The Experimental Study On Thiobacillus Denitrificans Remove The Nitrate Nitrogen In Groundwater

In order to study the Thiobacillus Denitrificans nitrate nitrogen removalcharacteristics and find out the best sulfur source,take a series of experiments,try toremove sulfate ions generated by the reaction in the bacteria use the sulfur sourcefor denitrification process at the same time.The autotrophic denitrification bacteriawas concentrated and separated from three different soil,select one strain with thehighest denitrification metabolic capacity to other experiments. Based on theanalysis of physiological and biochemical measurements, this stain was identifiedwith Thiobacillus denitrificans.Comparison the efficiency of nitrogen removal anddenitrification in the presence of pyrite,thiosulfate and brimstone to determine thebest sulfur source.Through a series of initial nitrate nitrogen concentrationexperiment to prove that the stain have a high denitrification capacity when the bestsulfue source was adding in themedium.Try to use the sulfur source/limestonecombination of methods and add a certain amount of limestone in the medium ofpyrite as a sulfur source,and to observe the presence of sulfate in the bacteria. Theexperiments showed that the highest removal efficiency of nitrate nitrogen is in thepresence of pyrite, the rate can reach79.49%.In a series of initial concentration ofnitrate nitrogen, bacteria can use pyrite to denitrification and the nitrate nitrogenremoval rate can reach a higher level. When the medium initial nitrate nitrogenconcentration was200mg/L, the removal efficiency take the highest rate as82.25%.In the medium with pyrite/limestonem,the removal efficiency of nitrogennitrogen can reach76.33%,description that the limestone almost does not affect thedenitrification metabolic capacity.And at the same time,the strains can effectivelyremove the sulfate and it was always controlled at a lower level. Through a seriesof initial nitrate nitrogen concentration experiment to prove that the stain have ahigh denitrification capacity when pyrite/limestonem was adding in the medium.And when the initial nitrate nitrogen concentration was200mg/L, the removalefficiency take the highest rate as78.53%.And the Sulfate concentrations can becontrolled at a lower level,the sulfate concentration was always be able to reach thegroundwater environment two quality standards, eventually reach the purpose ofremove nitrates without adding in the sulfate as new pollution.