The thatched hut where bricks are made.
A batch of 50 bricks are just dry enough to put into the kiln
This is done in crisscrossing layers of 10 bricks
The bricks are then covered in old broken tiles and pot sherds to keep the heat in
With the floor space empty, another batch of bricks is prepared
Clay is placed in a brick mold (made from fired clay itself) to form a 25 x 12.5 x 6.25 cm brick
Every couple of bricks, the mold is wetted to help the clay slide out more easily
Making fire with fire sticks
A fire is lit in the kiln
The roof keeps the rain off the bricks being fired, the bricks drying on the floor and the fire wood
The smoke diffuse through the thatch, helping to preserve it against rot
We can see the bricks getting red hot through the gaps indicating a good firing
The next day, the cool bricks are taken out
The pile of bricks
The next batch of bricks to be fired
Here I changed the kiln design to have 3 firing ports instead of 2
Primary air flows in through the 3 lower ports while wood is put through the 3 upper ports
Bricks are taken out the next day and added to the pile
Ash is taken out of the kiln to be used for cement at a later stage
The ash is wetted to form a paste
It is then formed into bricks for storage
When needed, the ash bricks will be fired in the kiln to calcine them and then mixed with water and sand to form a mortar
More clay for bricks is dug
The clay is placed in a pit where it will be slaked ready for making bricks
Water is added to the 25 pots loads of clay
Clay is put onto the floor to make bricks
It takes about an hour to make 50 bricks
The kiln is daubed with clay to keep in the heat during firing
The bricks are turned to help them dry faster
When the bricks are semi dry they can be put into the kiln (though it's better for them to be completely dry before firing)
So a drying fire is lit the day before the actual firing takes place
The moisture slowly escapes so that the bricks won't spall due to steam explosions in the proper firing
Stacking the kiln's upper ports with wood
lighting the fire in the lower port
The kiln is stoked for 2.5 to 3 hours
Bricks are taken out the next day
Again the ash is taken out to form calcium storage bricks
It's easier to make a well in a pile of ash and wet it into a dough than it is to mix it in a pot
Any left over ash is made into a ball for storage
The growing pile of bricks
In addition to bricks, the thatched hut will be used for charcoal production, a fuel used for smelting iron
Soil is made into mud to form the charcoal kiln
A 75 cm diameter mud cylinder is formed
This is built up till it is 50 cm tall
8 air holes are then dug around the base at equal distances
A fire is lit to dry the mud
Dry, dead wood is collected and broken up to make charcoal
The charcoal is stacked into the kiln in alternating layers
Once the cylinder is full, a conical pile of wood is built on top
Finished stack
Coating conical top with mud
A small hole is left in the top to start the fire in
The fire burns back down through the hole in the top of the mound
The wood slowly carbonizes to charcoal due to incomplete combustion
When the fire front reaches an air entry, it is plugged with mud
Each hole at the base is plugged when fire can be seen through it
When the last air entry is plugged, the air exit at the top is plugged also
The whole process takes about 3 hours
The next day, the conical top is broken open
Most of the wood has become charcoal
A wicker sieve is used to grade the charcoal. The finer coals fall through while the larger coals roll into the pot
The charcoal is taken to the brick hut to be used for smelting
6.5 pots of charcoal were made in this firing
A later batch made 9.5 pots of charcoal due to better stacking
Charcoal being used for smelting iron ore
Yet more bricks added to the pile
About 250 bricks
9 ash bricks as a source of calcium for making mortar later
Brick, mortar and charcoal production factory