472
K. Tang et al.
Table 1 Phase compositions
Phase compositions
Mass fractions (%)
PbS
37
ZnS
5
CuFeS 2
1
FeS 2
4
Fe 7 S 8
10
CaO
30
CaCO 3
1
SiO 2
9
C (coke)
3
Total
100
Table 2 Major reactions
Chemical reaction formula
2PbS + 3O 2 = 2PbO + 2SO 2 2ZnS + 3O 2 = 2ZnO + 2SO 2
FeS 2 + O 2 = FeS + SO 2
2FeS + 3O 2 = 2FeO + 2SO 2
Fe7S8 + O 2 = 7FeS + SO 2
4CuFeS 2 + 5O 2 =
2Cu 2 S+2FeS+4SO 2 +2FeO
2Cu 2 S + 3O 2 =
2Cu 2 O + 2SO 2
C + O 2 = CO 2
CaCO 3 = CaO + CO 2
2FeO + SiO 2 = 2FeO · SiO 2
The local mass fraction of each species, Y i , through the solution of a convectiondiffusion equation for the ith species. This conservation equation takes the following
general form:
∂
∂t
(ρY i ) + ∇ · (ρvY i ) = −∇ · J i + R i + S i
(7.1)
where R i is the net rate of production of species by chemical reaction (described later
in this section) and S i is the rate of creation by addition from the dispersed phase
plus any user-defined sources.
The reaction rate: R i,r is given by the smaller of the two expressions below:
R i,r = v
i,r M w,i Aρ
ε
k
min
R
Y R
v
R,r M w,R
R i,r = v
i,r M w,i ABρ
ε
k
N
p
Y P
N
j
v
j,r M w, j
(4.24)