This study evaluated the performance of a low-cost natural laterite from Thach That (NLTT), Vietnam, for its capacity to remove arsenic (As) in a household filter with contaminated groundwater. The NLTT was initially tested in a laboratory column trial lasting 800 h. The breakthrough curves were found to fit the Thomas model very satisfactorily with adsorption capacities of 0.06 and 0.20 mg/g at a flow velocity of 0.85 m/h for the influent As(V) concentrations of 0.1 and 0.5 mg/L, respectively. In household filters at four sites, the median As concentration in groundwaters (0.04–0.19 mg/L) dropped to 0.026–0.054 mg/L after traditional sand filtration. However, following subsequent NLTT filtration through columns (14 cm inner diameter, 65 cm height) at 0.65 m/h flow velocity, it fell to below the Vietnam and WHO drinking water standard (0.01 mg/L) during seven months of continuous operation. Portland cement and lime were tested as binding agents for the exhausted NLTT waste in a solidification/stabilization process at different ratios. The best ratio of exhausted NLTT: Portland cement: lime for restraining mobility of As from this waste was 3:1:0.5. The concrete brick products exhibited a suitable compressive strength for using it as building materials in construction work.

本研究评估了来自越南 Thach That (NLTT) 的低成本天然红土去除受污染地下水的家用过滤器中砷 (As) 的能力。NLTT 最初在持续 800 小时的实验室色谱柱试验中进行了测试。发现穿透曲线非常符合 Thomas 模型，在 0.85 m/h 的流速下，对于 0.1 和 0.5 mg/L 的进水 As(V) 浓度，吸附容量分别为 0.06 和 0.20 mg/g。在四个地点的家用过滤器中，地下水中的砷浓度中值（0.04-0.19 毫克/升）经过传统的砂滤后降至 0.026-0.054 毫克/升。然而，在随后以 0.65 m/h 流速通过柱子（内径 14 cm，高度 65 cm）进行 NLTT 过滤后，它下降到低于越南和世界卫生组织的饮用水标准（0. 01 mg/L) 连续运行七个月。将波特兰水泥和石灰作为固化/稳定过程中用尽的 NLTT 废物的粘合剂以不同的比例进行测试。用尽NLTT: 波特兰水泥: 石灰的最佳比例是3:1:0.5。混凝土砖产品表现出合适的抗压强度，可将其用作建筑工程中的建筑材料。