According to present practice the raw materials are mixed in a wash mill with so much water that the resulting slurry contains 40 to 50% of water.
The slurry, in drying on the floor of the flue, forms a fairly tough cake which cracks spontaneously in the process of drying into rough blocks suitable for loading into the kiln.
Fresh slurry is run on to the drying floors, and the kiln is started.
A layer of dried slurry is loaded on this, then a layer of coke, then a layer of slurry, and so on until the kiln is filled with coke and slurry evenly distributed.
Besides the chamber kilns which have been described, there are the old-fashioned bottle kilns, which are similar, to the chamber kilns, but are bottle-shaped and open at the top; they do not dry the slurry for their next charge.