Liu Xiaohui, Wei Jia, Wu Yaodong, Zhang Jing, Xing Luyi, Zhang Yifei, Pan Guoping, Li Jiamei, Xu Mengdie, Li Jun
College of Architecture Engineering, Beijing University of Technology, 100 Pingleyuan, Chaoyang District, Beijing 100124, China.
College of Architecture Engineering, Beijing University of Technology, 100 Pingleyuan, Chaoyang District, Beijing 100124, China.
Bioresour Technol. 2022 Feb;345:126523. doi: 10.1016/j.biortech.2021.126523. Epub 2021 Dec 9.
Immobilized microorganism technology has attracted increasing attention for high concentration of microbes, low cell loss and high resistance to impact of environment. The microbial reduction of nitrate in the presence of sediment-based biochar (SBC) and nanoscale zero-valent iron (nZVI) was investigated in four different free systems. NZVI-SBC/bacteria system realized the best nitrate removal of 97.61% within 3 days through the synergistic effect of SBC and nZVI on denitrifying bacteria. Accumulation of nitrite and ammonium in nZVI-SBC/bacteria system also decreased. High-throughput sequencing results showed that the proportion of denitrifying bacteria in microbial community structure increased after adding nZVI-SBC. The performance of nitrate removal was then studied through PVA/SA-immobilization. Immobilized active pellets performed better nitrate removal (98.89%) and stronger tolerance under different conditions than the free bacterial cells. Overall, this study provided a promising approach by utilizing SBC and nZVI for the bio-remediation of nitrate-contaminated water in practical application.
固定化微生物技术因其微生物浓度高、细胞损失低和对环境冲击的高抗性而受到越来越多的关注。在四种不同的游离体系中研究了基于沉积物的生物炭（SBC）和纳米零价铁（nZVI）存在下微生物对硝酸盐的还原作用。NZVI-SBC/细菌体系通过SBC和nZVI对反硝化细菌的协同作用，在3天内实现了最佳的硝酸盐去除率，达到97.61%。nZVI-SBC/细菌体系中亚硝酸盐和铵的积累也有所减少。高通量测序结果表明，添加nZVI-SBC后，微生物群落结构中反硝化细菌的比例增加。然后通过聚乙烯醇/海藻酸钠固定化研究了硝酸盐去除性能。固定化活性颗粒在不同条件下比游离细菌细胞表现出更好的硝酸盐去除效果（98.89%）和更强的耐受性。总体而言，本研究提供了一种在实际应用中利用SBC和nZVI对硝酸盐污染水进行生物修复的有前景的方法。
