| Due to dry weather conditions which in rural Northwest China, water scarcity, only to solve the drinking water problem by collecting rainwater into the cel ar, but due to the limitation of rainwater harvesting conditions, drinking water safety can not be guaranteed, so that the pit water are subject to different degrees of pollution and transformed into micro-polluted water on people’s health hazard. This requires us to seek an urgent need to be able to apply for decentralized rural water supply water treatment technology to solve the problem of rural drinking water safety.Slow biological treatment process technology because of simple structure, easy operation and management, easy miniaturization and low cost is widely used, while its turbidity, ammonia, viruses and bacteria have a good removal efficiency, it can be applied Rural smal, decentralized water supply.This paper aims to study biological slow filtration treatment process and characteristics of the role of microorganisms in seeking different ways to make the treatment effect is more secure and reliable. The first is on the start slow biological filter and the conventional way of natural biofilm inoculum with a new way of biofilm compared to investigate the removal of pollutants; Secondly, the growth of microorganisms during biofilm analyzed Learn the rules of the microbial growth and biofilm removal of ammonia nitrogen microbiological mechanism; then by the biofilm analyze and study the distribution of biomass and influencing factors, and to explore the characteristics of biofilms and biofilm activity Biological phase analysis; and final y the slow increase biological filter to remove ammonia nitrogen to prevent decline after the collapse of ammonia and other denitrifying bacteria degradation efficiency by bacterial biofilms on nitrification were isolated, cultured and explore the removal of ammonia nitrogen.In biofilm start trials, respectively 1# and 2# filter filter column column natural biofilm and inoculation biofilm, through the study found 14 days 2# filter column biofilm successful than the advance 1# filter column, 2# filter column of turbidity, ammonia, CODMn mean removal were 89.27%, 48.89% and 90.08%, 1# filter column corresponding mean removal were 88.54%, 42.17% and 86.79%, that vaccination can reduce biofilm hang film cycles, increase turbidity, ammonia, CODMn removal. Microbial growth, the discovery phase of biofilm microbial growth and various flora and play a role to stabilize the removal of organic matter is not the same time, heterotrophic ammonia oxidizing bacteria faster than about 5 days, ammonia-oxidizing bacteria than nitrite salt oxidizing bacteria for nearly 10 days, the fastest growth of heterotrophic bacteria, followed by ammonia oxidizing bacteria, nitrite-oxidizing bacteria slowest. Biofilm characteristics of the study, found that the biomass at the surface of filter 2# filter column stable to 54 nmol P/g, SOUR mean of 0.14mgO2/(g?h) about uptime 105 days or so, 1# filter Biomass column stable at the surface of the filter is 46 nmol P/g, SOUR mean 0.18 mg O2/(g?h) around the stable operation of about 120 days that inoculation biofilm biomass is general y higher than the natural biofilm, but stable inoculation biofilm activity below the natural biofilm and microbial easy to decline, stable operation of the filter column to reduce the time; and in the longitudinal distribution media, apparatus from top to bottom water, biomass distribution gradually from top to bottom reduce, filter carrier biofilm activity from top to bottom before final y raised high, then low. Separation of the nitrifying bacteria in biofilms to optimize the separation process, the final success of the nitrifying bacteria biofilm were separated, and the denitrifying bacteria inoculated into the water after separation and purification, found that the removal of ammonia nitrogen only 3 days can reach 90%. |
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