原位生成铁锰复合氧化物在微絮凝/过滤工艺中除砷

Arsenic Removal by in Situ Formed Iron‑manganese Binary Oxide in Pilot‑scale Microflocculation-Filtration Process

针对传统吸附除砷(As)工艺所存在的吸附剂制备成本高、再生操作复杂以及固液分离困难等问题,开发了一种采用纤维球、锰砂作为填充滤料,使用在线加药原位生成的铁锰复合氧化物(FMBO)作为吸附剂的除砷新工艺。选用农村地区的砷污染地下水作为处理对象进行中试,在Fe^(3+)、Mn^(7+)、Mn^(2+)投加量分别为1.75、0.1和0.15 mg/L,水力停留时间为15 min的最佳条件下运行了5个周期,出水砷、铁和锰浓度分别稳定在10μg/L、0.3 mg/L和0.1 mg/L以下,均达到了《生活饮用水卫生标准》(GB 5749—2022)中的限值要求,且运行成本仅约为0.91元/m^(3)。与其他地下水除砷工艺相比,该技术更加经济高效。

A novel arsenic(As)removal technology was developed in response to the shortcomings of traditional adsorption‑based methods,such as high adsorbent preparation costs,complex regeneration procedures,and difficult solid‑liquid separation.This new approach utilized fiber balls and manganese sand as filling materials,and employed an iron‑manganese binary oxide generated in situ by online dosing as the adsorbent.The arsenic contaminated groundwater in rural areas was selected as the target in this pilot scale test.The results showed that after five cycles of operation under optimal conditions of Fe^(3+)dosing at 1.75 mg/L,Mn^(7+)dosing at 0.1 mg/L,Mn^(2+)dosing at 0.15 mg/L,and hydraulic retention time of 15 minutes,the concentrations of As,Fe,and Mn in the effluent were stable below 10μg/L,0.3 mg/L and 0.1 mg/L,and were all below the limit values stipulated in the Standards for Drinking Water Quality(GB 5749-2022).Moreover,the operating cost of this technique was only about 0.91 yuan/m^(3).Compared with other techniques for removing arsenic from groundwater,it was more cost‑effective.