Factors Affecting the Simultaneous Removal of Nitrate and Reactive Black 5 Dye via Hydrogen-Based Denitrification
Factors Affecting the Simultaneous Removal of Nitrate and Reactive Black 5 Dye via Hydrogen-Based Denitrification
复制标题
DOI：
10.3390/w13070922
复制
发表时间：
2021-03
期刊：
影响因子：
3.4
通讯作者：
T. Singhopon;Kenta Shinoda;Suphatchai Rujakom;F. Kazama
中科院分区：
文献类型：
--
作者：
T. Singhopon;Kenta Shinoda;Suphatchai Rujakom;F. Kazama
纺织废水（TW）含有有毒污染物，对环境和人类健康构成风险。据报道，其中一些污染物，包括NO3-、NO2-和活性黑5（RB-5）染料，可以通过氢基反硝化（HD）去除;然而，目前还不清楚不同的因素如何影响它们的同时去除。本研究旨在探讨氢气流量、空气和氢气的鼓泡周期以及染料初始浓度对TW处理过程的影响。因此，两个反应器，一个厌氧HD反应器和一个组合的好氧/厌氧HD反应器，被用来研究处理性能。结果表明，增加厌氧HD反应器中H2流量，可提高脱氮和脱色去除率。此外，增加厌氧处理的时间显着提高了复合反应器中的污染物去除率。此外，初始染料浓度的增加导致较低的氮去除率。此外，一些染料在HD过程中通过细菌降解而脱色，并且增加初始染料浓度导致脱色率降低。细菌群落，包括黄单胞菌科、红环菌科和Thauera属，的微生物物种，发挥了关键作用的脱氮和RB-5脱色的机制，在两个HD条件下。然而，这两个反应器表现出类似的处理效率，因此，基于这些结果，应使用一个组合的好氧/厌氧HD系统，以减少有机/无机污染物的含量在真实的纺织废水排放前建议。
Textile wastewater (TW) contains toxic pollutants that pose both environmental and human health risks. Reportedly, some of these pollutants, including NO3−, NO2− and reactive black 5 (RB-5) dye, can be removed via hydrogen-based denitrification (HD); however, it is still unclear how different factors affect their simultaneous removal. This study aimed to investigate the effect of H2 flow rate, the sparging cycle of air and H2, and initial dye concentration on the TW treatment process. Thus, two reactors, an anaerobic HD reactor and a combined aerobic/anaerobic HD reactor, were used to investigate the treatment performance. The results obtained that increasing the H2 flow rate in the anaerobic HD reactor increased nitrogen removal and decolorization removal rates. Further, increasing the time for anaerobic treatment significantly enhanced the pollutant removal rate in the combined reactor. Furthermore, an increase in initial dye concentration resulted in lower nitrogen removal rates. Additionally, some of the dye was decolorized during the HD process via bacterial degradation, and increasing the initial dye concentration resulted in a decrease in the decolorization rate. Bacterial communities, including Xanthomonadaceae, Rhodocyclaceae, and Thauera spp., are presented as the microbial species that play a key role in the mechanisms related to nitrogen removal and RB-5 decolorization under both HD conditions. However, both reactors showed similar treatment efficiencies; hence, based on these results, the use of a combined aerobic/anaerobic HD system should be used to reduce organic/inorganic pollutant contents in real textile wastewater before discharging is recommended.