Pyrolysis and Biochar explained in simple terms

For someone new to biochar, some of the terms used can be confusing. Understanding what biochar and pyrolysis mean can give you a better understanding of the processes used to create biochar, as well as a better understanding of how you can benefit from it.

Biochar is essentially a form of charcoal that can be used for a whole range of different purposes including soil amendment and conditioning. It is formed from biomass (which is just organic matter) from a process called pyrolysis (which is explained below). The word “biochar” comes from an amalgamation of “biomass” and “charcoal” and has been in use since the 20th century. The origins of biochar date back to pre-Columbian Amazonians that were believed to have used it to improve soil productivity. They produced it by covering hot agricultural waste in pits and trenches, to reach the low oxygen levels required to form biochar. Biochar can come in many different forms, such as raw, in pellets, mixed with fertiliser and mixed with water or other liquids to form a slurry. This enables biochar to be used in a variety of different applications.

Pyrolysis is the term used for the process of creating biochar. Pyrolysis is the decomposition of materials at very high temperatures, resulting in a product that can-not be converted back into its original state. It also requires very low oxygen levels to be present, and therefore needs to happen in a vacuum or tightly controlled conditions. The word itself comes from Greek origins of “pyro” – meaning fire and “lysis” – meaning separating. The process of pyrolysis is not only used for the creation of biochar, but also for many products produced in the chemical industry. Pyrolysis of biochar can occur at two speeds – slow or fast. Both have their advantages, as fast pyrolysis can occur within minutes but produce little yields of biochar, whereas slow pyrolysis can create larger yields of biochar with less by-product but take hours to produce. The process of pyrolysis has also been around for thousands of years. As mentioned earlier the Amazonians used an early form of pyrolysis to create biochar, and the ancient Egyptians also used pyrolysis to create methanol, which they then used to embalm their mummies. Modern technology however, has made it easier for the removal of oxygen, resulting in not only higher quality biochar, but the elimination of toxic gases such as CO2 being released in the process.


Now that you understand what biochar and pyrolysis are in simple terms, you may find that it helps you to understand the benefits that biochar can bring to your crops, soils and livestock.