In this study, tests were performed to examine the effects of with/without chloride addition, electrolyte(NaCl vs. Na2SO4), anode material (boron-doped diamond (BDD) vs. PbO2), current density (0.10?0.50 A/cm2), and anode area (2?6 cm2) on the electrochemical abatements of organic pollutants (interms of total organic carbon (TOC) or chemical oxygen demand (COD)) and ammonia nitrogen inswine wastewater. The results showed that the TOC degradation was greater in the absence of chloride,but an opposite trend was observed for NH3-N electrochemical abatement. A similar phenomenon wasalso observed when replacing chloride with sulfate. In the presence of chloride, the NH3-N removalefficiencies were similar on BDD and PbO2, although the former anode was better for TOCdegradation than the latter. The removal of both COD and NH3-N increased with increasing currentdensity or anode area on BDD. During the electrolysis of the wastewater, nitrite was not detected in thepresence of chloride except in the absence of chloride, in the presence of Na2SO4, or on PbO2 at 0.25A/cm2 and on BDD at 0.50 A/cm2 in the presence of chloride. In the presence of chloride, theconcentration of nitrate increased and then decreased with increases in electrolysis time for almost allthe tested conditions. At 25oC and 0.25 A/cm2, the pseudo-first-order rate constants for COD and NH3-N removal were 7.05×10-4 and 6.40×10-4 1/s, respectively, while the general current efficiency andspecific energy consumption were 15% and 9 kWh/kg-COD, respectively on BDD (4 cm2).
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