Multi-criteria assessment of advanced tertiary treatments for micropollutants removal
Elimination des micropolluants par les procédés complémentaires avancés
Résumé
This paper presents the removal of 64 micropollutants from wastewater by 5 tertiary treatment processes: adsorption on activated carbon, ozone, ozone/H2O2, ozone/UV and UV/H2O2. Several validated analytical methods were used and reached very low limits of quantification (ng/L) and limited uncertainties. The tertiary treatments studied in the conditions applied were found efficient for the removal of most of the compounds analyzed in this study, except metals. Activated carbon and ozone allowed the removal over 70% of 2/3 of the organic micropollutants quantified. The addition of hydrogen peroxide to ozone increased the number of substances well removed (Rw>70%), but it did not improve the removal of substances that readily react with ozone. The other AOP (ozone/H2O2 and UV/H2O2) did not improve the number of substances well removed in comparison with ozone alone. The 5 technologies studied were sized at full scale in order to evaluate their investment and operation costs for two sizes of WWTP. According to this study, the implementation of a tertiary treatment on a 60 000 or a 200 000 PE WWTP would increase the water treatment cost by 2 to 20 euros cents per cubic meter treated according to the technology, the list of analyzed compounds and the removal objective.