铁基颗粒吸附剂固定床处理含砷地下水的中试研究
Pilot process of arsenic-containing groundwater purification by iron-based granular adsorbent fixed bed column
吴霄龙 1黄政宇 1李昂臻 2段常慧 3李荣乐 1吴鹍1
作者信息
- 1. 西安建筑科技大学环境与市政工程学院
- 2. 中国城市规划设计研究院
- 3. 长治市城市河道事务中心
- 折叠
摘要
以农村地区的As污染地下水为处理对象,研发了同步去除水中As(Ⅲ)和As(Ⅴ)的铁基颗粒吸附剂(FMGA),设计并建立了以吸附固定床为核心单元的中试除As装置,对As污染地下水的处理效果进行研究.结果表明:在 33 d的连续运行过程中,除As装置出水As浓度始终低于GB 5749-2022《生活饮用水卫生标准》规定限值(10 μg/L),吸附固定床首次运行的穿透时间达到 786 h;使用 0.2 mol/L的NaOH溶液对吸附剂进行原位再生后,吸附固定床再次运行的穿透时间仍可达到 750 h,其除As性能的恢复率接近 91%;除As装置的出水浊度接近于 0,Fe、Mn离子浓度均低于GB 5749-2022 的限值(Fe浓度为 0.3 mg/L,Mn浓度为 0.1 mg/L),FMGA可高效再生回用且无二次污染.吸附动力学表明,FMGA吸附As的过程符合准二级动力学模型,As通过化学吸附被去除;吸附等温线表明,FMGA对As的理论最大吸附容量为 74.94 mg/g(pH为 7.0).通过表征研究可知,FMGA最大荷载为 89.39 N,具有出色的机械强度.
Abstract
Arsenic(As)pollution in groundwater has become an important environmental issue in China.In order to purify the arsenic-contaminated groundwater in rural areas,an iron-based granular adsorbent(FMGA)capable of synchronously removing As(Ⅲ)and As(Ⅴ)from water was developed and packed into an adsorption fixed bed.A pilot-scale water treatment system was designed and established with a fixed bed as the core unit,which had a good capability for the treatment of As-contaminated groundwater.The results showed that during the continuous operation of 33 days,the residual As concentration in the effluent of the pilot-scale system was continuously below the limit of Standards for Drinking Water Quality(GB 5749-2022)(10 μg/L).The breakthrough time of the fixed bed reached 786 h in the first cycle.After the in-situ regeneration using 0.2 mol/L NaOH solution,the breakthrough time of the fixed bed for reuse could still reach 750 h,and the recovery rate of its arsenic adsorption capacity was close to 91%.The turbidity of the effluent for the pilot-scale system was close to zero,and the concentrations of iron and manganese ions were both lower than the limits of the sanitary standard(Fe<0.3 mg/L,Mn<0.1 mg/L).FMGA could be efficiently regenerated and reused without secondary pollution.The adsorption kinetics indicated that the adsorption process of As by FMGA was consistent with the quasi-second-order kinetic model,and As could be removed by chemisorption.The adsorption isotherm showed that the theoretical maximum adsorption capacity of FMGA for As was 74.94 mg/g(pH=7.0).According to the surface characterization results,the maximum load of FMGA was 89.39 N,indicating an excellent mechanical strength.
关键词
砷(As)/地下水/固定床/铁锰复合氧化物/颗粒吸附剂/中试试验Key words
arsenic(As)/groundwater/fixed bed/Fe-Mn composite oxide/granular adsorbent/pilot-scale experiment引用本文复制引用
基金项目
国家重点研发计划(2019YFD1100102-04)
住建部科技项目(2021-R-059)
长治市科技计划(1404992022CGK00545)
出版年
2024
NETL
NSTL
维普
万方数据