| Currently, with the rapid economic growth and accelerating urbanization construction, MSW (Municipal Solid Waste) pollution has become unneglected problem which can be an obstacle to urban development and influence the sustainable development strategy. The aerobic composting technology is a recycling and harmless way in the municipal solid waste treatment. However, the environmental scientists pay more and more attention to the compost odour which make people uncomfortable. The biofiltration deal with the odour is more superior than other traditional.In this work,the biofilter packed with the compost were employed to remove low concentration ammonia gas with the long-term study.Investigated in different conditions,the reactor ammonia removal efficiency, also investigated the conversion of ammonia.And make a research on the biofilter purification of municipal solid waste composting oduor. Finally, by the results of previous studies, the biological filter reactor ammonia removal mechanism was discussed preliminarily.The following conclusions were obtained from the experiment:(1) The biological filter reactor can effectively remove ammonia, the reactor starts quickly, just 10 days, the removal efficiency of NH3 exceed 95% steadily, the outlet ammonia concentration can meet the national emission standards and the system has the steady capability for more than 95% removal efficiency (inlet concentration is 100-500mg/m3);When the inlet load at 6-72g·m-3·h-1,the ammonia removal load between 6-72g·m-3·h-1, the ammonia reactor removal capacity of the maximum load in the reactor has not been received. Thus, when raise the inlet load, the reactor also has a higher potential of the ammonia removal capabilities.(2) The pH of compost packing is between 5.8-8.5. No acidification occurs, which is be beneficial to the long-term stable operation of biological filter reactor. As the reaction to, NH4+-N were significantly reduced, while the NO2--N,NO3--N content increased significantly. The results showed that the nitrification reaction happens and make the first place, microorganisms transform lots of NH4+-N into NO2--N,and NO3--N。(3) In the high-temperature aerobic composting process, ammonia is produced with the composting process, generally shows irregular parabola, and reaches maximum concentration in the maximum temperature of compost. NH3 and NH4+-N concentration in the process of consistent and mutually influence each other. Meanwhile, NH4+-N concentration also affected the TN concentration, but the high temperature phase in composting, there is no nitrification,the two concentration almost identical. The change of ammonia concentration also decide the pH.In the municipal solid waste aerobic composting process, ammonia concentration is between 100-500mg/m3. Biological filter reactor has about 98% removal efficiency of NH3. From that we see it is feasible to remove the ammonia produced composting by using the biological filter reactor.(4) According to the principle of biological purification of gas and double-membrane theory, we obtain the ammonia removal is the interaction result of physical, chemical, biological reactions. Purification process can be divided into mass transfer and biodegradation process. It is generally believed that NH3 biochemical degradation process as follows:NH3(g)→NH4(OH)→NO2-→NO3-。...
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