adam + partner appropriate technology
adam + partnerappropriate technology

"Adam Box-Kiln"     (new)

A new Box-Kiln was developed in 2019/ 2020
more information will follow soon....










The main advantage of this
Box-Kiln will be that only one person can operate it.
The weight to lift the cover is reduced to about 30kg- thanks to the counterweights














Starting the Box-Kiln operation by enkindling a fire in the front.

A one-day operation is possible













2 detachable insulation lids are placed on the top to increase the efficiency of charcoal production.
Further insulation lids for the 3 sides are optional.
















Comfortable loading of the wood

comfortable harvesting of the charcoal
thanks to the removable cover.

"It's fun to operate this kiln!",
-once you lift the cover- You have a gift of charcoal to your feet!



A successful installation of the
at Ghana for giz (Forest Project,
Mai 2021)


Candling of the wood
to start operation


Average data:

Volume Box: 2m x 1m x 1,73m = about ~3,5m³

Effective volume of wood loaded: 1,9m x 0,9m x 1,6m = ~2,74m³

Weight of wood: about 650kg and about 20% humidity (~130kg of water)

Weight of wood oven dry: ~520kg

Charcoal received: about ~150kg

EFFiCiENCY: about ~29%

Operation time: about 12 hours
Cooling time: about 1 night and 1/2 day

Construction costs: about 500€ - 900€ depending on the country


Weight of bamboo: about 338kg and about 17% humidity (~57kg of water)

Weight of bamboo oven dry: ~274kg (7kg not carbonized)

Bamboo Charcoal received: about ~74kg

EFFiCiENCY: about ~26%




Steel Ring Kiln (MARK-II)
widely promoted by

but never really accepted by its owners...


A Ring Kiln needs several people to lift the cover or the lid.
It's an arduous task to climb inside the vessel and to load
or to harvest the charcoal.

This Box-Kiln should replace the common Ring-Kiln made from a round metal sheet.

This is not a retort kiln which burns most of the volatiles-
however, it might be possible to integrate an afterburner?

This Box-Kiln was filed under Intellectual Property Protection (patent) and the Box-Kiln should not be build without the inventor's consent (Ch.ADAM).


Check my YOUTUBE Video Clip on the Box-Kiln:


Round steel kiln (Ring Kiln)


Box-Kiln  (adam-design)

disadvantages advantages  

Complicated Construction: needs a sophisticated metal workshop, as a roller-sheet bending machine is needed to bend large metal sheets into a circle shape.

Simple Construction: simple construction in any village workshop, just (extensive) welding and no sheet needs to be cut.


Operation by more persons: it needs 2 or more persons to lift and remove the lid and upper ring of a round steel ring.

Operation by a single person: a single person can tilt the Box-Kiln because of the counterweights to ease tilting (option: if money needs to be saved, skip the counterweights)  
Biomass (wood) needs to be cut short into short pieces of different length- according to the variation of a cross-section of the kiln. Biomass (wood) can be used in one standard length (about 2 meters).  

Medium efficiency which is not really enough to justify and benefit all the investment

Higher efficiency because of the top of the Box-Kiln can be easily insulated by a removable lid/cover. For quick cooling, the lid/cover can be removed.


Medium volume (2,5m³) for filling with biomass

High volume for filling with biomass, about 4m² if 1m x 2m metal sheets are used


Difficult access to recover the charcoal, as the charcoal needs to be taken out from the deep hole if the kiln.

Easy access for loading the biomass and offloading of the charcoal, as the box will be tilted upwards to ~90°

dt. With some small modification- trials for an integrated afterburner within the box can be made- for clean combustion of the wood gas  


Box-kiln can be loaded on a pick-up f transport



Quick construction within a few days



Already registered under the “Intellectual Property Law” to save the project's investment.

HORNO CEVAG (Fabricación de carbón vegetal)


At least 3 workers are needed to mantle, to reassemble a ring-kiln together. Here a ring-kiln operated in South America.

charcoal / Creating a charcoal burn


At least 3 persons are needed to place or lift the lid of a ring-kiln. Here a ring-kiln operated in UK.


Just for comparison :
A professional charcoal producer from PAKiSTAN claims a low efficiency of 10% for his brick kilns and an operation time from 12 to 15 days!
(Making Charcoal in Pakistan | How to make charcoal).
He claims to buy the wood and sell the charcoal for 10 x more (increase in value) ....

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