Experimental Study On Combination Of Fenton-NaClO To Advanced Treat Papermaking Wastewater

Papermaking wastewater is mainly high concentration organic wastewater with the characteristics of large discharge, high load of pollutant, complicated components, and high toxicity. Direct deposing of wastewater dose not only produce serious pollution to the environment, but also threat to the health.Although the quality had been improved after flocculation and biological treatment, some indicators of contamination were still high. So advanced treatment was needed.The typical advanced treatments had some deficiencies. However, the practicability of advanced oxidation processes in dealing with the papermaking wastewater had been confirmed by many previous research. In this thesis, Fenton reagent and NaClO oxidation were adopted to treat the wastewater, and the best running condition was confirmed. The removal rates of CODcr and chrominance as the evaluation criterion identify the advantages and weaknesses of the two methods. Based on that, combine both methods, change the order of both methods, and confirm the optimum order and technology programs.The experimental results show that:While the additiveamount of NaClO was 10ml/L, the pH value was9,and the reaction time was 60min,the best removal rates of COD and chrominance were 47.9% and 77.8%, respectively.While the Fenton reagent amount of FeSO4 and H2O2 was 7.5ml/L and 1ml/L respectively, the pH value was 4, and the oxidation time was 50min,the best removal rates of COD and chrominance were 54.4% and 74.4%,respectively.In the combination of NaCIO oxidation and Fenton reagent, after a pretreatment of NaClO oxidation, the Fenton method was used for further processing. Under optimum conditions, the removal rates of COD and chrominance were 67.9% and 93.3%,respectively. The residual concentrations of COD was 61.9mg/L.Meanwhile, In the combination of Fenton reagent and NaClO oxidation, after a pretreatment of Fenton method, the NaClO oxidation was used for further processing. Under optimum conditions, the removal rates of COD and chrominance were 71.5% and 91.3%, respectively. The residual concentrations of COD was 54.2mg/L.The combination of Fenton reagent and NaClO oxidation to treat the papermaking wastewater can reach the first grade the Haihe River Basin water pollutant discharge standards. It is recommended as the best technical solution.