19 Evaluation and Optimization of the Treatment Scheme …
207
Table 19.5
Decision matrix
Alternatives
Pretreatment
Biological treatment
Pretreatment
Footprint
Chemical
use
Sludge
from plain
setting
Sludge from
chemical
setting
COD
removal
TSS
removal
Metal
removal
Biological
treatment
footprint
Energy
consumption
Sludge from
biological
treatment
1. Alternative 5
5
3
5
1
1
2
1
1
1
2. Alternative 4
3
2
3
4
4
5
4
4
4
3. Alternative 5
2
5
1
2
3
5
2
2
2
4. Alternative 3
1
1
3
5
5
5
5
4
4