| Process type | Reactor type | Examples of equipment manufacturers | Advantages | Disadvantages |
| Batch | Earth pits and mounds Brick, concrete and double metal kilns Retorts |
| Simple technology, cheap and portable | Inefficient leading to low yield; no heat recovery, significant feedstock burn off; release of pyrolysis gas and vapors to atmosphere resulting in environmental pollution |
| Continuous | Retort | Lambiotte retort | The operating time for the retort-kiln is much shorter, about 12 h (plus about 12 h for cooling) | High investment costs and not viable for traditional charcoal makers in the so called south countries |
| Multiple hearth reactors |
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| Screw type pyrolysers | Pyro-7 by Pro-Natura; Biofuel Energy Systems Ltd. | Higher yields; feedstock flexibility; heat integration; possible cogeneration of char and energy; easy to operate, relatively proven technology; combined char and energy generation; available as either portable or stationary unit (depending on size) | More complex systems; more expensive than batch processes; No usable by-products | |
| Paddle drum type reactors | BEST Energies, Australia | Relatively proven technology; feedstock flexibility; combined char and energy generation; available as either portable or stationary unit (depending on size); higher yields, heat integration and possible cogeneration of char and energy | More complex systems; more expensive than batch processes |