Treatment of light polluted wastewater from cotton knitting dyeing and finishing by coagulation-ozone oxidation process with wastewater source separation
清浊分流条件下的混凝-臭氧处理棉针织印染清废水

After the wastewater discharge characteristics from the different cotton knitting dyeing and finishing production process in textile factory were investigated, source separation between the light and heavy polluted wastewater was proposed. Aimed at increasing reuse rate, the process availability using the coagulation-ozone oxidation for treating the light polluted wastewater was conducted. The results showed that the 25% ~ 30% of total wastewater amount was light polluted wastewater and mainly washing water; and the best removal rates of COD and color were over 71% and 98%, respectively, under using coagulation and ozone combined process with pH at 6~9, PAC dosage of 48 mg/L, PAM of 1.0 mg/L, and ozone concentration of 14.5 mg/L with 12 min contact time. Practice has proved that the treated water met the water quality demands of dyeing and finishing very well.