What would happen if we condensed wood smoke and collected it?

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tart

New Member
Jan 14, 2021
3
ontario
I know that this is kind of breaching the topic of gasification, but I was laying in bed the other day thinking about making a giant condenser on purpose to capture 100% of the wood smoke/gases and purposefully collect creosote.

My guess is it would make a thick tar, which perhaps could be repurposed and reburned at a later time all while reducing the carbon emissions by quite a lot.

Has this been explored outside of gasification where the smoke is filtered out and hydrogen is burned?
 
This is actually what new stoves are trying to achieve...though they skip the 'capture' and 'condense' steps. But they use clever design and additional components to burn the wood smoke before it ever goes up the flue - so the emissions are more along the lines of 'true' gasses... CO2, water vapor, some NOx, etc.

Once you get into an actual capture, condense, store, reburn later scenario, you can run into a lot of headaches pretty quick - and there is no real benefit. So best just to burn the smoke at the source and as-produced.
 
If you have ever used liquid smoke flavoring, its made from condensed wood smoke with any volatiles knocked out of it. Its a lot easier to burn it right once than try to collect it and burn it again. The industrial version is rapid pyrolysis where the volatiles like lignin and wood alcohols are released from the cellulose and then captured and then is turned into a liquid fuel. http://www.ensyn.com/heating-fuels.html
Two of the pictures is from a project I managed in North Conway NH and I bought one of the banners.
 
Your goal is actually the part that gasification struggles to avoid.

Getting the chunky gooey stuff out of the gas is the problem that has not yet been overcome in an affordable, low-maintenance way for small gasifiers.

Enthusiasts still build small gasifiers to fill bottles or run pickup trucks or generators, but you really have to be an enthusiast to put up with all the filtration problems on homemade gasification. (As a preview, one of the potential problems is hydrocarbon goo plugging the emergency pressure relief valves in your system. That's not really for the faint of heart.)

If you want to get as much heat as possible out of your wood (short of turning it into pellet fuel), burn it in a modern stove. Small gasifiers waste all the BTUs that you get from burning the cellulose (cellulose is good for 7k BTU/lb, which is less than the volatiles, but why waste it?).
 
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FYI, home gasifier dont burn creosote, they have internal knock out pots or filtration media to take out the gooey stuff. The gas they burn is mostly Carbon Monoxide (CO) with some other non condensable gases. The wood used has to be super dry or the water vapor along for the ride can really gum things up. A homebrewer has a good chance of getting a dose of CO as its odorous and colorless.
 
Wow! I wasn't expecting such good replies!

Your goal is actually the part that gasification struggles to avoid.

Getting the chunky gooey stuff out of the gas is the problem that has not yet been overcome in an affordable, low-maintenance way for small gasifiers.

I envisioned a similar system to a lab style condenser tube but just...really big/fat pipe running up then back down in a spiral where everything can be captured, but it would probably be very silly looking to say the least!


This is actually what new stoves are trying to achieve...though they skip the 'capture' and 'condense' steps. But they use clever design and additional components to burn the wood smoke before it ever goes up the flue - so the emissions are more along the lines of 'true' gasses... CO2, water vapor, some NOx, etc.

Once you get into an actual capture, condense, store, reburn later scenario, you can run into a lot of headaches pretty quick - and there is no real benefit. So best just to burn the smoke at the source and as-produced.

Yea, this is a great point. I wonder what is required to condense down those final gases into liquid form (not that its efficient or a good idea)


Take some melatonin before retiring
There's still a few minutes between laying down and falling sleep ;) Hahahahaha

@peakbagger Very cool photo's, my father and I have discussed at length about gasification to run generators during an emergency, and what is involved. I know they don't burn the creosote but instead the hydrogen gases and the like as you mentioned. There was a process a Canadian university was working on to convert those gases into a liquid biofuel that he kept going on about, I'm assuming that's very similar to the projects you may have overlooked
 
The technology has been around since prior to WW2. It just comes down to if someone wants to make one dollar worth of fossil fuel energy and willing to spend $3 to do it there is plenty of technology out there to do it. Let oil go up to $100 a barrel and then it makes sense. Since that is not happening anytime soon, the only way biofuels become economically attractive is to put in incentives to pay the difference or carbon taxes to drive the effective price of oil up.

I see better finances for converting polyethylene plastics to liquid fuel by hydrolysis instead of burying it in landfill but that is not "green".
 
This is actually what new stoves are trying to achieve...though they skip the 'capture' and 'condense' steps. But they use clever design and additional components to burn the wood smoke before it ever goes up the flue - so the emissions are more along the lines of 'true' gasses... CO2, water vapor, some NOx, etc.

Once you get into an actual capture, condense, store, reburn later scenario, you can run into a lot of headaches pretty quick - and there is no real benefit. So best just to burn the smoke at the source and as-produced.


Yea, this is a great point. I wonder what is required to condense down those final gases into liquid form (not that its efficient or a good idea)

You basically have compression and/or cooling if you want to get to liquid. Obviously, water is pretty easy, just cool below 100°C at atmospheric pressure. CO2 - believe you'd need to compress to about 900psi at 25°C "room temp" to get liquid. You can then trade colder/lower *pressure from there, or warmer/higher *pressure...until you run into some other phase change. NOx... guess you'd have to pick and choose, there...
 
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The technology has been around since prior to WW2. It just comes down to if someone wants to make one dollar worth of fossil fuel energy and willing to spend $3 to do it there is plenty of technology out there to do it. Let oil go up to $100 a barrel and then it makes sense. Since that is not happening anytime soon, the only way biofuels become economically attractive is to put in incentives to pay the difference or carbon taxes to drive the effective price of oil up.

I see better finances for converting polyethylene plastics to liquid fuel by hydrolysis instead of burying it in landfill but that is not "green".

You can go on YouTube right now and watch people fire and drive cargo trucks that were retrofitted to run on woodgas in WWII. Also enthusiasts who are running their pickups on it today!

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I have a buddy whose dad rigged a truck to run off wood gas. I'll try and snap a pic of it tomorrow. The guy is a literal genius. He also devised some way to create and store power off of a wood burner. It's not a lot but it will make enough to power his essentials through the night. All that and the guy owns/works at a glass shop in town. He's a hell of a mechanic too.
 
I know that this is kind of breaching the topic of gasification, but I was laying in bed the other day thinking about making a giant condenser on purpose to capture 100% of the wood smoke/gases and purposefully collect creosote.

My guess is it would make a thick tar, which perhaps could be repurposed and reburned at a later time all while reducing the carbon emissions by quite a lot.

Has this been explored outside of gasification where the smoke is filtered out and hydrogen is burned?
What about condensing the creosote onto porous ceramic pieces which can then be burned and recycled. I don’t have a mechanism for this, it’s just a blue sky idea.
 
I have a buddy whose dad rigged a truck to run off wood gas. I'll try and snap a pic of it tomorrow. The guy is a literal genius. He also devised some way to create and store power off of a wood burner. It's not a lot but it will make enough to power his essentials through the night. All that and the guy owns/works at a glass shop in town. He's a hell of a mechanic too.
I thought it's interesting that at the end of WW2 there were over 750,000 wood gas vehicles worldwide. Some came off the auto assembly lines with a wood fuel option. Instead of gas stations some areas would have "wood stations" with locals supplying motorists fuel.
 
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What about condensing the creosote onto porous ceramic pieces which can then be burned and recycled. I don’t have a mechanism for this, it’s just a blue sky idea.

Also called a badly maintained un-lined chimney - well, without the re-use...
 
1. Use a heat pump to chill chimney liner and condense creosote.
2. Install auto-sweeper to knock down all the gunk periodically and re-burn it
3. ????
4. Profit
 
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1. Use a heat pump to chill chimney liner and condense creosote.
2. Install auto-sweeper to knock down all the gunk periodically and re-burn it
3. ????
4. Profit
What I was thinking, a chamber with inert "rock" pieces of high surface area, cooled preferably with a heat exchanger that reclaims the heat. The heat pump is a good idea because then the collection chamber could be outdoors. Change out rocks when chimney is swept. Auto-sweeper sounds like fun also.
 
What I was thinking, a chamber with inert "rock" pieces of high surface area, cooled preferably with a heat exchanger that reclaims the heat. The heat pump is a good idea because then the collection chamber could be outdoors. Change out rocks when chimney is swept. Auto-sweeper sounds like fun also.
The problem with all these ideas, as I see it anyway, is that you'll have a hard time creating enough surface area to collect everything, and if you do have enough surface area it will get clogged up almost immediately.
 
I mean, it's not that hard, look at alcohol distillers, could probably just coil a chimney pipe up and around then have a brush that auto scrubs once a day/week/whatever
 
I mean, it's not that hard, look at alcohol distillers, could probably just coil a chimney pipe up and around then have a brush that auto scrubs once a day/week/whatever
But alcohol is a liquid