Study on the diversity of denitrification bacteria treating with wastewater by using PPGC filler on SBMBBR at low temperature

Abstract

Aiming at the problem of the low removal efficiency of biological nitrogen-removing of low temperature waste-water, using Polyurethane Porous Gel Carrier (PPGC)-SBMBBR treated low temperature sewage, in compared with conventional SBR,and viaing Miseq high-throughput sequencing technology in analysis of the differences of microbial diversity and abundance of structure on the two reactors of activated sludge, revealed dominant nitrogen-removing bacterium improving the treatment efficiency of low temperature sewage. The results shows that the removal efficiency of the effluent nitrogen and the sludge sedimentation rate of (PPGC)-SBMBBR reactor are significantly improved under the water temperature (6.5±1℃). Adding the filler can contribute to improvement of bacterial diversity and relative abundance of nitrification and denitrification bacterium in the activated sludge system. The main relative abundance of ammonia oxidizing bacteria (AOB),nitrite oxidizing bacteria (NOB),anaerobic denitrifying bacteria, and aerobic denitrifying bacteria in (PPGC)-SBMBBR(R2) are significantly better than SBR (R1),and the R2 reactor can independently enrich the nitrifying bacteria and the aerobic denitrifying bacteria, such as Nitrospira, Hydrogens, Pseudomonas, and Zoogloea. The total relative abundance of dominant and nitrifying denitrifying bacterium increases from 28.65% of R1 to 60.23% of R2, providing a microbiological reference for improving the efficiency of biological nitrogen removal in low temperature waste-water.