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The swine wastewater become an important source of pollution of the environment. Swine wastewater containing high concentrations of organic matter and SS as well as organic nitrogen. For swine wastewater characteristics, most take biological nitrogen removal process for processing. Traditional biological nitrogen removal through autotrophic nitrifying bacteria completed swine wastewater containing high concentrations of organic matter will inhibit autotrophic nitrifying bacteria, nitrification, denitrification effect bad. Screened from swine wastewater treatment pond sludge in a high concentration of organic matter still has strong denitrification capacity in addition to carbon heterotrophic nitrifying bacteria and small test experiment investigated swine wastewater processing effect. The results showed that: 1, pig farm wastewater treatment activated sludge separation, enrichment culture isolated four heterotrophic nitrifying bacteria, and observed a sieve to strain the colony morphology and cell morphology. PCR molecular biology techniques and Biolog Microbial analyzer identification of strains at the same time, four bacteria Alcaligenes faecalis. 2, in a laboratory pure culture conditions, were investigated four bacteria denitrification capability. Show that the four strains with nitrification and denitrification, but the ability to vary; ammonia nitrogen and total nitrogen content in the medium 48h before a sharp decline in the 48 hours after stabilized. Strains 79,84, L116, L117 after 48 h treatment, ammonia degradation rate were 44.42%, 47.87%, 61.29% and 56.38% of the total nitrogen (sterilization) removal rates reached 39.92%, 38.52%, 43.37% and 40.74%. Laboratory three heterotrophic nitrification bacteria, and the the sieve four Alcaligenes faecalis optimization heterotrophic nitrification combined into a composite bacteria, and in accordance with the the orthogonal pilot program to establish SBR reactor, investigated composite heterotrophic denitrifying bacteria in different residence time, influent concentration and inoculum size conditions under of swine wastewater denitrification capacity. Acclimation period, ammonia nitrogen, total nitrogen and COD content of each reactor has decreased, but different degradation rates; stable operation period, the reactor effluent ammonia nitrogen, total nitrogen and COD concentration has stabilized. Comprehensive experimental results, the reactor 1, hydraulic retention time of 60 days, the influent best nitrate removal carbon effect of 1% for Swine wastewater was diluted 10 times and inoculation. 4, the use of Biolog-ECO method and means of PCR-DGGE molecular explore the reactor microbial community diversity and its differences. Analysis of Shannon, Simpson and McIntosh index shows that rich microbial community in the reactor, and the richness of the microbial community, common species and species homogeneity were different, but the difference was not obvious. And each reactor for the comprehensive utilization of six types of carbon sources. In addition, PCR-DGGE experiments found that each reactor the same microbial populations also have their own specialty populations, and the richness of the microbial community is different. Rich dominant microbial populations in the 9th reactor, the reactor of at least 6.
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