Material balance
Hot metal of composition 0.8% Si, 0.2% P, 0.25% Mn, 4% C and rest iron is refined in a converter to produce steel of composition 0.1% C and rest iron. Pure oxygen is blown. During refining scrap is charged whose amount is 15% of hot metal. The composition of slag is CaO  and  with CaO Exit gases analyses  and  . Calculate amount of steel, slag, oxygen and waste gases per ton hot metal.
Basis: 1000 kg hot metal.
| Fe balance: Let X kg is mass of steel and Y kg mass of slag |
(3) |
Mn balance:
| Mn in hot metal = Mn in slag |
(4) |
Mn in hot metal = Mn in slag
Putting the values in 3 and 4 we get.
X = 1080.68 kg steel
Y = 126.7 kg slag.
Carbon balance:
| C in hot metal + C in scrap = C in steel + C in waste gases |
(5) |
C in waste gases = 39.07 kg
C in 
C in 
Exit gas volume  (1 atmospheric pressure and 273K).
 required can be calculated from Si, C, Mn and Fe balance.
Calculations give  (1atmospheric pressure and 273K)
Material balance gives an idea of the charge materials required.
For example 100 ton capacity would require approximately 93 tons hot metal and 10 ton scrap. The amount of slag would be 12 tons and total oxygen required would be  . The volume of exit gas is . These are the approximate values and are given to develop a feel of the converter design.
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