Comparison of conventional and catalytic ozonation for the treatment of pulp mill wastewater

The present study deals with the application of the catalytic ozonation process TOCCATA(R) as tertiary treatment of pulp mill effluent. The first series of experiments conducted in a semibatch mode allow comparing the reactivity of seven organic pollutants commonly found in pulp mill wastewaters during conventional and catalytic ozonation. The results obtained highlight the benefits provided by catalytic ozonation, compared to direct ozonation, particularly in term of rates of TOC and COD abatement. The comparison of both oxidation systems for the treatment of a biological pulp mill effluent shows similar effects. Finally, the performances of the catalytic ozonation process are fully demonstrated through continuous mode testing. The overall results show the suitability of catalytic ozonation process as a tertiary treatment.