Biochar
Biochar (def’n): A solid material obtained from thermochemical conversion of biomass in an oxygen-limited environment. Biochar can be used for a range of applications as an agent for soil improvement, improved resource use efficiency, remediation and/or protection against particular environmental pollution and as an avenue for greenhouse gas (GHG) mitigation. In addition, to be recognized as biochar, the material has to pass a number of material property definitions that relate both to its value (e.g., H/Corg ratios relate to the degree of charring and therefore mineralization in soil) and its safety (e.g., heavy metal content). Adapted from: Lehmann, J., and Joseph, S. (2015). Biochar for Environmental Management: An Introduction. In: Biochar for Environmental Management – Science and Technology, 2nd edition. J. Lehmann and S. Joseph (eds.). Routledge.
Once a marginal and often costly by-product, biomass waste can be viewed as a valuable resource. In creating biochar, biomass becomes a sustainable and value-added product for urban and rural agriculture and forest communities: creating jobs, improving soil (and thereby reducing greenhouse gases) and reducing forest fire hazards. Biochar gives value to dead trees and biomass waste while reducing carbon dioxide in the atmosphere. Biochar is a fine-grained charcoal made by pyrolysis – the process of heating wood with limited to no oxygen in a specially designed furnace.
Biochar can be a single product or a co-product of a biorefinery operation.
Additional Resources
International Biochar Initiative