How to Use a Retort Kiln to Make Charcoal
- 1). Fill the chambers of the kiln with wood or other selected organic matter. Pack the trays or buckets that go into the chambers as densely as possible.
- 2). Close the retort completely. If your kiln is pre-fabricated, follow the instructions for closing it off; if you built your own, make sure all covers are secured and that no outside air can enter the chambers.
- 3). Build a fire beneath the chambers, utilizing twigs, foliage, roots and bark as kindling. Keep your quality wood pieces for later batches of charcoal.
- 4). Allow the fire to burn for about three hours. By this time, the gases and tar start emitting from the embers. The gases continue to fuel the conflagration until the transformation to charcoal is complete.
- 5). Wait for the gases to stop flowing from their outlet. This signals that the fire is done. Leave the kiln shut until the following morning.
- 6). Open the doors or covers of the retort and remove the containers of charcoal. Disperse the charcoal and let it cool for three more hours.
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