R2+esearch Of Hg²⁺’s Effect On Aerobic Denitrification

As the deeper research of aerobic denitrifying bacteria, whose potential applied on thebiological filtration system is more and more obvious, one of the typical applications isdenitrification in coal-fired power plant. Comparing with conventional methods such asselective catalytic reduction, biological filtration using aerobic denitrifying bacteria to removenitrogen shows its advantages of low cost, short residence time and no secondary pollution, soit is of development prospect. However, the flue gas from desulfurization tower dosen’t onlycontain oxygen and nitrogen oxides, but also heavy metals, especially for mercury, which is ahighly toxic substance and of most content, in addition, whether it has an effect on nitrogenremoval of aerobic denitrifying bacteria and interaction between them is worth exploring.In the paper, the screened strain was aerobic heterotrophic denitrifying bacteria. Firstly,implemented domestication and purification for bacterium resistence to mercury, andexplored the characteristics of its resistance to mercury. Then an aerobic denitrificationbio-filter system was established, Hg²⁺’s effect on reactor’s membrane hanging underaerobic environment was studied; In normal operation process, Hg²⁺’s effect on aerobicdenitrification and its own change by successively changing factors such as wastewater’scarbon source, C/N ratio, initial NH₄⁺-N concentration, hydraulic retention time （HRT）, theratio of air to water and so on was studied to get the best operation parameters, which couldprovide certain theoretical basis for industrial removal of nitrogen and mercury. Resultsshowed that the mercury resistant strain belonged to Pseudomonas putida throughtechnologies of molecular sequencing and phylogenetic tree’s construction; judged the mainmechanism of pseudomonas putida’s resistant to mercury was cell wall adsorption andintracellular accumulation by infrared spectroscopy and scanning electron microscopeanalysis.