Technology
How Bio Terrava makes steel-grade biocarbon by slow pyrolysis of wood residue: process, product specification, co-products and technology readiness.
How the process works
Slow pyrolysis heats wood to 450–550 °C without oxygen. About 30% of the dry mass leaves as biocarbon; the rest becomes liquid and gas that are recovered, not flared.
Receive and screen
Construction, orchard and forestry wood is inspected, metals and treated wood are removed, and the rest is chipped to size.
Dry
Chips are dried with recovered process heat, which raises yield and keeps moisture out of the product.
Carbonise
Indirectly heated retorts hold the wood at controlled temperature and residence time to reach the fixed-carbon target.
Recover
Vapours are condensed into wood vinegar; non-condensable syngas is burned to heat the retorts and dryers.
Cool, size and pelletise
Biocarbon is cooled, screened and pelletised for injection or long-haul freight, which roughly triples bulk density.
Assay and certify
Every lot is tested for fixed carbon, ash, moisture, volatiles, sulphur and phosphorus before shipping.
- 1.0 t biocarbon
- 0.3 t wood vinegar
- 2.0 t syngas and moisture, about 12.5 GJ
- 2.2–2.8 t CO₂e removal credits
- 3.3 t dry wood residue
Built to the furnace specification
Mills buy carbon against limits on fixed carbon, ash and sulphur. Clean wood residue starts low in ash and sulphur; controlled pyrolysis at 450–550 °C does the rest.
| Parameter | Bio Terrava design target | EAF charge carbon | EAF injection carbon |
|---|---|---|---|
| Fixed carbon | 82–86.5% | ≥ 80% | ≥ 85% |
| Ash | 3.5–6% | < 8% | < 5% |
| Moisture | < 3% (pelletised) | < 5% | < 2% |
| Volatile matter | 8–12% | 10–15% | < 8% |
| Sulphur / phosphorus | < 0.03% / < 0.01% | < 0.10% / < 0.05% | < 0.05% / < 0.02% |
Design targets, to be confirmed by independent assays at bench and pilot scale.
One feedstock, four revenue lines
Slow pyrolysis splits wood into a solid, a liquid and a gas. Each has a buyer, so no single market carries the plant.
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Primary product
Biocarbon for steel and silicon
Low-ash, low-sulphur charge and injection carbon for electric arc furnaces. Silicon and ferrosilicon smelters already buy wood charcoal, which gives the plant revenue while steel-mill trials run.
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Second revenue line
Carbon removal credits
Biochar that is stored durably can earn certified carbon removal credits on registries such as Puro.earth. Credits are a second revenue line on the same tonne.
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Co-product
Wood vinegar
The condensed pyrolysis liquid is sold to agriculture as a biostimulant. It needs little refining.
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Lowers operating cost
Syngas energy
Non-condensable gas fires the retorts and dryers, so the plant runs largely on its own energy, with surplus power for export where tariffs allow.
Where each technology stands
Our advanced media and co-pyrolysis technologies (THPP, Terra BPC, VASCGBC-M and BOFS valorisation) are at Technology Readiness Level 4, validated at bench scale with university partners. Four provisional patent families were filed in April 2026. We are seeking partners to build the pilot.
AMG PYRO slow-pyrolysis kiln, charcoal duty
About 100 kilns of the 10 m³/day class designed and built with Egypt’s EEAA; 10, 34 and 45 m³ units in operation. Steel-grade output from Ontario feedstock is what the pilot will prove.
THPP, Terra BPC, VASCGBC-M, BOFS valorisation
Validated at bench scale with university partners. Four provisional patent families filed April 2026. Seeking pilot partners.
TRL 4: validated in the laboratory. TRL 6: demonstrated at pilot scale. TRL 9: proven in commercial operation.
Ask for the technical summary
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