Figure 5

Effect of recycling rates on COD reduction during catalytic ozonation under continuous mode. Experimental conditions: (a) without addition of PAM; ozone dosage = 10.2 g-O3/min; HRT = 30 min; (b) with addition of PAM; ozone dosage = 10.2 g-O3/min; HRT = 30 min; (c) with addition of PAM; ozone dosage = 6.8 g-O3/min; HRT = 60 min.