摘要
在中试过滤系统中,采用化学氧化法快速启动接触氧化滤池,即KMn O_4氧化Fe^(2+)、Mn^(2+)生成铁锰氧化物并沉积在石英砂表面形成活性氧化膜,通过活性氧化膜的化学作用同步去除水中NH_4^+-N、Fe^(2+)和Mn^(2+)。探究了滤池启动初期进水中Mn^(2+)被KMn O_4氧化2 mg/L后的富余量对滤池启动时间的影响,考察了Mn^(2+)富余浓度为0、1和2 mg/L三种挂膜条件下启动的滤池去除NH_4^+-N、Fe^(2+)和Mn^(2+)的能力以及滤速对除污效果的影响,启动后期不再投加KMn O_4。在滤池启动初期,进水Mn^(2+)富余2 mg/L的启动时间(15 d)比Mn^(2+)没有富余的滤池启动时间(27 d)缩短了44.4%,首次将滤池启动期缩短至20 d以内,此后可同步去除进水中1.5 mg/L的NH_4^+-N、1mg/L的Fe^(2+)和2 mg/L的Mn^(2+)。在所研究的滤速范围内(6~10 m/h),滤池除污能力受滤速影响较小,Fe^(2+)、NH_4^+-N和Mn^(2+)在滤池中依次被去除;滤池能同步去除Fe^(2+)、NH_4^+-N和Mn^(2+)的最大浓度为1、2和2 mg/L,满足多数受污染地下水的处理需求。另外,在处理高浓度氨氮(>2 mg/L)进水时,溶解氧是限制因素。
The quick start-up of the pilot-scale catalytic oxidation filter was conducted using chemical oxidation process, that was, KMnO4 oxidized Fe^2＋ , Mn^2＋ with the formation of Fe - Mn oxides and then Fe -Mn oxides deposited on the surface of quartz sand to form a co-oxide filter fihn, which could simultaneous remove NH4^＋ N, Fe^2＋ and Mn^2＋ by chemical action. The influent Mn2 ＋ of 2 mg/L was oxidized by KMnO4 at the initial stage of the start-up operation and the effect of surplus concentration was studied. Three different methods（ the concentration of 0,1 and 2 mg/L Mn^2＋ surplus） were employed to optimize the start-up process for simultaneous removal of NH4^＋ N, Fe^2＋ and Mn^2＋ from groundwater. The effect of filtration rate on the operation efficiency of the filters was also investigated. At the later stage of the start-up operation the KMnO4 would not he added into filter. The results showed that the start-up period of the filter with the concentrations of 2 mg/L surplus Mn^2＋ （15 d） was shorten by 44.4% compared to the concentrations of 0 mg/L surplus Mn^2＋ （27 d） . When the influent NH^4＋ - N, Fe^2＋ and Mn^2 ＋ concentration was 1.5 rag/L, 1 mg/L and 2 mg/L, the effluent could meet the standard of the water quality simultaneously in 15 days. This was the first study to shorten the start-up period into 20 days. When the filtration rate was 6 - 10 m/h, the removal capacity of pollutants of the filter was less affected by the filtration rate. Fe^2＋ , NH4^＋ N and Mn^2＋ in the filter was removed in accordance with the order. The maximum simultaneous removal of Fe^2＋ , NH4^＋ N and Mn^2＋ concentration were 1,2 and 2 mg/L under the experimental conditions, which could also meet the needs of the most contaminated groundwater treatment. In addition, dissolved oxygen was determined to be a limiting factor when the influent NH4^＋ N concentration was higher than 2 mg/L.
出处
《中国给水排水》
CAS
CSCD
北大核心
2017年第21期6-12,共7页
China Water & Wastewater
基金
国家重点研发计划课题(2016YFC0400706)
国家自然科学基金资助项目(51778521)
关键词
接触氧化法
化学氧化法
地下水
快速启动
氨氮
铁
锰
catalytic oxidation filter
chemical oxidation process
groundwater
quick start- up
ammonium
iron
manganese
