BBQ charcoal making process

1. Traditional charcoal making process (earth kiln method)

• Select hardwood (oak, fruit wood, etc.) or bamboo, cut into wood sections with a length of 30-50cm and a diameter of 5-15cm, and dry them naturally until the moisture content is ≤20%.
• Stack the wood vertically in the earth kiln, cover the top with soil/refractory bricks to seal, leaving only the bottom air inlet and the top smoke exhaust hole.
• Ignite the bottom fuel to evaporate the moisture of the wood, which takes 20-30 hours.
• Close all pores and cool naturally for 3-5 days until the kiln temperature drops below 50℃.
• Take out the charcoal blocks, remove the incompletely carbonized debris, and classify and package them according to size.
• Advantages: low cost, suitable for small-scale production, retaining natural wood fragrance.
• Disadvantages: low efficiency (cycle up to 5-7 days), high pollution (direct flue gas discharge), and the yield rate is only 20-30%.

2. Modern charcoal production process

• Core process (using bamboo powder/wood chips as raw materials)
• Crush bamboo, wood chips or straw to a particle size of ≤5mm and dry to a moisture content of 8-12%.
• The raw materials are mixed with a binder (starch or lignin, accounting for 3-5%) and pressed into a hexagonal prism (diameter 3-5cm) at a high temperature of 260-350℃ by a screw extruder.
• The formed rods are sent to a continuous carbonization furnace and the temperature is controlled in sections under an oxygen-deficient environment:
• 200-600℃, remove volatiles, form a fixed carbon structure, which takes 6-10 hours;
• Water cooling/air cooling to below 80℃.
• Cut into a standard length of 10-20cm, coat the surface with a combustion aid (potassium nitrate solution), and test the calorific value before packaging (≥6500kcal/kg).

Technical advantages

• High production efficiency (8 hours/batch), raw material utilization rate of more than 90%;
• Charcoal density (1.0-1.4g/cm³) can be controlled by adjusting the adhesive and temperature.

3. Smokeless charcoal production process

• The carbonization stage is extended to 48 hours to ensure that the volatile matter is fully decomposed;
• Calcium carbonate (accounting for 2-3%) is added to absorb the smoke particles generated during combustion.

4. Biomass granular charcoal

• Raw materials: waste biomass such as coffee grounds and coconut shells;
• Binder-free molding: using the raw material's own lignin to thermally bond under high pressure (100MPa);
• Carbonization temperature: 600-800℃, generating a microporous structure to improve combustion efficiency.

5. Charcoal quality control

• Fixed carbon content: high-quality barbecue charcoal ≥75% (mechanical charcoal ≥70%);
• Ash content: ≤5% (fruit charcoal) or ≤10% (bamboo charcoal);
• Volatile matter: ≤15%, too high is prone to smoke.
• Heavy metal content: lead ≤10mg/kg, arsenic ≤2mg/kg (refer to GB/T 17664-2022);
• Combustion gas detection: carbon monoxide emissions ≤0.1%.

Summary: Process selection recommendations

Small-scale/special production: traditional earth kiln + fruit wood raw materials, mainly flavored charcoal;

Scale/environmental protection needs: machine-made charcoal production line, with flue gas treatment system;