Abstract:Owing to the characteristics of high nitrogen content and low carbon sources, the treatment of traditional activated sludge is not satisfactory, such as the reaction of ammonia nitrogen. Therefore, combining the two method, the system of the zero-valence iron and the microbial coupling system is formed. In this paper, based on the experiment, studies the zero-valent iron and characteristics of the microbial nitrogen coupling system and the influence factors of system efficiency of denitrification, and analyzed by scanning electron microscopy(sem)is zero-valent iron and the mechanism of microbial nitrogen coupling system. The result shows that the iron planer and the microbial coupling system are more efficient in denitrification when the initial total nitrogen concentration is 15 mg/L. Pickling can increase the surface reaction area of the zero-valence iron and improve the efficiency of denitrification. The optimum dosage of iron planer is 15 g/L, the optimum water retention time for the iron and microbial coupling system is 12 h, the optimum pH for the coupling system ranges from 6. 0 to 7. 5, and the best temperature is about 35 ℃ for coupled system denitrification.