Article

Pretreatment of stabilized leachate using ozone/persulfate oxidation process

Chemical Engineering Journal (Impact Factor: 3.47). 01/2013; 221. DOI: 10.1016/j.cej.2013.02.038

ABSTRACT A combination of ozonation and persulfate ðO3=S2O2� 8 Þ was used to treat stabilized landfill leachate. COD,
color, and NH3–N, ozone and persulfate doses, pH and reaction time were evaluated to define the optimum
operational conditions. The results indicated that under optimum operation conditions (i.e.
210 min of ozonation, a COD=S2O2� 8 ratio (1 g/7 g), and pH 10), the best removal values of COD, color,
and NH3–N were 72%, 93%, and 55%, respectively. The biodegradability (BOD5/COD ratio) has improved
from 0.05 to 0.29. The ozone consumption for COD removal was 0.76 kg O3/kg COD. The results obtained
by employing the combined use of persulfate and ozone were compared with those by employing ozone
only and persulfate only. The results achieved with the combined use of persulfate and ozone were compared
with those obtained with ozone only and persulfate only. The combined method (i.e., O3=S2O2� 8 )
achieved higher removal efficiencies for COD, color, and NH3–N compared with other studied applications.
Additionally, the combined of ozone/persulfate method proved to be more efficient than the combined
use of ozone/Fenton in advanced oxidation processes in the treatment of the same studied leachate.

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