Possible uses and applications of biochar and charcoal produced by slow pyrolysis kiln prototype

Wood residues from forestry represent an interesting source for economic valorization within a circular economy framework offering forest owners a significant opportunity for product diversification. From this perspective, wood charcoal offers an exciting prospect. To develop this prospect, new mobile kilns were tested on site, evaluating both the process and the final products.

This new type of kiln features a mobile metal structure and can operate on the field. It has a loading compartment for the biomass to be carbonized, an automatic wood chip burner, and a rear chimney. As part of this research, the pyrolysis process was standardized and operated at two different operating temperature (400 and 500 °C).

These innovative kilns can produce traditional charcoal or biochar, which can in turn generate activated carbon through physical processes. Charcoal has undeniable positive qualities and is highly versatile: energy use, treatment of industrial wastewater, water purification, and air filtration; in the food industry for the bleaching and deodorization of wine, vinegar, fruit juices, and other food products; in the herbal, pharmaceutical, and cosmetic industries; and in the textile and agricultural sectors as a soil conditioner, known as "biochar." Forestry or agroforestry biochar of woody origins is a new product with very interesting application prospects. Charcoal produced in forestry supply chains could also benefit from PEFC Chain of Custody certification, reaching a more qualified market while adhering to the core principles of the Circular Economy and the Green Economy.

This research led to the characterization of 5 different charcoal matrices, evaluated against technical standards based on their application prospects. In addition, two process standards were proposed to evaluate their influence on the main characteristics.

The activities carried out were supported by the EU-Potarch (COST Action CA22155 European Unionion2019s Framework Programme for Research & Innovation).