Charcoal has many uses beyond cooking, and it’s easy to make. It is a precursor for “activated” charcoal, which we’ll discuss in the next episode of Survival Tips. (Activated charcoal aka activated carbon simply has a much greater surface area, which makes it more reactive). You can use powdered charcoal whenever activated carbon is called for, but it will be much less effective.
Knowing how to make it is a useful skill, and one that is easy to learn and practice. Basically, you just want to heat some wood in the absence of oxygen so it doesn’t burn. Heating drives off water and volatile compounds, leaving just carbon. The resulting briquettes can be left whole for cooking, or ground into a powder for filtration and poison treatment.
However, knowing how to make it is a useful self-reliance skill, and far less expensive.
Survival Tips S1 E4 — Making Charcoal (video goes live December 25th in the morning)
Charcoal Making Procedure
Watch the video for details; here’s an overview:
- Select a dense hardwood, if available. The more dense the wood, the more charcoal you’ll get for your effort.
- DON’T use pressure-treated lumber. It contains chemicals that make the charcoal useless for cooking, filtration, or ingestion.
- Cut or chop the wood into uniformly sized chips or blocks. If they’re all the same size, they’ll all “cook” at the same rate. Obviously, it’s difficult to make them uniform when using a hatchet or machete — just approximate and get on with the job. The larger the blocks, the longer it takes to make the charcoal.
- Heat the wood in the absence of oxygen. You can use a pot with a lid, for example. Drilling holes in the bottom of the pot helps get the heating process underway by igniting a few bottom block of wood. These will turn to ash and be useless for charcoal, but it does speed up the process for the rest of the wood in the pot. If you can’t drill or punch holes in the bottom of your container, no worries — it’ll just take longer.
- If you’re using a container with holes, place over a live fire and get the blocks burning with a flame, then cover loosely with the top. At first, the smoke will be white or light gray, and is mostly water vapor and volatile compounds. When the smoke turns dingy tan, place the lid tightly on the pot and keep the fire going.
- After a couple of hours or so, depending how much you’re preparing, the smoke output will drop. A this point you can set the pot right down in your fire and pile up the hot coals around the pot. It will help to cover the pot entirely with dirt and ashes, but it’s not mandatory. Then just leave the pot to cool for several more hours or overnight.
- If you have no pot, you can wrap the blocks in foil, and if you don’t have that, you can just ignite a pile of blocks, get them good and burning, and then cover them with dry sand or dirt, leaving a small vent at the top. After several hours, you’ll be able to pick around and get some charcoal.
When you check the pot, you might find some pieces that are still wood — you didn’t cook them long enough. Or you’ll find that they are covered in ash — you let them get too much air. The pieces you want will be black and very light, and will crumble easily in your hand.
If you undercooked it, it’s easy to start up the fire again for a second round. Cooking time varies widely depending on many factors, and the only way to get it right is to get a feel for it with plenty of practice.
Uses for Charcoal
- Cooking. Wood burns with a flame, but charcoal smolders, so it’s easier to keep the heat even.
- Filtration. Carbon (which is what charcoal is made of) filters a wide range of impurities in water, including especially chlorine and volatile organic compounds, which give water an unpleasant taste and odor. It does not remove minerals or salts. You can make a simple, fairly effective water filter with a sock, some dried grasses, and powdered charcoal.
- Poisoning. Activated carbon is the treatment of choice for many types of acute poisoning (not long term accumulation of toxins like herbicides). It binds with the poison to prevent absorption in the stomach or intestines, then passes. It should not be used when the poison is an acid, an alkali, or a petroleum product.
There are many more uses for charcoal; comment below!
In the next episode of Survival Tips we’ll see how to make activated carbon from your homemade charcoal, and we’ll consider some additional uses for it.