Now i have another problem. ten years ago we used only wood for burning. For reasons of cost, cutting trees, and variability we experimented ( costly) and ended up putting charcoal dust on every layer. It works very well and is cheap. I still needed some firewood to get it going. Then i found jatropha cake, the "waste" after extracting biofuel. Someone make briquettes and we can throw them into the kiln tunnels, so we decreased firewood again. We also used some jatropha briquettes in the lower layers to help the fire move up to t he charcoal dust.
It works good. New problem. Jatropha cake has a fair amount of oil left in it and the smoke is not bearable like wood and charcoal dust. Can't work in the drying sheds above the kiln those two-three days when we burn. Neighbor house is complaining.
Enter the idea to vault the kiln and add a chimney. I have no idea how to size the chimney. What i can find is complicated calculations.
Front and chimney side of kiln. on left bottom you can see part of one of the six tunnels for lighting fire.
Doors on the sides for loading and unloading. They are bricked up before firing. upper door is for monitoring the progress and also loading / unloading.
above lower door is chimney. WE will see
Tried new method of layout of the catenary arch. Hung chain and then measured every 20cm and transferred the measurements to end walls.
One end got about 2m out and then heavy truck caused many vibrations from road and one arch opened up 3mm. if it was closed would not be a problem.
Solution below is to put another layer immediately on top.
Second layer goes up fast. again clay mud mortar
The end without chimney. Will need to build stairs to upper door.
the arches. it will become black soot some day.