| Enhanced Primary Treatment, compared with biological treatment, is excellent in reducing more pollutants with lower cost. This feature makes it be especially suitable for developing countries which have faster development and heavier contaminations. In recent years, enhanced primary treatment has been a very hot research spot in the wastewater treatment fields in and abroad the country. And along with more and more new, highly effective and inexpensive flocculants'appearance, it will receive worldwide value and appliance。Pneumatic flocculation is a special kind of flocculation process which has its own characters and advantages in municipal wastewater treatment. It can not only be able to enhance the removal rate of the colloids and the suspended substances but also increase the dissolved oxygen in wastewater. In recent years, there're few of the research paying attention on it, so the optimized parameters which are existed are different a lot. Since the theoretical research has not been completed, there're no uniform control parameters of pneumatic flocculation, which makes many disadvantages in using and researching it. Therefore, the aim of my research is first to check the viability of pneumatic flocculation, to optimize the optimum dosage of the pneumatic flocculation and the optimum air loading, to verify the mathematical model of the pneumatic flocculation, and then to evaluate the efficiency of the pollutants removal rate and the modified mathematic model. According to my research, both the theoretical modal and the experimental parameters can be basically used in practice.According to the experiment research, there're 4 indicators have been decided. They're the optimized dosage of PFAC and PAM which is detected as 150mg/L and 0.5mg/L, the optimized dosing order is inorganic first, the optimized air flow rate is 0.5 m3(air)/m3(water), the optimized aeration intensity(between 31.4×10-3cc/cc.min～74.1×10-3cc/cc.min) is always higher than 58.1×10-3cc/cc.min and the optimized reaction time is lower than 9min. Based on these optimized parameters, the other kind of wastewater had been used to compare the removal effect of the pollutants. It is demonstrated that pneumatic flocculation is more suitable in dealing with municipal wastewater. And the effect of the removal rate of TP is higher when it's compared with the removal rate of TN. Finally, the effect of the increase in the amount of DO is remarkable which is an obviously character compared with mechanical and hydraulic flocculation.Meanwhile, further analyses had been made to improve the kinetics theory. As a special kind of flocculation and agitation process, three-phase inter-reaction of gas-liquid solid certainly exists. The form and break of the flocs are closely related to it. And it is certain to have direct affect on removal rate of the pollutants. And then, account for the dual role of the bubbles created in flocculation process, it is accepted that aeration intensity is a suitable control parameter in pneumatic flocculation. According to analyzing the existed problems of S.K equation, there're some conclusions have come up. The linearity relationship between the pollutants removal rate and the aeration intensity has been affirmed, which forms a primary equation: R——percentage removal rate of the pollutants; q——aeration intensity,cc/(cc.min); K′——slope,closely to the wastewater quality and in this research is 7.9; K 1——intercept,closely to the wastewater quality and sedimentation time,when the sedimentation time is 30min,60min,90min, K 1 is respectively as -0.16,-0.12,-0.08; This equation can play a significant role and important guidance in measuring the parameters of the pneumatic flocculation, and make an open eye to the further research.This subject has been deeply researched on the pneumatic flocculation in experimental and theoretical aspects. Further research has been done to the kinetic mechanism, which can enrich the basic theory of the pneumatic flocculation. At the same time, related parameters have been optimized. All of these have made certain contributions to the pneumatic flocculation's application in enhanced primary treatment for wastewater.
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