ANNUAL REPORT 
516 
Per cents. 
32.55 
SWUCBogoeod 
1.93 
1.10 
62.49 
Alumina... 
Ferrie oxide..... 
Calcium oxide...... 
1.93 
Magnesium oxide...... 
The Dietzsch vertical cement kiln. 
Fig. 58. 
According to him the cement burnt in a shaft kiln requires 80,000 - 
while by fusion the same amount of 
large calories per 220 pounds, 
corresponding to the crushing and grinding must be deducted. 
cement could be produced with 200,000 calories, from which the heat 
energy 
It will be found necessary quite frequently, in fact 
nearly always, to dry the coal in a rotary dryer before pulverizing it. 
Coal Grinding. 
