How to Build a Simple, Low-Cost TLUD Biochar Kiln

Building a Top-Lit Updraft (TLUD) biochar kiln is a straightforward, low-cost way to create valuable biochar while reducing smoke pollution. This DIY machine, based on the Warm Heart Worldwide design, is primarily built from a used 55-gallon steel drum and scrap roofing. It’s an efficient tool to convert biomass into biochar for your garden, animal feed, or other uses, achievable on a tight budget.

The instructions below are based on the video: How To Make A Biochar Machine – TLUD.

Materials & Tools

Materials:

200L Steel Drum: Look for used drums from local workshops or farms.
Roof Sheeting or Scrap Metal: For constructing the inner chimney stack.
Screws and Nuts: For assembling parts.
Fireproof Sealant: Optional, for sealing joints.

Tools:

Power Drill: For making holes.
Angle Grinder: For cutting metal.
Screwdriver and Pliers: For assembly.
Safety Gear: Gloves, goggles, and a mask.

Note: If you have access to a mechanic’s workshop, you might be able to borrow the tools or pay the mechanic to build the kiln, reducing costs.

Step-by-Step Construction

Step 1: Prepare the Steel Drum

Clean the Drum: Ensure it’s free from residues.
Drill Air Holes: At the bottom of the drum to allow airflow.

Step 2: Construct the Inner Chimney Stack

Cut the Roof Sheeting: Into strips.
Form a Cylinder: Wrap the strips into a cylindrical shape and secure with screws.
Install Inside the Drum: Ensure it’s centered and stable.

Step 3: Modify the Drum Lid

Cut the Lid: Create an opening at the center.
Attach the Chimney Stack: Secure the top of the stack to the lid.

Step 4: Final Assembly

Seal Joints: Use fireproof sealant to prevent air leaks.
Install Air Vents: If necessary, add additional vents for airflow.

Cost Breakdown

Item	Estimated Cost (USD)
200L Steel Drum	$10–15
Roof Sheeting/Scrap Metal	$5–10
Screws and Nuts	$2–3
Fireproof Sealant (Optional)	$3–5
Total	$20–30

Note: Prices are approximate and may vary based on local availability and sourcing.

For detailed instruction to produce high-quality biochar with this kiln, please refer to this page.

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