Taguchi-Based Process Optimization for Improving Iron Removal …
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the parameters affecting in EC. From Delta-Rank, we can see that initial concentration of iron is the most significant parameter followed by electrode distance, current
intensity, initial pH, and conductivity (initial concentration > inter-electrode distance
> current intensity > initial pH > conductivity).
3.2 Effect of Various Parameters
To investigate the effect of various parameters like initial concentration of iron,
current intensity, pH, inter-electrode distance, and conductivity on the removal efficiency of iron by electrocoagulation process, L 16 experiments were carried at a fixed
time.
3.2.1 Effect of Initial Concentration of Iron
Effect of initial concentration of iron is one of the most significant factors affecting
the electrocoagulation process. Under reaction conditions of reaction temperature =
30 °C, reaction time = 40 min, monopolar connection of aluminum electrodes and
agitation speed = 400 rpm, maximum removal efficiency of iron was obtained at
15 ppm of initial iron concentration, as demonstrated in Fig. 2. Figure 2 reveals that
with an increase in initial concentration of iron the removal efficiency decreases. This
is due to the fact that the time of each electrocoagulation was limited to 40 min and
as the amount of iron increased the S/N ratio decreased. The maximum removal was
observed at 15 ppm (S/N ratio: 37.33) and the least was at 30 ppm (S/N ratio: 36.03).
At lower concentration (up to 15 mg/L), available aluminum hydroxide complexes
are adequate to remove the Fe(II) molecules within 40 min with appropriate oxidizing
14
16
18
20
22
24
26
28
30
32
35.6
35.8
36.0
36.2
36.4
36.6
36.8
37.0
37.2
37.4
S/N Ration
Initial Concentration (ppm)
Fig. 2 Removal efficiency of iron versus initial concentration of iron by monopolar electrocoagulation process
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the parameters affecting in EC. From Delta-Rank, we can see that initial concentration of iron is the most significant parameter followed by electrode distance, current
intensity, initial pH, and conductivity (initial concentration > inter-electrode distance
> current intensity > initial pH > conductivity).
3.2 Effect of Various Parameters
To investigate the effect of various parameters like initial concentration of iron,
current intensity, pH, inter-electrode distance, and conductivity on the removal efficiency of iron by electrocoagulation process, L 16 experiments were carried at a fixed
time.
3.2.1 Effect of Initial Concentration of Iron
Effect of initial concentration of iron is one of the most significant factors affecting
the electrocoagulation process. Under reaction conditions of reaction temperature =
30 °C, reaction time = 40 min, monopolar connection of aluminum electrodes and
agitation speed = 400 rpm, maximum removal efficiency of iron was obtained at
15 ppm of initial iron concentration, as demonstrated in Fig. 2. Figure 2 reveals that
with an increase in initial concentration of iron the removal efficiency decreases. This
is due to the fact that the time of each electrocoagulation was limited to 40 min and
as the amount of iron increased the S/N ratio decreased. The maximum removal was
observed at 15 ppm (S/N ratio: 37.33) and the least was at 30 ppm (S/N ratio: 36.03).
At lower concentration (up to 15 mg/L), available aluminum hydroxide complexes
are adequate to remove the Fe(II) molecules within 40 min with appropriate oxidizing
14
16
18
20
22
24
26
28
30
32
35.6
35.8
36.0
36.2
36.4
36.6
36.8
37.0
37.2
37.4
S/N Ration
Initial Concentration (ppm)
Fig. 2 Removal efficiency of iron versus initial concentration of iron by monopolar electrocoagulation process