School of Civil Engineering, Wuhan University, Wuhan 430072, China.
School of Civil Engineering, Wuhan University, Wuhan 430072, China.
Sci Total Environ. 2019 Dec 1;694:133775. doi: 10.1016/j.scitotenv.2019.133775. Epub 2019 Aug 5.
The lab-scale system combined bioelectrochemical and sulfur autotrophic denitrification (CBSAD) was established to evaluate the effects of currents (50-300 mA) on both the performances and microbial communities. Results showed that the nitrate removal rate increased significantly when the current increased from 50 to 200 mA, while it slightly decreased with higher currents. Mass balance results revealed that hydrogen autotrophic denitrification contributed almost three times (70.25-78.62%) to denitrification compared with that of the sulfur part (21.38-29.75%). Illumina MiSeq sequencing showed that the currents changed the bacterial richness and diversity in this system. Phylum Firmicutes and class Clostridia predominated >50% under each condition. And multiple key bacteria capable of denitrification such as Proteiniclasticum, Thauera and Family_XI_uncultured were identified and found in higher proportions when the current was 200 mA. Therefore, this study helps revealing the mechanisms of accelerating nitrate-reduction through applied currents in the CBSAD systems.
实验室规模的系统结合生物电化学和硫自养反硝化（CBSAD），以评估电流（50-300 mA）对性能和微生物群落的影响。结果表明，当电流从 50 mA 增加到 200 mA 时，硝酸盐去除率显著提高，而当电流增加到更高时，去除率略有下降。质量平衡结果表明，与硫部分（21.38-29.75%）相比，氢自养反硝化对反硝化的贡献几乎高出三倍（70.25-78.62%）。Illumina MiSeq 测序表明，电流改变了系统中的细菌丰富度和多样性。在每种条件下，厚壁菌门和梭菌纲都占主导地位，超过 50%。并且当电流为 200 mA 时，发现了多种能够进行反硝化作用的关键细菌，如蛋白菌属、陶厄氏菌属和未培养的 X 科菌属，它们的比例更高。因此，本研究有助于揭示在 CBSAD 系统中通过施加电流来加速硝酸盐还原的机制。
