Treatment Of High-salt Organic Wastewater With Activated Carbon Adsorption-Fenton Oxidation Process

High-salt organic wastewater from the production procedure of the thermal power, nuclear power, steel, metallurgy, chemical industry, medicine, fuel, printing and dyeing, paper, pesticides, et., contains not only high concentrations of dissolved organic matter, heavy metals, oils, and soluble inorganic salt of SO42-, Cl-, Ca2+and Na-and other substances, but also a variety of refractory toxic organic compounds. Once untreated high salt organic wastewater discharged into water directly, the surface water will be polluted, the microorganisms will be poisoned and the production of crops will decreased by various of diseases. At present, high-salt wastewater has gradually become a major problem in the field of wastewater treatment in China and other countries. Using the traditional physical method, chemical method and biological method for processing, always cause large scale of money and tend to fail to achieve the desired treatment effect. Also, those traditional methods may lead to secondary pollution. Therefore, developing a more effective high-salt organic wastewater treatment as an alternative to the traditional process has very important significance.This study focus on joint technical solutions to deal with high salt and organic wastewater, using activated carbon adsorption-Fenton oxidation process, namely "active carbon absorption high salt organic wastewater separation of organic matter, in the high-salt organic wastewater, introducing Fenton advanced oxidation technology while pretreating wastewater to achieve the desired treatment effect. Fenton advanced oxidation technology of activated carbon adsorption of organic matter with Fenton reagent, activated carbon assisted Fenton Oxidation removal of organic matter while the activated carbon desorption regeneration of activated carbon recycling" technology program.The coupled process of activated carbon adsorption-Fenton oxidation was applied for the treatment of high salt organic wastewater. The impacts of different factors on the treatment of high-salt organic wastewater with this technology were investigated by batch systems. The results showed that when the activated carbon was used separately to treat the high-salt organic wastewater, it achieved a highest COD removal rate of47.5%under the condition of activated carbon dosage of9.0g/L, adsorption time of60min and pH=6.0. Further more, the Fenton oxidation technology was used to treat the wastewater after activated carbon adsorption, and the COD removal rate can reach a highest value of84.4%under the condition of FeSO4·7H2O dosage of3.0g/L, H2O2dosage of20mL/L, reaction time of30min. Overall, after the treated by Activated carbon adsorption-Fenton oxidation, COD concentration decreased from the initial13650mg/L to560mg/L, and the removal rate reached95.9%. The activated carbon adsorption-Fenton oxidation process is suitable for the treatment of high-salt organic wastewater.When it comes to Fenton oxidation regeneration of activated carbon, the main research focus on FeSO1·7H2O dosage of H2O2plus the amount of initial pH, reaction time and the regeneration temperature on the rate of activated carbon regeneration. The results show that the per lOg saturated activated carbon dosing4.0gFeSO4·7H2O and20mLH2O2, initial pH3.0, reaction time is40min, and the regeneration temperature is40℃, the best activated carbon regeneration rate is100.5%, the adsorption effect of superior the original activated carbon, with high economic and practical value. Also, the use of Fenton oxidation regeneration of activated carbon process regeneration of activated carbon supplies costs about1800yuan/ton, far below the price of the original activated carbon, can further reduce the cost of activated carbon adsorption-Fenton oxidation of high concentrations of sulfate organic wastewater.