I believe that the future of low-cost biochar production at the farm scale requires a fresh approach. My solution is for farmers, small enterprises, and interested parties to pilot:
✳️A “TUNNEL kiln” or
✳️A cheaper “ONE-drum” version.
Previously, we designed and prototyped the following kilns and devices with my own funding, international donor money, and client funds:
✳️A charcoal gasifier camping stove (patented and exhibited at the Popular Mechanics INVENTORS conference, 2009).
✳️The “3-drum Biochar Retort,” funded by EEP-S&EA through the Vuthisa Biochar Initiative, featured in the “Assessment of the Potential to Produce Biochar and Its Application to South African Soils as a Mitigation Measure,” funded by the Department for International Development (DFID), 2015.
✳️A “Progressive Batch” Biochar System for pyrolyzing faecal sludge in East London (2018 – 2020), funded by the Bill and Melinda Gates Foundation.
✳️The “REC Biochar Retort,” built and tested by a client in Johannesburg.
✳️The “Mini Oven Biochar Retort,” delivered to a client in Victoria Yards, Johannesburg.
We were involved in the development and testing of the Biolyser Mobile Reactor, where I currently serve as a trainer.
Not yet prototype-tested:
The “Black Ripple” Biochar Retort, designed in collaboration with a client in the USA who has been using the same Vuthisa “3-drum retort” since 2011 and suggested modifications.
New Design Brief: The goal is to conceptualize a system that can be built by hand without needing cement or permanent infrastructure, which can be extended in length according to the client’s budget. This system aims to compete with established models like the Adam Retort, which can cost upwards of $10,000 to build and is a permanent fixture. Provisional costing (without profit added) estimates the “TUNNEL kiln” at $8,300 and the “ONE-drum” at $3,000. The cost of creating one-time mold sets is estimated at $661.
All these ventures have provided me with valuable insights into the thermodynamic processes involved in making biochar by combining 55-gallon drums with rocket stove heating. Since then, I have focused on scaling this system down to meet farm-scale economics. To ensure the longevity of production equipment and enhance efficiency, bona fide biochar kilns wishing to compete with industrial systems require high-density firebricks, fiber plaster, kaowool blanket insulation, and a sturdy metal frame structure with a roof. However, this represents a costly investment that many farmers are reluctant to make.
A fortuitous phone call from a refractory specialist led to a collaboration aimed at developing a “LEGO block” system, where the pre-fired block structure serves as both insulation and support. We conducted a cost-benefit analysis showing that this approach is approximately 50% more affordable and easier to install. Additionally, the parts are modular and can be “added to” over time to increase production capacity. We have prepared a concept document.
Join Tier 2 LIONS on our Patreon to view the full document and receive future updates. Please note that our intellectual property is protected; thus, you will need to sign an NDA to gain full access to the final plans. For now, we will provide carefully selected progress reports on projects (with their permission) as their pilot programs are rolled out. If you are part of an educational entity or have grant money or budget available for building a pilot, consider ordering the LEGO blocks from us.
BKI 