What is Charcoal?  How is it Made?

What is Charcoal? How is it Made?

When wood or other organic material is converted into charcoal, it undergoes pyrolysis, a controlled carbonization process that occurs in the absence of oxygen. During this transformation, volatile compounds—such as water vapor, methanol, and acetic acid—are driven off.  What you are left with is carbon.  Here's how it works:

The process of pyrolysis begins by superheating wood or organic materials in an environment without oxygen.  The heat can come from the organic material itself (Internal Heating), or it can be heated from the outside (External Heating).  Concrete or brick kilns are commonly used for charcoal made using an internal heat source.  The kiln is filled with wood, a fire is lit, and then the kiln is closed to create an oxygen free environment.  For processes using external heat, there is a fully enclosed chamber heated from the outside until the organic material begins to release enough energy to sustain combustion.  

As wood is heated, it spontaneously breaks down.  The breakdown products include:
  • Charcoal (carbon)
  • Water vapor
  • Methanol
  • Acetic acid
  • More complex chemicals (chiefly tars and non-condensible gases)
In modern production processes, gas and vapors from combustion are burned and recirculated for efficiency.

Natural Lump Charcoal

For natural lump charcoal, this is effectively the whole process.  For our Oak Large Lump Charcoal, the final step is to screen the charcoal so that only pieces between 2"-6" make it into the bag.  We save the rest for our High Desert Blend Briquettes.  For the briquettes and for our Thai-Style Charcoal, which is made from Rambutan orchard scrap that has been carbonized, there are a few more steps. 


Thai-Style Charcoal

First, the charcoal is ground to a uniform size and screened again.  It is then mixed with a slurry of starch and water so that it is a charcoal paste.  
For Thai-Style Charcoal, that paste is pushed through a mold at extremely high pressure, about 14,000 lbs per square inch. It comes out a super dense log, that is cut to length, and dried in a drying kiln to remove that moisture that was added in the slurry. 
This process creates an incredibly uniform charcoal with reliable and consistent characteristics.

Why Make Charcoal?

Lower Smoke Emission - Volatile compounds in wood contribute to smoke production during combustion.  By removing these compounds, charcoal produces significantly less smoke.  This is especially beneficial for grilling, where excessive smoke can negatively impact flavor.
Reduced Ash Content - Charcoal contains minimal impurities compared to raw wood.  As a result, it leaves behind less ash when burned.
Predictable Burn Time & Heat - Charcoal's uniform composition allows for more consistent heat output.  Unlike irregularly shaped wood logs with unpredictable moisture content, charcoal provides reliable temperature.

Back to blog

Leave a comment