Table 2: Process variables used for modelling and their correlations with residual Al and turbidity.

VariableUnitCorrelation with residual AlCorrelation with turbidity

8Intake from Lake Humaljärvim3/h−0.16−0.27
9Intake from the pikkala reservoirm3/h0.250.39
10Total intake of waterm3/h−0.033−0.07
11Aluminium feedL/h0.110.23
12Filter wash waterm3/h−0.36−0.12
13Proportion of Lake Humaljärvi/Pikkala reservoir water intake%−0.52−0.38
14Surface level of Lake Humaljärvim0.280.14
15KMnO4 of raw watermg/L0.0650.44
16Flocculation pH
17Water temperature °C−0.72−0.42
18Aluminium doseg/m30.250.46
19Aluminium dose/raw water KMnO40.052−0.08
20Flow to filter 1m3/h0,0780.03
21Flow to filter 2m3/h0,220.19
22Flow to filter 3m3/h−0.097−0.11
23Flow to filter 4m3/h0.31−0.32