How to crunch the biochar bits even more

I have been using the two panels of plywood method to crunch the biochar.  When done with cooking, I simply put it between the two panels and drive over it when parking. I have recently found a way to make it even more effective.

After I have driven over it many times, it starts to crunch less.  Of course, I have my own designated rake and dustpan, exclusively for biochar :).  When it hardly crunches anymore, I open up the panels, and pick up the really small stuff. Then I spread out the remaining bigger ones, close the two panels again and start to inoculate the small ones.  You get a really huge crunch again!  This lasts for awhile and then when that crunch quiets down, I add the second part to the inoculation.  I didn't realize how much more crunching there would be after it quieted down the first time. Anyway, I end up with smaller bits, which should expose more surface area and be more efficient biochar.
John S
PDX OR

Hi John, my mum used to make biochar and used the neighbours tractor and yard to do it. She's fire up a big kiln of char, then drive back and forth until it was pretty well crushed and then sweep it up for sale.

Thanks Feidhlim,
I love how everyone is adapting the methods we are sharing to their particular situation.  Using a tractor is a great idea.  I live in a suburb, so I don't have a tractor, but I think it's great that everyone who has access to one can think in these terms.
John S
PDX OR

Cool method. I need to put mine into a wood sandwich too. I just run it over in place a few times with my truck. I am sure I lose a TON of efficiency that way.

Come to think of it, if you have a dirt or gravel driveway, the plywood method would be even more useful.  You'd probably just grind the biochar into dirt or gravel and get back only a small portion of it.  My driveway is cement, but I still think I lose less with the plywood panels. We get a lot of rain in certain parts of the year and it's dry and dusty in others.  One could lose a lot either way, and there is the negative health impact of breathing in the dust.  No dust with the panels, either, for me.

John S
PDX OR

For me I don’t even bother crunching the char up. I tend to need it course for my aquaculture filters so no need to. But here is how it does slowly get crushed. When it comes out of the fire it gets immediately dunked in water. That seems to help break it some more. The char then gets strained from the water and placed in a container to dry. Once sufficiently dried it gets sifted to remove the fines from the course stuff as I want to put the fines in compost or for my ducks but I do not want it causing issues on my fish farm. If I notice any big pieces I break them up a bit. The char then gets dumped into a storage container until needed. Each time it gets transferred it gets broken up a bit more. Then I put the char in one of my filters,  rinse it to Remove any fines and good to go. After a week or two the char filter is plugged with bacteria and fish manure fines, I take it out to my garden and dump it there. Now this tends to take place in winter so it is freezing outside and the char is water logged. In the spring when things have thawed the frozen char just crumbles nicely. So while there is a little labour involved I think it is a simple method for crushing. Pieces that get missed tend to get crushed over time in the garden like being stepped on, weeding with a hoe, rototilling, etc.

Steven McKraken wrote:Now this tends to take place in winter so it is freezing outside and the char is water logged. In the spring when things have thawed the frozen char just crumbles nicely.  

Interesting. Most of my char is made during the winter. I don't have an aquaculture setup, but I could certainly soak it in water and then transfer it outside. I bet even just sitting in a bucket outside would give it enough freeze/thaw cycles to break it down.

I'll have to try that!