Bio char

[r.man]

Put power to a small continuous run bio char maker last week that was built by people educated at the University of Iowa. It is built into a large shipping container and is being put through its paces by one of its designers/builders while training its new operator. I saw it lit and approaching its processing temperature but had to leave before it started producing. I will get some production numbers from it after they have run it for a few shifts.

[Compensation]

Basically a charcoal oven right? If so I think you beat me too it. I was going to ask if anyone makes their own charcoal. I want to attempt it with my incinerator since its easy to close up. Maybe even bust it down and make briquettes.

[r.man]

Not a charcoal oven, more of a sawdust baking machine. Biochar is generally a powder so you don't use lumps of bio mass since you want the material to break up into small particles during the process. I also am not sure of the composition of biochar compared to charcoal. I think that the difference is that the bio is formed using different temperatures to get a slightly different chemical composition but I am not sure. I do know that with this machine you keep filling a hopper with sawdust at one end and biochar keeps coming out of the other end. Not sure of the production rate yet but with a continuous supply of sawdust the process should product X number of lbs of biochar per hour for as long as you want to operate the machine. Takes a few hours to get up to operating temps so the ideal would be to run long shifts or a 24 hour operation.

[Compensation]

Ohh OK, I just done a quick search last night and it said its baked for specific needs and showed a pic of chared wood. What will you use it for? Any pictures?

[OneWithWood]

I will be curious to see how it goes also.  Bio char is a great soil additive and if someone comes up with an economical way to turn sawdust into bio char they may very well have something. 

[r.man]

I will not do anything with it because the machine is not mine, I was paid to put power to it. The customer will be producing biochar to both sell and use on their own property. 

[Compensation]

Looks like i got too excited when i read it and started punching buttons. Well i was told that whoever hooks up power to a bio char oven gets free bio char for a week. Might want to run that by them  :D

Any chance of pictures?

[r.man]

I prefer to get paid money to hook things up although I would consider a delicious chicken. Not sure what I would do with a weeks worth of biochar. My week or their week? I will take some general pictures but the best part, the reactor itself, is proprietary and the designers have specifically asked that no tech details or pictures be circulated. ( one picture is worth a thousand words )

[Stroover]

Biochar? Huh...what a great idea! I don't think anybody does that here, and our province is looking for ideas to make work for our people so they don't move out west... Hmm.... I've gotta look into this!

[red]

Obviously this idea of making Biochar from sawdust has been around for a while . . just wondering if anyone is doing it ? 

[peakbagger]

There is supposedly a firm bringing in German technology to make BioChar at the former East Millnocket Maine papermil that has been vacant and partially torn down for years. There was a prior firm that was also proposing to make torrefied pellets for fueling pellet boilers, they could not get financing. Lots of firms have tried but no one seems to come up with a good enough business model. 

[bluthum]

For the prices I see for packaged biochar it seems hard to see how it would be difficult to make profitably. But it must be so.

[peakbagger]

I used to work on biomass boilers for power plants. If the configuration of the boiler is not great unburnt fuel can get carried through the downsteam heat transfer area. It would get separated out in a couple of places and removed from the boiler. The unburnt fuel is called char. Sometimes its flakes sometimes it looks like rice. Normally its reinjected to the boiler to reburn. At one particular plant it had a very poor grate design and produced lots of char. They collected it off to the side in separate silo and then reintroduced it. The reinjection was problematical but it turns out that they had lots of customers for the char, the trucks were lined up to haul it off. 

With just a bit of tweaking, a biomass boiler could be converted to burn off the volatiles in the wood leaving effective chat to be hauled off as bottom ash. It would still produce power but less so it would be commercial decision on which way the split made the best payback. No doubt if there is carbon tax and value for sequestering carbon that char production will take off. 

[Don P]

Can you tweak such that you can burn the volatiles and get reasonable fuel from that fraction and leave the majority char.

[Dan_Shade]

I've made some small scale in a sealed paint can with a few holes punched in the top.

I tossed it into a fire and let it all burn out. 

[peakbagger]

Can you tweak such that you can burn the volatiles and get reasonable fuel from that fraction and leave the majority char.

I think yes, its a variation of gasifier technology. 

[Joe Hillmann]

With just a bit of tweaking, a biomass boiler could be converted to burn off the volatiles in the wood leaving effective chat to be hauled off as bottom ash. It would still produce power but less so it would be commercial decision on which way the split made the best payback. No doubt if there is carbon tax and value for sequestering carbon that char production will take off.

That is kind of how I cook syrup.  I get a much faster boil if I keep adding fresh wood, but charcoal builds up and doesnt burn fast enough to allow me to keep a good boil so every so often I shovel charcoal out the back so I can put more wood in the front.
I throw the charcoal in a barrel of water then dump a few barrels of it where the new compost pile will be for the year.  My hope is the charcoal holds on to any nutrients that would otherwise leak out of the pile.  After a few years of rotting the pile, charcoal and all, gets spread on the garden.

[Southside]

Our farming practices are centered around soil health so I do like the benefits of bio char.  I find it ironic that in order to mass produce it commercial systems would have to be designed to be less efficient resulting in the need for more timber to be consumed at a time when there are now carbon exchange programs that pay timber owners not to harvest their timber.  

[Don P]

My mind is wondering if this can produce power and biochar in an overall negative carbon footprint mode?

[Southside]

The laws of energy and physics tell me no. The input will still have to be harvested and transported. 

Nothing is free. Good, but not free.

[brianJ]

That is kind of how I cook syrup.  I get a much faster boil if I keep adding fresh wood, but charcoal builds up and doesnt burn fast enough to allow me to keep a good boil so every so often I shovel charcoal out the back so I can put more wood in the front.
I throw the charcoal in a barrel of water then dump a few barrels of it where the new compost pile will be for the year.  My hope is the charcoal holds on to any nutrients that would otherwise leak out of the pile.  After a few years of rotting the pile, charcoal and all, gets spread on the garden.

That is a great system

[Joe Hillmann]

I have also thought that if a person heats with wood and has a use for charcoal a stove with two chambers sharing one chimney could be used to provide heat and charcoal.

My idea is each chamber would be able to be sealed to be almost air tight.  A fire would be lit in one, and once it is down to coals it would be closed up so air can't get in but some air can still get out through the chimney and the fire gets choked out.  The next day while that one is cooling down the second chamber is used the same way.  On the third day the first chamber is emptied of its coal and the chamber is refilled with fresh wood.

I think this method would work with an outdoor boiler surrounded with a water jacket or a Russian masonry heater.  Because in both you can burn a hot fire and store the heat for later.  With an outdoor boiler you wouldn't have the mess of the charcoal in the house.

The charcoal could be used for carbon sequestering, bio char,blacksmithing, or to run an engine with a gasifier.  Or you could inject high temp(at atmospheric pressure) steam into the charcoal to create activated charcoal for filtering.

I don't know if such a system would be carbon negative but if you have a use for the charcoal and want the heat it could be a worthwhile system.  Most methods of making charcoal don't utilize the heat which makes this method at least a bit more environmentally friendly.

[hickernut]

I've not made any Biochar however, this is a really good video on the process and design for a small scale retort. 

https://youtu.be/svNg5w7WY0k

Now that I have a sawmill I've been saving all the clean scraps for biomass and hopefully will be making some Biochar this winter. 

[Don P]

I followed that and watched the episode showing his full scale setup, quite impressive. He is using the heat from the process t run a dry kiln and greenhouse.