研究报告
王依婷,汪宇,高宇,张琼,李韧,于莉芳,彭党聪.Fe3+对MBBR系统脱氮途径及关键酶性能影响分析[J].环境科学学报,2022,42(5):169-177
Fe3+对MBBR系统脱氮途径及关键酶性能影响分析
- Effect of Fe3+ on the nitrogen removal pathway and related key enzymes in an MBBR system
- 基金项目:陕西省自然科学基金项目(No.2020JM-474);陕西省重点研发计划项目(No.2019ZDLSF0605);碑林区科技计划项目(No.GX2013);西安建筑科技大学基金项目(No.ZR20020)
- 王依婷
- 西安建筑科技大学环境与市政工程学院,西安 710055;西安建筑科技大学西北水资源与环境生态教育部重点实验室,西安 710055
- 汪宇
- 西安建筑科技大学环境与市政工程学院,西安 710055
- 高宇
- 西安建筑科技大学环境与市政工程学院,西安 710055
- 张琼
- 西安建筑科技大学环境与市政工程学院,西安 710055
- 李韧
- 西安建筑科技大学环境与市政工程学院,西安 710055
- 于莉芳
- 西安建筑科技大学环境与市政工程学院,西安 710055;西安建筑科技大学西北水资源与环境生态教育部重点实验室,西安 710055
- 彭党聪
- 西安建筑科技大学环境与市政工程学院,西安 710055;西安建筑科技大学西北水资源与环境生态教育部重点实验室,西安 710055
- 摘要:为考察Fe3+对移动床生物膜系统(Moving-bed Biofilm Reactor, MBBR)脱氮途径及相关酶活性的影响,以15 ℃下长期运行的移动床生物膜为研究对象,确定Fe3+的最佳投加浓度,在此基础上,启动运行MBBR1(添加 Fe3+)与MBBR2(不添加Fe3+),对比分析了两反应器脱氮性能、相关酶活性、微生物群落结构及脱氮途径.结果表明,添加10 mg·L-1 Fe3+的MBBR1与MBBR2相比,氨氧化、亚硝酸盐氧化、硝酸盐还原及亚硝酸盐还原的速率分别增加了75%、3%、10%和6%,氨单加氧化酶(Ammonia Monooxygenase, AMO)、羟胺氧化酶(Hydroxylamine Oxidoreductase, HAO)、亚硝酸盐氧化酶(Nitrite Oxidoreductase, NXR)、硝酸盐还原酶(Nitrate Reductase, NAR)和亚硝酸盐还原酶(Nitrite Reductase, NIR)的活性分别增加了10%、13%、2%、108%和3%,总氮去除率提高了11.17%.Illumina MiSeq测序结果表明,MBBR1中Nitrosomonas与Thauera相对丰度均高于MBBR2,NOB相对丰度接近.模型计算结果显示,MBBR1主要脱氮途径为同步短程硝化反硝化,而MBBR2主要脱氮途径为全程硝化反硝化.综上,Fe3+可通过影响脱氮过程中关键酶活性及生物群落结构,强化MBBR系统同步短程硝化反硝化能力以提高MBBR系统脱氮性能.
- Abstract:In order to clarify the effect of Fe3+ on the nitrogen removal pathway of the biofilm system, two moving bed biofilm reactors (MBBRs) were synchronously operated at 15 ℃, with one being fed with 10 mg ?L-1 Fe3+ (MBBR1), which was the optimal dosing concentration determined by batch tests, and the other without Fe3+ addition (MBBR2). Compared to MBBR2, the metabolic rates of ammonium oxidation, nitrite oxidation, nitrate reduction, and nitrite reduction in MBBR1 were increased by 75%, 3%, 10% and 6%, respectively. Meanwhile, the enzymatic activities of ammonia monooxygenase, hydroxylamine oxidoreductase, nitrite oxidoreductase, nitrate reductase and nitrite reductase in MBBR1 were increased by 10%, 13%, 2%, 108% and 3% respectively, compared with those of MBBR2. Thus, TN removal rate of MBBR1 was 11.17% higher than that of MBBR2. The Illumina MiSeq sequencing revealed that the relative abundance of Nitrosomonas and Thauera in MBBR1 were higher than those in MBBR2, while there was no significant difference between the abundance of NOB in MBBR1 and MBBR2. The calculating results showed that the dominant pathway of nitrogen removal was simultaneous partial nitrification and denitrification (SPND) in the MBBR1, while it was full nitrification and denitrification in the MBBR2. These results indicated that Fe3+ addition could enhance the SPND process to improve the nitrogen removal performance by affecting the key enzymatic activities and community structure of the MBBR system.