Kingsford Factory Tour: How Charcoal Is Made Slideshow

The first step to making charcoal is gathering a mountain of wood scrap called "hog fuel." 

The operation begins when the wood scrap is placed on conveyor belts that carry the wood into a wood hog, which grinds the hog fuel.

After the ground-up hog fuel comes through the wood hog, it is formed into a uniform particle size and then pulverized to sawdust. "The more uniform the particle size the more consistent the process is," said plant manager Steve Miller.

Since wood is typically 50 percent moisture, it is necessary to bring to that moisture to around 5 percent. To achieve this, the sawdust is sent into a large spinning drum, which resembles and works much like a clothes dryer. The sawdust remains in the drum for half an hour. Two of the three dryers at the Kingsford factory in Belle, Mo., are from the original plant in Kingsford, Mich.

Next, the dried sawdust arrives at the furnace, a five-story roaster, where it transitions through each level, some at temperatures higher than 1,000 degrees. At this point, gases are driven off, leaving wood carbon.

By sucking out the oxygen from the sawdust, gases are evacuated so that the sawdust is baked, not burned. The After Combustion Chamber uses recycled heat that not only heats the dryer, but also runs the briquette dryers and the incinerator.

The black sawdust known as wood carbon char then goes to a blue silo. 

Next door to the blue silo, a worker mixes the char with coal, limestone, and cooked corn starch (which acts as a glue and binder). Then, the mixture is sent to the rotary presses. At first, the pressed briquette is soft, like a brownie, because of the cooked corn starch.

The brownie-like briquettes are dried for two hours to keep the char percentage high before emerging as the harder briquette bought in stores. 

Once fully dried, the briquettes are bagged on conveyors and later "palletized" for shipping.