信号分子联合脱氮硫杆菌对同步脱氮除硫的影响

Effect of Signal Molecule Combined with Thiobacillus denitrificans on Simultaneous Removal of Nitrogen and Sulfur

为探究信号分子联合菌对同步脱氮除硫效果的影响,发现同时投加信号分子和脱氮硫杆菌可以加快硫化物和硝酸盐氮的去除且相比单独投加时更有利于单质硫的稳定积累和氮气产量的增加,并通过FISH技术检测了反应结束后微生物总量,信号联合脱氮硫杆菌可以增加微生物总数,因此能够实现较好地脱氮除硫效果.实验从不同信号分子浓度中找出了有利于单质硫稳定积累的最佳浓度,进而在此浓度下分析了单独投加信号分子、单独投加脱氮硫杆菌,以及同时投加信号分子和脱氮硫杆菌3种情况下的脱氮除硫效果.结果表明,当硫化物浓度为200mg·L^-1时,延长反应时间至72h后,信号分子联合脱氮硫杆菌使硫化物的去除率提高至99.8%,硝酸盐去除率提高至96.9%,且单质硫转化为硫酸盐的速率减慢,氮气的产量增加,反应结束后其单质硫和氮气的量分别达到59.0mg和80.0mL.当硫化物浓度为300mg·L^-1时,单独投加2.5μmol·L^-1的信号分子在72h时其硫化物和去除率达到99.0%,硝酸盐的去除达到93.9%,单质硫和氮气的产量分别达到63.1mg和79.5mL.

The effects of Thiobacillus denitrificans combined with signal molecules on the removal of sulfide and nitrate was investigated.By adding signal molecules and T.denitrificans at the same,the total number of microorganisms increased,the removal of sulfide and nitrate was accelerated,and an increase in nitrogen gas and more stable accumulation of elemental sulfur was observed.The total number of microorganisms after the reaction was detected using fluorescence in situ hybridization (FISH) technique.In this experiment,the optimal concentration for the stable accumulation of elemental sulfur from six concentrations of signal molecules was revealed.Further,the effects of adding signal molecules,T.denitrificans,and their combination were analyzed at this concentration. The results showed that it was easier to accumulate elemental sulfur after the addition of 1.0 μmol·L^-1 signal molecule.After adding both T.denitrificans and 1.0 μmol·L^-1 signal molecules at a sulfide concentration of 200 mg·L^-1,the removal of sulfide and nitrate increased to 99.8% and 96.9% at 72 h,respectively,and increases in nitrogen gas and sulfur were observed.The amounts of elemental sulfur and nitrogen gas reached to 59.0 mg and 80.0 mL,respectively,after adding 2.5 μmol·L^-1 signal molecules at 72 h when the sulfide concentration was 300 mg·L^-1.Under those conditions,the removal efficiency of sulfide and nitrate reached 99.0% and 93.9%,and the production of elemental sulfur and nitrogen reached 63.1 mg and 79.5 mL,respectively.