228
L. Ren et al.
Table 7.1
Pollutant discharges per ton of finished steel in iron and steel plants (kg/t finished steel)
Pollutant
Factor
Sintering
Coking
Ironmaking
Steelmaking
Steel rolling
Comprehensive
Total
Particles
Dust
3
1
2
0.5
0.6
–
7.1
Smoke dust
Fume
Sox
4
0.3
0.32
0.2
2
–
7
Nox
1
0.2
0.2
0.1
0.5
–
2
CO
40
0.3
5
15
0.33
–
60.63
HF
0.04
Trace
Trace
0.01
Indefinite
–
0.05
CxHr
0.1
0.2
0.05
0.05
0.2
–
0.6
Waste water
SS
0.28
0.06
0.24
0.07
0.2
–
0.85
COD
0.05
0.08
0.16
0.2
0.14
–
0.63
NH3
–
0.03
0.08
–
–
–
0.11
Phenols
–
0.005
–
–
–
–
0.005
Cyanides
–
0.02
0.03
–
–
–
0.05
Chlorides
–
–
0.05
0.05
0.2
–
0.3
Sulfates
0.004
–
0.003
–
0.4
–
0.407
Solid waste
Dust
Reuse
2
12
30
–
–
79
Sludge
12
15
10
–
Residue
–
–
300
100
–
–
400
Iron oxide scale
–
–
–
–
30
–
30
(continued)