Research On The Treatment Of The Yellow River Micro-polluted Water In Shanxi By Ozone-activated Carbon Process

Affected by the pollution of the industrial and mining enterprises and hydro-climatic conditions, the water of a reservoir filling with Yellow River water in Shanxi is micro-polluted, which also has a risk of petroleum substances or pHenol exceeding seasonally. The conventional treatment process is difficult to guarantee the effluent quality. Therefore, the research on optimizing activated carbon, the parameter optimization of activated carbon filter and ozone oxidation process, and the efficiencies of special pollutions for ozone-actived carbon process were investigated in this study.Comparing the iodine value, methylene blue value, adsorption rate, adsorption capacity and isothermal adsorption curve, the optical order can be concluded initially:3#carbon>2#carbon>4#carbon>1#carbon. And the pilot-scale results showed that3#carbon was the optical one, followed by2#carbon with the1#carbon was the worst.The study of optimization about operating parameters for active carbon filter showed that: the pollutants removal efficiencies of active carbon filter improved continuously with the extension of carbon filter residential time, when the carbon filter residential time was less than15min. And the removal efficiency achieved a plateau when the residential time was above15min. The removals of UV254、CODMn and NH4+-N improved initially, then stabilized with the increasing of carbon layer thickness, and the minimum carbon layer thickness was90cm,70cm,90cm respectively. The pollutions concentrations of the effluent were high at the beginning of filter process, and then dropped constantly until reached stabilization with the extension of filtration time. So process time of the initial filter water should more than30min. The longest filtration cycle for UV254、CODMn and NH4+-N were7-8days,7-8days, and8-10days. Plan four was the best one for high-speed water backwash, and for gas-water combined backwash, plan four and five was the optimization. Besides, the gas-water combined backwash was better than high-speed water backwash.The optimization of operating parameters for active carbon filter showed below: the two levels of ozone dosage method is superior to the single-stage, and1:1was the best dosage ratio. Under the best dosage method and ratio condition, the optimal dosages were2.0-2.5mg/L,2.0mg/L,2.0mg/L,2.0-2.5mg/L. Moreover, the effluent concentrations of them were below100CNT/ml,0.0069cm-1,0.81mg/L,0.031mg/L.The results of the research on the removals of special pollutants by ozone-actived carbon process showed that: By legitimately optimizing the ozone dosage, the concentrations of the bromate and formaldehyde could be controlled below5.2ug/L and20ug/L respectively. The removal efficiencies of THMFP and HAAFP were visible, and the removal of each was30.58%,58.95%. The concentration of AOC improved after ozonation. The removal of AOC was69.13%, with the effluent concentration of31.36ug/L. When the concentrations of the CODMn or NH4+-N were higher than the standard, the removals of them were69.13%,91.67%with each dosage of2.3mg/L,2.5mg/L, respectively. Besides, when the concentration of petroleum substances or pHenol was higher than the standard, the removals and effluent concentration of each were79.31%,88.16%and both below0.05mg/L,0.002mg/L at each optimal dosage of2.3mg/L and2.5mg/L respectively.