Transcription
Have you ever wanted to know what biochar is, and then you've attempted to look it up or had somebody try to explain it to you in very scientific terms, and your eyes just gloss over? I'm going to explain to you in layman's terms what it is, how it's made, and the things that it can be used for. Stick around.
So, what is biochar? It's just charcoal. It's charcoal that's been created from biomass through the process of pyrolysis. Biomass is nothing more than living or recently living organic material. In the case of making biochar, quite commonly what is used is wood, but many different substances that were once living could easily be made into char. There are a number of different thermochemical conversion processes used in making biochar. However, the vast majority utilizing wood as a biomass is made with the process of pyrolysis.
So, what's happening when we make biochar? This material undergoes a form of thermal decomposition. It's decomposing due to the heat that's being applied, and that process is called pyrolysis. I'm going to explain now the difference between pyrolysis and combustion, and what makes this different from what you get out of your wood stove or your fireplace. Organic material undergoing the process of pyrolysis, and you'll be left with this. Organic material undergoing the process of combustion, and you'll be left with this. What's the difference? The difference between these two is that this has undergone that thermal decomposition in the absence of oxygen.
So, in order for a fire to occur, you need three things. It's called the fire triangle. You've got heat, you've got fuel, and then you've got oxygen. If you remove any one of those three things of the triangle, a fire cannot occur. This needs that third element, and it doesn't have that. It's got the heat, the fuel exists, but there's no oxygen. So, this can no longer burn. And what you're left with is you're left with a very, very pure form of carbon. Now, there are going to be some residual oil and some residual tars and things like that, but essentially, this is very, very pure.
So, what's happened in this instance is that this has been heated to its ignition temperature. When it reaches that ignition temperature, it starts to off-gas and it starts to drive off all of the volatile gases that are flammable. I've experimented with and had some limited success with some of the different processes that are out there where you build a pile, burn it from the top down, and before it turns to ash, you want to go ahead and quench it and then extract your charcoal from there. I've experimented with the cone pit. I've experimented with the trench method. However, the system that I've currently had a lot of success with and I've settled on is the biochar retort. If learning more about that system interests you, I'll put a link in the description directing you to some of the videos I've made on how that system was designed and how it operates.
The thing I like about the system that I'm currently using is it's very hands-off. I can essentially light the system, come back the next day, and I've got high-quality char, and I've had very limited interaction with it from the point at which I light it to the point where I go ahead and collect it. I do not have any experience using a kiln, but I thought I would mention it in the context of this video as another option of a closed system that is used quite commonly for pyrolysizing wood for biochar.
I think it's important to note that biochar got its start more than 2,500 years ago in the Amazon basin. The indigenous people in that area at the time had discovered this dark, rich, fertile soil that had nutrient and water-retentive qualities, highly sought after for growing plant matter. It's called Terra Preta, or black earth in Portuguese. And aside from its moisture-retentive and soil-building qualities, it has a lot of other specific uses, and I'd like to go ahead and highlight those now.
One of the very unique things about biochar is just it has an incredible amount of porosity. The surface area of one gram of well-made biochar is said to be equivalent to a half of an acre, or 2,000 square meters.
One of its uses is to remediate both soil and water. Biochar is negatively charged, so it's going to attract positively charged chemicals and or nutrients. It's going to draw those elements into the char, and it'll be retained. I think that's pretty cool about biochar is just that it's environmentally friendly. This piece of char could potentially be around for thousands of more years. It's a really effective way to take a waste stream, something that would ordinarily either go into a landfill or just naturally decompose into the atmosphere, and sequester it in a way that it does something beneficial by putting back into the Earth.
Before inoculation, char in this form needs to be crushed, and ideally, it needs to be crushed down to a quarter inch in diameter or smaller. Crushing is another important step, but it takes time, and I generally do it in kind of more of a passive way where I will either crush it in the wheelbarrow or I will put this in a feed sack and then walk on top of the feed sack. I've created a video detailing that process. I'll put a link as well into the description.
One thing that's very important that you do before you add this to your soil as an amendment is that you pre-load it, or you inoculate it. It's very important that you do that because again, this is a blank slate. This is very, very absorbent with all that pore space, and what it's going to do is it's going to have a negative effect. If you take something like this and put this directly into the soil, it's going to actually draw nutrients away from the plants who are competing for those nutrients.
Here's a list of some of the items that may be used to inoculate your char. It's not as important on which of these items that you choose, but it's important that you choose one of them. Essentially, what you're doing is you're filling up that pore space with something so that that pore space isn't going to be thirsty for the nutrient and competing against the plants that you're trying to grow.
A natural byproduct of this process is when this cools, tar and resin will solidify on its surface, essentially making it hydrophobic, meaning that it will not absorb water. So, it's very important to try to get that hydrophobic property lessened or completely eliminated by introducing it to water. I typically don't worry too much about that issue because it's going to remain in this compost yard. This char that I've crushed is going to wind up being in the chicken yard, and it's going to have plenty of time for all of those resins and oils and tars to break down, and then the inoculation process is going to take place. It's going to be in that compost absorbing nutrient from the compost that's been generated in that yard for at least two months.
The two primary ways that I inoculate my char is put it directly into the compost piles, or I'll utilize it as livestock bedding within my chicken coops. Utilizing the char in the bedding areas of my chicken coop has a couple of different benefits. It's going to absorb the nutrient from their manure, but it's also going to absorb and reduce the amount of odor that comes from that manure. They seem to like it quite a bit.
If you're interested in learning more about biochar, click now to enter my video playlist.