Problem 3

The proximate analysis of copper concentrate  is as follows:

. The concentrate is smelted in a furnace in presence of iron ore and limestone. The analysis of iron ore is  and  and that of limestone is and . The grade of matte is  and the ratio of  in slag is . The oil amounts to 12%%of the charge and analyzes 85% carbon and 15% hydrogen. The air used is 10% excess than theoretical required for smelting
Calculate (per tonne of concentrate):

a) Weight of each flux and weight of slag.

b) Volume of air and % composition of gases. 

As said in lecture 20, fluxes are used in matte smelting to facilitate slag formation and removal of SiO₂.
Let x kg iron ore y kg limestone and z kg slag.
One can perform  and iron balance

We can form 3 equations with 3 unknown.

Volume of air:
Air used for combustion and oxidation of sulphur to SO₂ and


Assuming complete combustion, combustion reaction





Oxidation reactions are





Theoretical  required from  or iron ore.

of theoretical air.

It is advisable that the reader should calculate using the above balances.



Composition of gases

Conclusion:

in this lecture technique to solve material balance problems in matte smelting is illustrated. There could be other procedure also which may be simpler that what presented here. The lecturer of this course would be extremely happy if the reader innovate any new procedure to solve the problems.

References

1. Ray, H.S; Sridhar, R and Abraham, K.P: Extraction of non ferrous metals.
2. Rosenquist : Principles of extractive metallurgy
3. Butts, Allison: Metallurgical Problems, McGraw Hill Book Company, 1943