across the longest end dimension. I don't think anybody does 10" "diameter" except for the occasional odd ball split that you intend to fill around. That's just too big. Another way I split is that I want to be able to one hand each split and fling it onto the pile. If it takes two hands, then that's too much! Other than the king firebox, there is only room for two rows of splits so I think you are better off trying to pack 6" splits tight than you are trying to squeeze in a yule log and then put a bunch of 2" splits around it.
2. I didn't use the ash pan for a long time. I use it now. It's cleaner and results in less ash in the room. The ultra model ash pan is reasonably large. Leave an inch of ash in the bottom, things burn better. I can get about 2" of ash depth into the ash pan with each fill.
Highbeam
Minister of Fire
@Poindexter has done some ultra dry wood experiments with a solar kiln. In my climate, the driest I can naturally get wood is about 13% which is what I get with softwood after about 2 years. If your 10% wood is just air dried then I would check your measuring methods and then burn it.
I believe what would happen with popcorn fart dry wood is that it will off gas fuel quicker than the cat can eat it and lead to smoke emissions which is wasted fuel. This doesn't sound dangerous but nobody likes a smoking stack or wasted fuel.
I split some of my pine open other day, and I’m reading 0%. So, either my meter is off/wrong, or it’s not and it is 0. Wood burns just fine, haven’t noticed any ill effects (smoke, waste, shortened burn times etc).
Poindexter
Minister of Fire
The lower limit for me is 13% MC. @WV Homestead , @MMH
The sweet spot for my install is 13-14-15%, dry enough to light off quick on hot reloads, dry enough to get up on the combustor quickly during regulated cold starts, but damp enough to still give long burn times.
12% and under doesn't work good for me. Lights off like a torch, burns hot and burns really fast. I accidently kilned eight cords down to 10% MC a few years ago. It was brutal. My local dealer and BKVP and I worked it out. If you have this problem run it by Chris before you proceed. If I can't have 13-14-15% fuel I would rather have 16-17-18% than deal with <12again.
Even in Nevada I doubt zero percent actual, more likley below the ideal range for the meter and it doens't know what else to say. You can look up your Equillibrium Moisture Content from the US Forest Service. I just found an online calculator too, here: http://www.csgnetwork.com/emctablecalc.html
Figure out what your average temperature and humidity at your house has been for the trailing 14 days or so - ass/u/me starting with well seasoned wood- and your caluclated EMC should match your moisture meter pretty close if your met data is accurate. Depends on your split size of course, bigger splits and thicker lumber take longer to equillibrate.
The sweet spot for my install is 13-14-15%, dry enough to light off quick on hot reloads, dry enough to get up on the combustor quickly during regulated cold starts, but damp enough to still give long burn times.
12% and under doesn't work good for me. Lights off like a torch, burns hot and burns really fast. I accidently kilned eight cords down to 10% MC a few years ago. It was brutal. My local dealer and BKVP and I worked it out. If you have this problem run it by Chris before you proceed. If I can't have 13-14-15% fuel I would rather have 16-17-18% than deal with <12again.
Even in Nevada I doubt zero percent actual, more likley below the ideal range for the meter and it doens't know what else to say. You can look up your Equillibrium Moisture Content from the US Forest Service. I just found an online calculator too, here: http://www.csgnetwork.com/emctablecalc.html
Figure out what your average temperature and humidity at your house has been for the trailing 14 days or so - ass/u/me starting with well seasoned wood- and your caluclated EMC should match your moisture meter pretty close if your met data is accurate. Depends on your split size of course, bigger splits and thicker lumber take longer to equillibrate.
jetsam
Minister of Fire
Yes, you can't operate the stove exactly the same as you would with dry wood.
You know most of the story already from operating old stoves- it is harder to start from cold, need to burn higher to burn clean.
The new twist is that the new stove gives you the ability to turn the air down to almost nothing. If you have a stove without a bellyful of hot coal, and you light up a load of damp wood and crank it way down, the cat is going to drop out fast and you are going to have significant creosote accumulation from just one load. (Also poor efficiency.)
You can still burn low with poor wood, but you want to start off your low burn with a real hot stove (this helps cook some water out too), and keep the brush handy. I'm not joking when I say you should sweep once a week until you get a feel for how often you should sweep. (If you are crudding it up that fast, your cat is dropping out and you need to start burning hotter.)
Is wet wood bad for a cat? That's not a yes or no question. Here's my thoughts:
- Water vapor in and of itself is harmless to cats.
- Water vapor can carry minerals, and mineral depositation and masking is a cause of poor cat performance. A vinegar bath and a rinse with distilled water can reverse some masking, so I don't see this as a big deal personally. But your average user isn't going to maintain their cat, so it may be an issue for most people.
- I'm only mentioning this one because it's often mentioned, but I feel like it's an edge case, and not one that will ever be an issue for me: Thermal shock. Steel cats don't care, but ceramic substrates can crack if they are cooled suddenly. The most common example would be someone opening the door without unbypassing the cat, 80° air hits 1300° cat. In theory you could slap a split with an inch of snow on top in, unbypass, and shock your cat with cool water vapor. I guess you could do that, but it seems like most people wouldn't, and also that the far more common hazard would be forgetting to unbypass before opening the door.
Nealm66
Minister of Fire
Probably worth the effort in my case if I compare the cost of free wood to press logs. I’m just way too deep into this thing after purchase and install, like around $8000 , to be tempted and have something go awry. I justify the press logs in a way since I thought I was going to have to buy a pellet stove
Yeah i agree with this, I doubt it’s actually 0% with the way the wood/stove behaves I’m guessing the moisture is down to or close to the fudge factor of the meter
stoveliker
Minister of Fire
I'm not trying to be annoying, but water flying through a cat (or flue) does not need to be 212 F. In fact it won't be steam (liquid droplets) but water vapor (gas, I visible) - that can easily be 1000 F (water molecules only decompose - into the explosive hydrogen and oxygen mixture...- at 3000 - 4000 Kelvin). Water vapor (or gas) can be very hot. So it's not guaranteed that "cold steam" hits the cat. This would depend on how much it warms up, which will most likely be more than 212 F.
Regardless, the heat capacity of water is large, so a lot of energy is needed to get water (liquid! I'm not sure about the heat capacity of water has) hot. So dry wood surely is better.
It's going to be about 212F because if it was any hotter more water would be flashing off from the wood. More heat in the firebox would just flash it faster, obviously not all the heat is used for making steam but I'd be very surprised if you could get the flue temps of sopping wet wood over 300F.
My dad used to argue this concept with my mom all the time, she wanted pasta to cook faster so cranked the heat to a very rapid boil, she couldn't understand that with a very slow boil or rapid boil the water was both 100C or 212F, the only thing that changed was the amount of energy wasted in off-gassing steam.
Poindexter
Minister of Fire
A couple finer points here.
First, don't conflate combustion temperature with ignition temperature.
I am going to start down a rabbit hole, but I have a plan. The smoke point of canola oil is about 600dF. If your skillet is hot enough for the oil to start smoking, its about 600dF. The flash point of canoila oil, where it spontaneously bursts into flame in the presence of oxygen without a spark, is about 700dF.
The combustion temperature of hydrogen in the presence of oxygen is indeed about 950dF, but the ignition energy of hydrogen/ oxygen mixtures is only 0.02 millijoules. One joule is 1/3600 of a watt hour. a millijoule is 1/1000 of a joule. Hydrogen/oxygen mixtures are very very easy to ignite.
Gotta go. energy of vaporization.
First, don't conflate combustion temperature with ignition temperature.
I am going to start down a rabbit hole, but I have a plan. The smoke point of canola oil is about 600dF. If your skillet is hot enough for the oil to start smoking, its about 600dF. The flash point of canoila oil, where it spontaneously bursts into flame in the presence of oxygen without a spark, is about 700dF.
The combustion temperature of hydrogen in the presence of oxygen is indeed about 950dF, but the ignition energy of hydrogen/ oxygen mixtures is only 0.02 millijoules. One joule is 1/3600 of a watt hour. a millijoule is 1/1000 of a joule. Hydrogen/oxygen mixtures are very very easy to ignite.
Gotta go. energy of vaporization.
Poindexter
Minister of Fire
or latent heat of vaporization. Just like you can have both ice and water in the same glass at +32dF, you can have an open pot of water at +212dF with both water in the pot - and vapor also at +212dF rising out of the pot. It takes a fair bit of heat to convert liquid water to water vapor once you have it at +212dF but google willhave to do for now, I have a thing to go do. Peace out.
stoveliker
Minister of Fire
Yes, cooking only goes higher when under pressure (and lower in the mountains). You are correct, water evaporates at 212 F. Regarding the cat, you are only correct provided that the (low density) water gas does not gain any temperature during its travel through 600+F gases in the firebox under intense IR radiation on the way to the cat. I guess the question is how much gain there would be in that phase following the evaporation step from the wood.
jetsam
Minister of Fire
If you're new here, we've learned over the years that Poindexter's elaborate solar kiln/woodstove setup is really just a (successful) plan to get his wife to wear less clothes around the house.
stoveliker
Minister of Fire
correct, but before latent heat is needed (evaporation), the heat capacity (energy needed to raise the temp by a certain amount) of the liquid plays a role (both eating up energy, hence use dry wood). However, after having spent energy on heating (to boiling) and evaporation, i.e. after the vapor has taken off, there is only the heat capacity in the gas phase, and the energy input into that water gas that determines the temperature of the vapor reaching the cat or flue.
In the gas phase (after it's been evaporated), it takes half the energy to raise the temp of the water vapor by a temperature unit as compared to in the liquid phase. Given the temperature of the gases in the firebox, and depending on the draft (gas flow speed in the box), and the turbulence (path length), the temp of the water vapor reaching the cat will be significantly higher than its boiling point.
But I think the experiment of measuring temps in front of the cat as a function of MC (with the T-probe being shielded from the IR emanating from the cat) has not been done.
So this subject will remain an exercise in theorizing
.
Highbeam
Minister of Fire
Bringing back good memories from thermodynamics classes about steam tables and turbines and etc. superheated steam, saturation.
My daily bread and butter. Someone has to keep the lights on, after all ;-)
jetsam
Minister of Fire
So since we have all you phase experts in one thread, help me think about a stove problem.
A tree takes up groundwater, the water has minerals in it. We dry the tree out some and burn it while it still has significant water content.
My assumption is that burning wood emits both water in the gaseous phase, which probably contains almost zero minerals, and also aeresolized water, which has whatever its original mineral content was.
If the stove is working right, both hit the cat, the airborne water gets vaporized, and the minerals may stay on the cat.
Also, the water that was evaporated during drying and the water that was vaporized during burning both left their mineral content in the wood. Some part of that becomes airborne and goes through the cat and perhaps stays on the high-surface-area superstrate.
We all know that our cats decline in performance over time. A catalyst by definition is not consumed by the reactions it facilitates. We are pretty sure one reason for the decline is mineral masking of the catalyst, because 1) experts tell us so, and 2) a vinegar bath definitely perks up a sad cat.
(The other major reason I've heard is that the substrate gets a wash coat of very high surface area aluminum oxide, and the catalyst is then deposited on the wash coat. If the wash coat overheats, it softens and loses surface area.)
....so to what extent will drier wood actually lower the mineral content of the air that hits then cat? (And is burning wood actually putting out water vapor AND aeresolized water? It seems like it should be.)
Obviously less water vapor equals less airborne minerals, but minerals must get airborne as flying ash and such too.
It also seems obvious that drier wood will, all other things being equal , mean higher firebox temps, which means more water vapor and less aeresolized water.
How much cat mineral depositation is a result of aeresolized water being evaporated, and how much is a result of smoke and ash passing through?
A tree takes up groundwater, the water has minerals in it. We dry the tree out some and burn it while it still has significant water content.
My assumption is that burning wood emits both water in the gaseous phase, which probably contains almost zero minerals, and also aeresolized water, which has whatever its original mineral content was.
If the stove is working right, both hit the cat, the airborne water gets vaporized, and the minerals may stay on the cat.
Also, the water that was evaporated during drying and the water that was vaporized during burning both left their mineral content in the wood. Some part of that becomes airborne and goes through the cat and perhaps stays on the high-surface-area superstrate.
We all know that our cats decline in performance over time. A catalyst by definition is not consumed by the reactions it facilitates. We are pretty sure one reason for the decline is mineral masking of the catalyst, because 1) experts tell us so, and 2) a vinegar bath definitely perks up a sad cat.
(The other major reason I've heard is that the substrate gets a wash coat of very high surface area aluminum oxide, and the catalyst is then deposited on the wash coat. If the wash coat overheats, it softens and loses surface area.)
....so to what extent will drier wood actually lower the mineral content of the air that hits then cat? (And is burning wood actually putting out water vapor AND aeresolized water? It seems like it should be.)
Obviously less water vapor equals less airborne minerals, but minerals must get airborne as flying ash and such too.
It also seems obvious that drier wood will, all other things being equal , mean higher firebox temps, which means more water vapor and less aeresolized water.
How much cat mineral depositation is a result of aeresolized water being evaporated, and how much is a result of smoke and ash passing through?
stoveliker
Minister of Fire
Good questions, and hard to answer.
1. I'm not sure that water is the main vehicle for mineral movement. Smoke (i.e. nanoparticles containing organic molecules - and more) likely contains much too. I would not be surprised if that carrier contains more minerals, as I think there is not much steam (small droplets of water) - it'll almost all be water vapor: given the relative humidity in the firebox the stability of steam will be negligible.
2. Catalyst poisoning is quite often related to compounds containing sulphur (and similar elements). Sulphur is a common "linker" of organic compounds to precious metal atoms (i.e. the active part of catalysts).
3. I am not convinced the acid bath removes minerals. After they have been there, at high T, a mild acid as vinegar won't really do much to minerals I think. See #2 for a possible reason why this works.
I do note that I am fairly knowledgeable in this area but would submit to people that actually have data, rather than the (well-informed) speculation above...
1. I'm not sure that water is the main vehicle for mineral movement. Smoke (i.e. nanoparticles containing organic molecules - and more) likely contains much too. I would not be surprised if that carrier contains more minerals, as I think there is not much steam (small droplets of water) - it'll almost all be water vapor: given the relative humidity in the firebox the stability of steam will be negligible.
2. Catalyst poisoning is quite often related to compounds containing sulphur (and similar elements). Sulphur is a common "linker" of organic compounds to precious metal atoms (i.e. the active part of catalysts).
3. I am not convinced the acid bath removes minerals. After they have been there, at high T, a mild acid as vinegar won't really do much to minerals I think. See #2 for a possible reason why this works.
I do note that I am fairly knowledgeable in this area but would submit to people that actually have data, rather than the (well-informed) speculation above...
Dustin
Minister of Fire
Me put wood in blazeking
house warm
Buy blazeking.
I’m helping.
house warm
Buy blazeking.
I’m helping.
I'd agree in that mineral transfer is probably not only by water aerosols, but in solid form (smoke) as well.
Besides that, all catalysts everywhere age and lose effectiveness. Mostly because the active surface declines. That can (as you mentioned) happen from deposits, but also because the finely dispersed noble metal atoms on the surface tend to accumulate into larger clusters by itself. Heat speeds that process up.
So even industrial catalysts (for chemical reactions in tanks, for instance) do not last forever and need replacement now and again.
In general surface dynamics are not fully understood, even today. So a lot of catalyst work is purely empiric.
There's a saying: God made the bulk of a material, but the surface is the devil's work. And that actually makes sense.
Besides that, all catalysts everywhere age and lose effectiveness. Mostly because the active surface declines. That can (as you mentioned) happen from deposits, but also because the finely dispersed noble metal atoms on the surface tend to accumulate into larger clusters by itself. Heat speeds that process up.
So even industrial catalysts (for chemical reactions in tanks, for instance) do not last forever and need replacement now and again.
In general surface dynamics are not fully understood, even today. So a lot of catalyst work is purely empiric.
There's a saying: God made the bulk of a material, but the surface is the devil's work. And that actually makes sense.
stoveliker
Minister of Fire
yes, coagulation. I don't think though that the vinegar thing is atomizing the (Pd?) again. Is it increasing the surface area of the alumina? (But one still needs the precious metal to be distributed, even if the alumina surface area is larger...)
And, yes that quote is from Wolfgang Pauli! Was in my office for a while (surface physicist...)
stoveliker
Minister of Fire
Lol. Made my day.
I agree; this is why BK is worth the money. They thought about it, and it works. (It's only my particular brain that always wants to know the answer to "why" - unless my kids ask me why, why, why...)
I think you should sell this to @BKVP and get a marketing commission
It applies to almost any wood stove.Lol. Made my day.
I agree; this is why BK is worth the money. They thought about it, and it works. (It's only my particular brain that always wants to know the answer to "why" - unless my kids ask me why, why, why...)
I think you should sell this to @BKVP and get a marketing commission
