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.
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.
The Chimney Section Grate Drying space for Slurry Plan FIG.
Fresh slurry is run on to the drying floors, and the kiln is started.
An ordinary kiln, which will contain about 50 tons of slurry and 12 tons of coke, will take two days to get fairly alight, and will be another two or three days in burning out.
The drying of the slurry is generally effected by the waste heat of the kilns, so that while one charge is burning another is drying ready for the next loading of the kilns.