Technologies for Treatment of Zinc-Containing …
803
Technological Line for Treatment of Secondary Materials
Capacity of the Waelz kilns
The capacity of the Waelz kiln is shown in Fig. 5.
Main materials for the Waelz kilns
In general, we use four types of secondary materials for the Waelz kilns:
• Own cakes—from iron precipitation in the leaching process.
• EAF dusts.
• Slag from the Ausmelt furnace in the lead plant.
• Other oxide materials.
The chemical composition of the feed materials is shown in Table 1.
Types of Waelz feed and obtained Waelz oxides
Three types of feed are prepared for the Waelz kilns:
• Feed from own cakes—based on own cakes with the addition of other oxide
materials in order to optimize the zinc content in the feed.
85,000
95,000
100,900
111,550
104 950
127,700
120 000
128,700
0
20,000
40,000
60,000
80,000
100,000
120,000
140,000
until 2011 inc. 2012
2013
2014
2015
2016
2017
2018
t dry
changing the
brick lining of 2
big waelz kilns
downtime for
reconstruction
of waelz kiln 1
Fig. 5 Capacity of the Waelz kilns