Finally, the kiln door was completely sealed, leaving only the chimney for smoke emission. By visually inspecting the color of the smoke, one can understand the stage of wood carbonization.
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After several experiments with the "small charcoal kiln," Chen Zhou summarized his experiences to improve the design and added some small features he had previously overlooked.
For example, laying some gravel at the bottom of the charcoal pit to increase ventilation during charcoal burning.
Another example is lengthening the chimney to allow smoke to be emitted higher into the sky, which not only makes the smoke color easier to observe but also reduces pollution.
A critical point is the fire prevention issue, which requires removing flammable materials near the charcoal kiln, digging firebreaks, and setting up a small shed nearby to store some water and sand—
The forest was not far from the charcoal kiln, and there was wood piled up nearby; a fire could have unimaginable consequences.
