Experimental Research On Fine Bubble Aeration And Biofilm Treatment Of Rural Sewage

China is a developing country, which is facing lots of serious environmental problems, especially water environment. At present, the government pays more attention to cities than to rural aeras on environmental protection. As we all know, China is a large agricultural country, the water pollution of small rivers in rural aeras have become increasingly prominent. Statistics show that the main sources of rural river are:fertilizers and pesticides, livestock manure, enterprises sewage and domestic sewage.In this review, the researsh progress of biofilm,common carriers and applications are introduced,while the study and application of Aquamats are briefly introduced.Besides,some research and application examples of fine pore aeration is given, and the current research focus is pointed out. Besides, based on the domestic and foreign research, the effect of aeration rate, installation depth, superficial area, pore diameter, water quality and pore clogging on oxygenation performance is summarized as well as the shortage of current research. It is expected to provide useful information for the wastewater treatment plants to optimize the aeration systems, and for the researchers who will take fine pore aeration as a ecological restoration technique.For Aeration rate, pore diameter and depth have a significant influence on the performance of fine pore aeration.It is necessary for improving the oxygenation performance to study the relationship between these three parameters.In this paper,the results have been tested that different aeration rates(0.5m3/h, 1m3/h,1.5m3/h,2m3/h,2.5m3/h,3m3/h), aperture(50μm, 100μm,200μm,500μm) and depth(0.8m,1.1m,1.3m,1.5m,1.8m, 2.0m) affecting on volumetric mass transfer coefficient, standard oxygen transfer efficiency and standard aeration efficiency.Besides,the most appropriate parameters have been optimized through these curves.The results showed that the best oxygenation performance is 200μm aperture with 0.5m3/h aeration rate in 2.0m depth water.In the practical productions and applications, the approach of intermittent aeration is usually used in the aeration process.In this paper, continuous aeration and different intermittent aeration(aeration on/off time ratio are 1h-1h、2h-1h、2h-2h、2h-3h、3h-2h)were studied in removal rate of CODMn、NH3-N、TN、TP. The results showed thatthe condition of aeration on/off time ratio of 2h:2h is the best way, considering the removal rate of organic matter, nitrogen and phosphorus.Biofilm is now widely used in sewage treatment technology. The carriersare the core of biofilm, which have a direct impact on the effect of sewage treatment. In this paper,as microorganism carriers, fiber ball packing, combination packing and Aquamats are used to reduce the revomal rate of CODMn, total nitrogen, total phosphorus and ammonia ofrural sewage. Besides, The removal rate of CODMn, total nitrogen, total phosphorus and ammonia influenced by different hydraulic retention times (24h,12h,6h) are studied.The results show that thefiber ball packing is better than combination packing and Aquamats as biofilm carrier has better adsorption of sludge and removal rate of contaminants, the influence of HRT on and NH3-N is obvious. The results show that the longer HRT, the higher removal rate.