| With industrial development and acceleration of urbanization, amount of pollutants, especially organic compounds, were discharged into surface water in various ways. As a result, the pollution situation of water is more and more serious. However, drinking water quality standard has been upgraded constantly and people are setting more and more strict requirement for drinking water quality. Due to limitation of traditional process, treatment for micro-polluted water can't meet the current requirements for water quality any more. Advanced treatment was extremely urgent. The ozone and activated carbon technology has been recognized as the most effective and reliable technology which could be used to process polluted raw water, to reduce the concentration of organic matter in drinking water and the chlorination by-products. The general characteristics of Yellow River were obvious,such as high levels of ammonia nitrogen,serious micro-pollution, and so on. For the specific water quality characteristics of the section of Yellow River in Jinan, the full-scale experimental study was conducted in the Qingyuan Water Plant of Shanghe County where the post Ozone-Activated Carbon processing was adopted.The Qingyuan Water plant was designed by research Institute of Shandong Architectural University which was completed and put into operation in April 2009.The optimum process parameters were got in this study through system optimization analysis of post Ozone-Activated Carbon advanced treatment. The following four issues were discussed:selection of carbon species and determination of carbon layer thickness; the determination of ozone distribution ratio; the best dosage and contact time of ozone; the best time to activated carbon adsorption. (1)In the laboratory-scale experiment, three kinds of pillar activated carbon from coal of ZJ-15 were used. Through comprehensive comparison of their respective indices, including iodine value, the adsorption property with methylene blue, mechanical property, the adsorption rate of organic matter, adsorption content and adsorption isotherm. The result returns that 1 # activated carbon was better than 2 # and 3 # activated carbon, and 1 # activated carbon was used in the post ozone-activated carbon filter finally. Comparing indices of water turbidity, permanent value, ammonia nitrogen content, UV254 value of different carbon layer thickness, the result showed that the efficiency of activated carbon was relatively good and the height of carbon layer thickness was in a range of 160-200cm. Finally the height should be controlled in the range of 160-200cm.(2)Through investigation into the efficiency of activated carbon with four different ratios of ozone, it showed that their average removal efficiencies of turbidity, permanent value, ammonia nitrogen and UV254 were 20%,40.0%,74.8% and 79.2% respectively while the dosing ratio of ozone was 1:2.Taking the operation stability into account,the dosing ratio of ozone should be set at 1:2.(3) While the dosage of ozone was 1.8mg/L, it has the best removal efficiency of organic matter in the activated carbon filter. While the the dosage of ozone was in a range of 1.8-2.Omg/L,the ammonia nitrogen was well removed. It was found that the best ozone contact time was between 11～13min by analyzing the permanganate value and UV254 value of filtered water with different ozone contact time. Based on water features, the best Ozone dosage was controlled at 1.8mg/L and the best contact time was 11min.(4) Through analysis of effects on turbidity,ammonia nitrogen, organic matter in different activated carbon adsorption time, it is determined that under current conditions the best contact time for activated carbon filter is 14min,.The process parameters of post advanced treatment were improved in this study to direct the practical operations of Qingyuan Water Plant,as well as to offer correlation operation parameters for design and operation of Ozone-Activated Carbon advanced treatment plant.
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