Rudarski radovi br 4 2011 - Institut za rudarstvo i metalurgiju Bor

Fig. 3. Technological scheme of laboratory process for smelter slag granulation<br />
4. PROCESS OF SLAG<br />
GRANULATION<br />
For laboratory experiment, the slag<br />
was used which was taken from the crushing<br />
plant from conveyor belt, before the<br />
tertiary crushing process. Slag was exposed<br />
to the weather conditions on a<br />
dump, so it contained the certain amount<br />
of moisture why it was pre-dried at room<br />
temperature. For characterization of taken<br />
sample, the chemical analysis of slag was<br />
carried out and shown in Table 1.<br />
Table 1: Chemical composition of starting slag<br />
Compound–<br />
chemical element<br />
Cu Fe3O4 CaO S Fe FeO SiO2 Al2O3<br />
Content [%] 0.68 1.754 17.26 1.07 25.69 26.75 43.76 3.89<br />
Slag was then subjected to smelting in a<br />
laboratory induction furnace, power of 100<br />
kWh, in a pot, volume V = 10 l, ELING –<br />
Loznica manufacturer. The granulation was<br />
carried out in the laboratory conditions in a<br />
pot for slag cooling. During the experiment,<br />
25 kg of slag was melted and the temperature<br />
of slag pouring was t=1250 o C. Temperature<br />
measurement was performed by the<br />
slag immersion pyrometer.<br />
In this way, the primary sample of<br />
granulated slag was obtained where further<br />
investigation of grain-size distribution,<br />
chemical composition, etc. was conducted.<br />
So, in the laboratory conditions, a<br />
possibility of smelter slag granulation was<br />
confirmed and the preconditions were<br />
formed for construction of laboratory device<br />
for granulation. This new laboratory<br />
device should provide, as the first:<br />
No 4, 2011. 103<br />
MINING ENGINEERING