Mobile biochar production by flame carbonization: Reducing wildfire risk and improving forest resilience
Forests today face a myriad of threats stemming from insect and disease infestations, drought, overstocked stands, wildfire risk, and large volumes of woody residues created during forest restoration activities. In 2022, The USDA Forest Service started an initiative aimed at reducing stand volume and hazardous fuels. This effort has been productive, but leads to the accumulation of waste biomass, such as slash, which has low market value and poses challenges for safe disposal.
Biochar production provides a relatively safe and climate smart opportunity to reduce this waste biomass, while simultaneously generating a climate smart and economically viable product. On-site biochar production methods provide a way to reduce the volume of forest slash and wildfire risk.
Three classifications of on-site biochar production methods are examined in a recent General Technical Report:
- Conservation burn-piles: Specially constructed burn piles that reduce airflow and soil impacts while also optimizing biochar production.
- Flame-cap kilns: Simple kiln containers used to manage combustion rates and preserve char.
- Air curtain burners: Insulated fireboxes with active countercurrent air flow for better process control and emission reduction.
These production technologies offer managers an array of options for biochar production to suit projects of varying scales, fire safety, air quality constraints, and financial investment.
In general, biochar is used on-site or near-site to improve soil properties and processes. Biochar is a unique and widely valuable material. The abundant and reactive pore space of biochar can be leveraged to help improve soil structure, water availability and remediate soil health issues caused by acidity and contaminants such as heavy metals. Moreover, biochar’s carbon-rich composition and long residence time in the soil are ideal avenues to contribute to effective forestry and carbon sequestration initiatives. Investments in location-based biochar production can provide forest managers with additional methods to reduce woody residues or hazard trees near roads, log landings, recreational areas and to create a valuable resource that supports forest health, resilience, and economic opportunities.