Education of the republic of uzbekistan tashkent state technical university named after islam karimov

UDC 669.531.6 
INVESTIGATION OF SOLID-PHASE REACTIONS OCCURRING DURING THE 
FIRING OF CHARGE COMPONENTS 
 
B.T. Berdiyarov
1*
, A.S. Xasanov
2
, J.B. Ismoilov
1
 
1
Tashkent State Technical University, 100095, Tashkent, Uzbekistan 
2
JSC "AMMC", 53 Amir Temur Street, Almalyk, Tashkent region, 
Republic of Uzbekistan
 
 
Abstract.
This article provides information on the formation of substances formed during the 
firing of zinc concentrates and adversely affect the subsequent stages. The effect of the number of 
zinc ferrites and silicates formed due to the firing process by the addition of lime and substantial 
metal oxides to the shale has been studied thermodynamically. Thus, “strong” basic oxides and 
“strong” acidic oxides form the most thermodynamically vital compounds, and “weak” basic 
oxides with weak acidic ones form thermodynamically unstable chemical compounds. Based on 
this, it can be assumed that introducing "strong" basic oxides into the roasting mixture will 

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Geological Engineering
131 
decrease the formation of ferrites and zinc silicates. CaCO
3
as an additional additive to the 
firing charge is justified because, at firing temperatures, calcium carbonate decomposes with the 
formation of calcium oxide and carbon dioxide, which are directly involved in preventing the 
formation of ferrites and zinc silicates. To determine the optimal parameters of zinc batch firing 
with the addition of CaCO
3
as an additional component to it, we performed thermodynamic 
calculations to determine the change in the free energy of the reactions of the interaction of the 
main features of zinc concentrates and limestone at temperatures of 945-995 °C, covering the 
conditions of firing in the RL furnace. The study found that zinc ferrites and silicates can be 
significantly reduced by adding lime to the shale from an economic point of view.