Wang Wei, Jiang Hongyan, Zhu Guangquan, Song Xueying, Liu Xingyu, Qiao Ya
Key Laboratory of Pollution Processes and Environmental Criteria of Ministry of Education, Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin, 300071, China.
Environ Sci Pollut Res Int. 2016 Mar;23(5):4868-75. doi: 10.1007/s11356-015-5723-9. Epub 2015 Nov 6.
To improve the denitrification characteristics of anaerobic denitrifying bacteria and obviate the disadvantage of use of explosive hydrogen gas, tourmaline, a polar mineral, was added to the hydrogenotrophic denitrification system in this study. Microbial reduction of nitrate in the presence of tourmaline was evaluated to assess the promotion effect of tourmaline on nitrate biodegradation. The experiment results demonstrated that tourmaline speeded up the cultivation process of bacteria from 65 to 36 days. After domestication of the bacteria, nitrate (50 mg NO3 (-)-N L(-1)) was completely removed within 3 days in the combined tourmaline-bacteria system, and the generated nitrite was also removed within 8 days. The reduction rate in this system is higher relative to that in the bacteria system alone. Efficient removal of nitrate by tourmaline-supported anaerobic bacteria (without external hydrogen input) indicated that tourmaline might act as the sole hydrogen donor to sustain autotrophic denitrification. Besides the production of hydrogen, the promoted activity of anaerobic denitrifying bacteria might be caused by the change of water properties, e.g., the pH of aqueous solutions was altered to about 8.0 and the oxidation-reduction potential decreased by 62 % in the tourmaline system. The distinctive effects of tourmaline on bacteria were related to its electric properties.
为了改善厌氧反硝化细菌的反硝化特性并消除使用易爆氢气的缺点，本研究将电气石这种极性矿物添加到氢营养型反硝化系统中。评估了在电气石存在下微生物对硝酸盐的还原作用，以评估电气石对硝酸盐生物降解的促进作用。实验结果表明，电气石将细菌的培养过程从65天缩短至36天。细菌驯化后，在电气石 - 细菌联合系统中，硝酸盐（50 mg NO3 (-)-N L(-1)）在3天内被完全去除，产生的亚硝酸盐也在8天内被去除。该系统的还原率相对于单独的细菌系统更高。电气石负载的厌氧细菌（无需外部氢气输入）对硝酸盐的高效去除表明，电气石可能作为唯一的氢供体来维持自养反硝化。除了产生氢气外，厌氧反硝化细菌活性的提高可能是由水性质的变化引起的，例如，在电气石系统中，水溶液的pH值变为约8.0，氧化还原电位降低了62%。电气石对细菌的独特作用与其电学性质有关。
