Circular valorization of crop and wood residues through pyrolysis for biochar

The PA presents an integrated pyrolysis facility that converts agricultural crop residues and wood waste into biochar and wood vinegar through a retort-type dry distillation process conducted under oxygen-limited conditions. The technology is based on a modernized interpretation of traditional charcoal production, adapted to meet current environmental and quality standards.
The pyrolysis process enables the controlled thermal decomposition of biomass while separating and capturing both solid and liquid fractions. The solid fraction consists of biochar, produced in granular and powder forms, characterized by high carbon content, porosity, and long-term stability. The liquid fraction, obtained through condensation of pyrolysis vapors, is wood vinegar (bio-pyrolytic distillate). Non-condensable gases (syngas) generated during the process are recovered and reused on-site to sustain the thermal energy demand of the reactor, ensuring operational energy self-sufficiency and low emissions.
Biochar functions as a multifunctional soil amendment, improving soil structure, aeration, water-holding capacity, and nutrient retention, while providing a stable habitat for beneficial microorganisms. Wood vinegar, with an acidic pH of approximately 3.6, contains over 200 organic compounds—including pyroligneous, humic, and acetic acids—and is applied via fertigation, foliar spraying, or soil treatment. It acts as a natural biostimulant, soil disinfectant, and biocontrol agent.
A key innovation of the system is the combined application of biochar (alkaline, pH ~8.7) and wood vinegar, enabling soil pH balancing and enhanced microbial activity. This synergistic use improves nutrient availability, supports soil regeneration, and reduces reliance on synthetic inputs.