改性稻壳生物炭对水中反硝化过程和N_(2)O排放的影响  

Effects of modified rice husk-derived biochar on denitrification and N_(2)O emission from water

作　　者：王朝旭[1] 刘勇超 常智淋 陈启斌[1] 王永 李作臣 闫铭 魏阳 WANG Chao-xu;LIU Yong-chao;CHANG Zhi-lin;CHEN Qi-bin;WANG Yong;LI Zuo-chen;YAN Ming;WEI Yang(College of Environmental Science and Engineering,Taiyuan University of Technology,Jinzhong 030600,China;Stecol Corporation North International Engineering Co.,Ltd.,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]中电建市政建设集团北方国际工程有限公司,山西晋中030600

出　　处：《中国环境科学》2023年第6期2908-2916,共9页China Environmental Science

基　　金：山西省自然科学基金资助项目(201901D111066)。

摘　　要：为探究H_(2)O_(2)改性和NaBH_(4)改性稻壳生物炭(BC-H_(2)O_(2)和BC-NaBH_(4))对反硝化过程和N_(2)O排放的影响及机理,在制备并测定BC-H_(2)O_(2)和BC-NaBH_(4)理化性质及其表面含氧官能团含量基础上,将未改性生物炭(BC)、BC-H_(2)O_(2)和BC-NaBH_(4)以1%(w/V)的比例分别加入含有厌氧反硝化细菌(DB)的培养体系,开展DB去除模拟废水中低浓度硝酸盐(约10mg/L,以N计)的室内培养实验.结果表明,H_(2)O_(2)改性增加了生物炭表面的羧基含量,而NaBH_(4)改性增加了生物炭表面的内酯基和酚羟基含量.另外,傅立叶变换红外光谱分析表明,与BC相比,BC-H_(2)O_(2)的C=O含量明显增加.DB+BC-H_(2)O_(2)和DB+BC-NaBH_(4)处理的反硝化速率峰值较DB+BC处理提前12h出现,且分别高17.50%和6.32%.与DB+BC处理相比,DB+BC-NaBH_(4)处理的N_(2)O累积排放量增加10.43%,但差异不显著;DB+BC-H_(2)O_(2)处理的N_(2)O累积排放量显著增加165.54%,N_(2)O/(N_(2)O+N_(2))比值显著增加170.00%,但N_(2)O+N_(2)累积排放量之间无显著差异(P<0.05),表明BC-H_(2)O_(2)抑制反硝化过程中N_(2)O向N_(2)还原,进而促进N_(2)O排放,这可能与添加BC-H_(2)O_(2)使培养体系的pH值、碳生物有效性降低以及C=O含量增加有关.The study focused on exploring the effects of H_(2)O_(2)-and NaBH_(4)-modified rice husk-derived biochars(BC-H_(2)O_(2)and BC-NaBH_(4))on denitrification and N_(2)O emission and the potential mechanisms.Based on BC-H_(2)O_(2)and BC-NaBH_(4)preparation and their physicochemical property and surface oxygen-containing functional group content determination,the pristine rice husk-derived biochar(BC),BC-H_(2)O_(2),and BC-NaBH_(4)were added into the incubation system containing the screened anaerobic denitrifier(DB)at the ratio of 1%(w/V),respectively.The microcosm incubation experiment was carried out to explore the removal efficiency of nitrate nitrogen(about 10mg/L)from simulated wastewater by DB.Results showed that H_(2)O_(2)-modification increased the carboxyl content on the surface of biochar,while NaBH_(4)-modification increased the contents of lactone and phenolic hydroxyl on the surface of biochar.In addition,the Fourier transform infrared spectra analysis showed that C=O content of BC-H_(2)O_(2)was significantly higher than that of BC.The denitrification rate peaks of DB+BC-H_(2)O_(2)and DB+BC-NaBH_(4)appeared 12h earlier and their values were 17.50%and 6.32%higher than that of DB+BC,respectively.Compared with DB+BC,the cumulative N_(2)O emission of DB+BC-NaBH_(4)increased by 10.43%,but the difference was not significant.However,the cumulative N_(2)O emission of DB+BC-H_(2)O_(2)increased by 165.54%and the N_(2)O/(N_(2)O+N_(2))ratio increased by 170.00%significantly,while there was no significant difference in the cumulative N_(2)O+N_(2)emission between DB+BC-H_(2)O_(2)and DB+BC(P<0.05).The result indicated that BC-H_(2)O_(2)inhibited N_(2)O reduction to N_(2)and promoted N_(2)O emission,which might be related to the decrease of pH and carbon bioavailability and the increase of C=O content induced by BC-H_(2)O_(2)amendment.

关 键 词：改性稻壳生物炭 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]