摘要
厌氧铁氨氧化(ammonium oxidation coupling with iron reduction,Feammox)反应是一种在厌氧条件下,由厌氧铁氨氧化菌驱动,以三价铁为电子受体,氧化氨氮的生物化学途径,它可以用于去除水体中的氨氮.为提高厌氧铁氨氧化菌对氨氮废水处理效果,采用"氢氧化钠共沉淀-溶胶-凝胶"法制备粒径为1~5mm的磁性壳聚糖凝胶球(magnetic chitosan hydrogel beads,MCHBs),将厌氧铁氨氧化菌固定,研究其对废水中氨氮去除效果和影响因素,并与游离厌氧铁氨氧化菌对废水氨氮去除效率作对比.制备的MCHBs进行X射线衍射(XRD)和振动样品磁强(VSM)等表征分析.结果表明,MCHBs为铁磁性、结晶度高,饱和磁化强度达29.46 emu·g^(-1).MCHBs固定厌氧铁氨氧化菌比游离菌具有更高的氨氧化和铁还原速率,平均增幅为42.96%和20.75%,以MCHBs(1~2 mm)固定厌氧铁氨氧化菌的效果最显著(P<0.05).进一步研究发现,不适宜氨氮浓度、温度和pH下,MCHBs(1~2 mm)固定厌氧铁氨氧化菌氧化氨氮的能力均比游离菌高.初始氨氮浓度60.00 mg·L^(-1)、温度25℃和pH 4.50时,厌氧铁氨氧化效果较好,主要产物为硝态氮和二价铁,16 d时MCHBs(1~2 mm)固定厌氧铁氨氧化菌对氨氮去除率高达53.62%.这些结果都表明以MCHBs固定厌氧铁氨氧化菌后,能起到增强厌氧铁氨氧化反应去除废水氨氮的目的.
The bacterial reaction of ammonium oxidation coupling with iron reduction（ Feammox） has been discovered recently. To improve the ammonium removal efficiency from wastewater of Feammox bacteria,magnetic chitosan hydrogel beads（ MCHBs） were prepared via sodium hydroxide co-precipitating-sol-gel method,Feammox bacteria were immobilized to 1-5 mm MCHBs,and the ammonium removal efficiency by MCHBs-Feammox bacteria was compared to free-Feammox bacteria. In addition,the influences of initial ammonium concentration,p H and temperature were assessed. The results showed that the MCHBs were ferromagnetic and exhibited high crystallinity,with the magnetization of saturation of 29. 46 emu·g^-1. The average rates of ammonia oxidation and iron reduction increased by 42. 96% and 20. 75% after Feammox bacteria immobilization,respectively,and the most significant effect was observed on 1-2 mm MCHBs-Feammox bacteria（ P〈0. 05）. Furthermore,1-2 mm MCHBs immobilized bacteria worked in less favorable matrix concentrations,temperatures,and pH. Particularly,it could maintain high ammonium removal efficiency with 60. 00 mg·L^-1 initial ammonium concentration,25℃ temperature and 4. 50 pH. In addition,nitrate and ferrous ions were detected in the system. The highest ammonium removal rate occurred on day 16, reaching 53. 62%. These results indicated that MCHBs immobilization can improve the ammonium removal efficiency of Feammox.
作者
刘志文
陈琛
彭晓春
谢武明
黄镇扬
韩庆吉
LIU Zhi-wen;CHEN Chen;PENG Xiao-chun;XIE Wu-ming;HUANG Zhen-yang;HAN Qing-ji(School of Environmental Science and Engineering,Guangdong University of Technology,Guangzhou 510006,China;South China Institute of Environmental Seienee,Ministry of Environmental Protection,Guangzhou 510535,China;Guangdong Province Vocational School of Oceanographic Engineering,Guangzhou 510320,China;College of Architecture and Civil Engineering,Xi＇an University of Science and Technology,Xi＇an 710054,China)
出处
《环境科学》
EI
CAS
CSCD
北大核心
2018年第10期4601-4611,共11页
Environmental Science
基金
国家重点研发计划项目(2016YFE0106600)
国家自然科学基金项目(41501278)
环境保护部留学人员择优资助项目(PM-zx421-201612-333)
广东省省级财政技术研究开发补助经费入库项目(PM-zx097-201601-024)
广州市科技计划项目(2016201604040057)
关键词
固定化
厌氧铁氨氧化
磁性壳聚糖凝胶球(MCHBs)
氨氮去除
Fe(Ⅲ)还原
immobilization
ammonium oxidation coupling with iron reduction （Feammox）
magnetic chitosan hydrogel beads （MCHBs）
ammonium removal
iron reduction
