生物炭及其碳骨架对微生物去除水中低浓度硝酸盐的影响  

Effects of Biochar and Its Skeleton on the Removal of Low Concentration Nitrate in Water by Denitrifiers

作　　者：常智淋 王朝旭[1,2] 张峰 李红艳[1,2] 崔建国 CHANG Zhi-lin;WANG Chao-xu;ZHANG Feng;LI Hong-yan;CUI Jian-guo(College of Environmental Science and Engineering,Taiyuan University of Technology,Jinzhong 030600,China;Innovation Center for Postgraduate Edu-cation in Municipal Engineering of Shanxi Province,Jinzhong 030600,China)

机构地区：[1]太原理工大学环境科学与工程学院,山西晋中030600 [2]山西省市政工程研究生教育创新中心,山西晋中030600

出　　处：《生态与农村环境学报》2022年第11期1464-1472,共9页Journal of Ecology and Rural Environment

基　　金：山西省自然科学基金(201901D111066)。

摘　　要：为探究生物炭及其碳骨架对反硝化过程及N_(2)O排放的影响,以稻壳生物炭(BC)为例,通过水洗法制备碳骨架(WBC)和浸提液(BCE),并富集筛选厌氧反硝化细菌(DB),然后分别在BC、WBC或BCE存在条件下,开展DB去除模拟废水中低浓度硝酸盐(约10 mg·L^(-1))的室内培养试验,探究培养过程中模拟废水N_(2)O和N_(2)O+N_(2)排放速率、理化指标及硝酸盐还原酶和亚硝酸盐还原酶活性的动态变化。结果表明,模拟废水N_(2)O排放完全通过微生物途径产生。DB处理反硝化速率(N_(2)O+N_(2)排放速率)峰值(以N计)在培养48 h时出现,而DB+BC处理反硝化速率峰值在36 h时出现,DB+WBC处理反硝化速率峰值甚至在24 h时出现,且DB+BC和DB+WBC处理峰值(分别为44087.79和46826.27 ng·h^(-1))均明显高于DB处理(38097.45 ng·h^(-1))。与DB处理相比,DB+BC和DB+WBC处理N_(2)O+N_(2)累积排放量分别增加30.17%和2.86%,N_(2)O累积排放量分别减少83.04%和74.52%,表明生物炭及其碳骨架均能提高反硝化速率,并促进N_(2)O还原。与DB+BC处理相比,DB+WBC处理N_(2)O+N_(2)累积排放量减少20.98%,表明碳骨架的反硝化促进作用不及生物炭,但碳骨架的电导结构在反硝化过程中仍起主要作用。The purpose of the study is to investigate the effects of rice husk⁃derived biochar and its skeleton on denitrifica⁃tion and N_(2)O emission.Based on the preparation of biochar skeleton(WBC)and the extract of biochar(BCE)by water⁃washing method and the enrichment and screening of an anaerobic denitrifier(DB),the microcosm incubation experiment was carried out to explore the removal efficiency of low concentration nitrate(about 10 mg·L^(-1))in simulated wastewater by DB.N_(2)O and N_(2)O+N_(2)emission rates were determined,and the dynamic changes of the physicochemical properties and the nitrate reductase and nitrite reductase activities of the simulated wastewater during incubation were also investigated.Results show that N_(2)O emission from the simulated wastewater was entirely caused by microbial pathway.The peak of deni⁃trification rate(N_(2)O+N_(2)emission rate,in terms of N)of the treatment DB appeared at 48 h,while that of the treatment DB+BC appeared at 36 h,and that of the treatment DB+WBC even appeared at 24 h.The maximum denitrification rates of DB+BC and DB+WBC(44087.79 and 46826.27 ng·h^(-1),respectively)were significantly higher than that of DB(38097.45 ng·h^(-1)).Compared with DB,the cumulative N_(2)O+N_(2)emissions of DB+BC and DB+WBC increased by 30.17%and 2.86%,respectively,while the cumulative N_(2)O emissions decreased by 83.04%and 74.52%,respectively,indicating that both BC and WBC increased the denitrification rate and promoted N_(2)O reduction.Compared with DB+BC,the cumulative N_(2)O+N_(2)emission of DB+WBC decreased by 20.98%,indicating that the denitrification promotion effect of bio⁃char skeleton was not as good as that of biochar,but its conductance structure still played an important role in denitrification.

关 键 词：稻壳生物炭 碳骨架 硝酸盐 反硝化作用 N_(2)O排放 

分 类 号：X52[环境科学与工程—环境工程]