A comparison of results obtained in this study and previous studies is shown in Table 3. The performance of the extracted coagulant was tested in the different levels of turbidity; low, medium and high while other studies tested only one level of turbidity. Coagulants from this study performed quite higher than those in comparison as shown in Table 3. This is because the WTS used in this study has high Al and Fe content, which are very significant for coagulation compared to the WTS used by the other researchers. For instance, WTS used in this study had an Al content of 20.3% compared to the 9.58% used by Tarique et al. (2016). It also had 5.28% Fe content compared to 1.35% of Fe content in the WTS used by Chigondo et al. (2015). Further tests done with the real water sample, with elevated levels of turbidity, still indicated high levels of turbidity removal (97%). This shows the effectiveness of the coagulant obtained in this study and its potential for application in a typical WWTP. Thus, an effective environmentally benign method for preparing WTS coagulant has been achieved without compromising the water clarification levels.
Comparison of experimental results from this study to those of previous studies
. | Experimental data from this study . | Tarique et al. (2016) . | Chigondo et al. (2015) . | Sanga et al. (2018) . | |||
---|---|---|---|---|---|---|---|
Raw water turbidity (NTU) | 20 | 50 | 80 | 381 | 35 | 16.7 | 89.7 |
Treated water turbidity (NTU) | 0.42 | 0.04 | 0.4 | 11.35 | 5 | 6.4 | 1.2 |
Extracted coagulant's dosage (mL/L) | 2 | 3 | 5 | 5 | 8 | 0.04 | – |
% Reduction | 97.9 | 99.9 | 99.5 | 97.0 | 85.7 | 61.7 | 98.7 |
. | Experimental data from this study . | Tarique et al. (2016) . | Chigondo et al. (2015) . | Sanga et al. (2018) . | |||
---|---|---|---|---|---|---|---|
Raw water turbidity (NTU) | 20 | 50 | 80 | 381 | 35 | 16.7 | 89.7 |
Treated water turbidity (NTU) | 0.42 | 0.04 | 0.4 | 11.35 | 5 | 6.4 | 1.2 |
Extracted coagulant's dosage (mL/L) | 2 | 3 | 5 | 5 | 8 | 0.04 | – |
% Reduction | 97.9 | 99.9 | 99.5 | 97.0 | 85.7 | 61.7 | 98.7 |