I know, I know -- your first thought is to ask WHY would you want to do that?
I'm putting my property up for sale because I can't afford to keep it. I will be a sort of snowbird, moving with the weather, living in a travel trailer. At some point, I may find a place to stay on private property for the growing season, if my luck is good.
While cleaning up this property, I am making biochar from fallen tree branches. I see no point in leaving it in the garden beds, as the majority (by far) of the people here are of the Roundup/chemical fertilizer persuasion, or they will pave the entire place.
Some fearmongers are quick to point out that biochar can spontaneously catch fire, and tell you to put it in airtight metal cans (and someone even said this was even possible when the biochar was WET *rolly eyes*). However, I found a reliable source who said this is only possible the first time that biochar is exposed oxygen after charring.
After charring, I would like to inoculate it with some of the usual beneficial materials, including finished compost. At this point it would contain live microbes. I would like to store it in some lidded, food-grade plastic 5-gallon buckets.
Now, the main questions: How much oxygen do microbes require? How long could I keep the buckets sealed? Would it be a good idea to open the buckets, remove the contents, and fluff it up to incorporate fresh air, and then replace and reseal them?
Alternative idea: Add just the mineral-type nutrients for travel, and buy a fresh package of microbes to mix in when/if I find a place to settle?
Storing live microbes for long term isn't the easiest thing to do, you would need to be able to inject moisture, some food source (minerals with a bit of molasses) and O2 and you would need to also keep molds from gaining a foot hold on your char.
On the other hand, charcoal (char) is easy to store as is, no worries of moisture, sticky food stuffs for the microbes and no minerals.
You can bag it, can it, jar it, as long as it doesn't get wet it won't grow molds, this (for me) would be the way to take char with me over a long haul trip or series of trips.
I really prefer your idea of make the char and if you have them, add the minerals.
If you don't already have the minerals, don't sweat it, just can the char and wait till you are ready to use it to charge it up.
That way you don't have to keep track of anything, the char will be waiting for you to open the lid(s) and add the organisms and minerals.
Do you think that mold would be likely with just damp biochar? I grind mine down with water in a kitchen blender, so it is usually damp. And... would the mold really be much of an issue, or just kind of be a form of "self-starting organisms"?
Sealed buckets would be a concern for me. The microbes will quickly use up the oxygen and once that happens you'll either see a mass extinction of them, or the growth of anaerobic stinky microbes. Or both.
Do a test. Close up a container of activated biochar in an air tight container and wait for a week. Open it up and smell it. Does it smell healthy?
Many microbes go into a state of dormancy when there isn't adequate food or moisture. When you feed them and rehydrate them, they quickly come "back to life" and become active again. But lets assume the worst—that all of the biochar microbes all died. Reactivating biochar is as easy as mixing it into fresh compost when you get to your new location, so it's not as if you can make some sort of irreversible mistake that can never be corrected.
"The rule of no realm is mine. But all worthy things that are in peril as the world now stands, these are my care. And for my part, I shall not wholly fail in my task if anything that passes through this night can still grow fairer or bear fruit and flower again in days to come. For I too am a steward. Did you not know?" Gandolf
hau Sue, mold is a very real problem and something to be careful around.
Most of the time the molds are in spore form, we breathe them in with every breath but when these mold spores find moisture and some sort of food source they bloom and multiply rapidly.
When we breathe in active molds, our lungs suffer and serious consequences can arise (there have been deaths contributed to active molds being inhaled).
I prefer to store everything I can in a very dry state.
I would dry and store my char, knowing that when I arrived where I wanted to use it all I had to do is add it to some fresh compost to populate it with microorganisms.
While the idea of something wet catching fire may sound odd, it is quite common. Wet cotton is the biggest producer of spontaneous combustion in the transport business, and many chemicals when they contact water, will produce flammable gases, such as hydrogen and acetylene. The exothermic reaction is more than hot enough itself, to be an ignition source for those flammable gases.
As for the biochar. I made 5 gallons of powdered/chipped charcoal in the blender, and added 5 gallons of urine over several days, which it has absorbed. I'm guessing to keep it moist, adding another gallon or so a week until I need it? I produce 2-3 gallons a day, so it's not an issue, at least for me.
A way to conserve many of the microbes introduced during composting or other inoculation process would be to slowly dry the biochar in the shadow. Microbes will notice the reducing moisture and start producing spores or other resistant forms. Not all of them will survive, but some will. I once used old stored inoculated biochar and the response was amazing.