Electrocoagulation-flocculation (ECF) of fish pond wastewater was examined
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Optimum pollutant removals were obtained at pH of 2 using Al-Al, Fe-Fe, Al-Fe and Fe-Al
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Fe-Fe electrodes were the best for reducing COL (73.56%).
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Al-Al were seen as FPW's best BOD removal (76.90%), COD removal (86.4%) and TUR removal (87.87%) electrode
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The process partially fitted to the theory of flocculation proposed by von Smoluchowski
Abstract
This work investigated the treatment of fish pond wastewater (FPW) using electrocoagulation – flocculation (ECF) through aluminium (Al) and iron (Fe) electro-coagulants. The feasibility of using this method has been determined in terms of turbidity (TUR), biochemical demand oxygen (BOD), chemical demand oxygen (COD), and reduction of colour (COL). The study analysed the role of pH, current dosage, electrolysis time, settling time, temperature, and concentration of NaCl on the ECF process. Also, the influence of using the hybrid of Al and Fe in different configurations (Al-Al, Fe-Fe, Fe-Al, and Al-Fe) was taken into account for the ECF process. The perikinetics kinetics of the process flocculation was studied. The coefficient of regression (R2) was used to confirm the theoretical applicability of perikinetics flocculation. The forecast of the time evolution of aggregating particles or species was included. The optimum pH was 2. Al-Al electrode had a higher TUR removal (87.87%). Fe-Fe electrodes were the best for reducing COL (73.56%). Al-Al was proven to be the best electrode configuration for BOD removal (76.90%) and COD removal (86.4 %). The ECF kinetic data partially followed Von Smoluchowski's equation for the Brownian perikinetics flocculation theory. The mechanisms that accounted for the distribution of particles were sweep flocculation and charge neutralisation. The ECF was very effective for reducing FPW pollutants.
