Department of Hydraulics and Sanitation, São Carlos School of Engineering, University of São Paulo, Trabalhador São-Carlense Avenue, 400, São Paulo, 13566-590, Brazil.
Department of Hydraulics and Sanitation, São Carlos School of Engineering, University of São Paulo, Trabalhador São-Carlense Avenue, 400, São Paulo, 13566-590, Brazil.
Water Res. 2019 Mar 1;150:29-39. doi: 10.1016/j.watres.2018.11.055. Epub 2018 Nov 21.
A household slow sand filter (HSSF) is a widely used water treatment technology recognized as one of the most effective and sustainable in reducing waterborne diseases. However, there is a lack of knowledge concerning its behaviour in the presence of cyanobacteria and cyanotoxins. In this context, the study aimed to evaluate HSSF ability to remove Microcystis aeruginosa cells (stain BB005) and microcystin-LR from water, among other parameters, when operated under continuous (C-HSSF) and intermittent (I-HSSF) flows. CHSSF was operated at a constant filtration rate (1.22 m m day), while I-HSSF was operated at a variable filtration rate (starting at 2.95 m m day and finishing at zero). Each filter produced 60 L day. The influence of the pause period was also tested in the I-HSSF. The water from the study was prepared by inoculating M. aeruginosa culture in water from a well to a final cell density of ± 1 × 10 cells mL. M. aeruginosa removal rates were 2.39 ± 0.34 log and 2.01 ± 0.43 log by CHSSF and I-HSSF, respectively. Microcystin-LR concentration in studied water was 5.55 μg L, and both filters produced filtered water with microcystin concentrations below 1.0 μg L, the maximum value recommended by the World Health Organization (WHO), for most of the samples. Turbidity and apparent colour were also within WHO guidelines. Filters operating with different flow regimes and distinct residence times did not statistically influence treatment efficiencies. Both filters showed promising results in the M. aeruginosa and microcystin-LR removals from water; nevertheless, more research is needed to understand the mechanisms involved in the reduction of both cyanobacteria and cyanotoxin through household slow sand filtration.
家用慢砂滤池（HSSF）是一种广泛应用的水处理技术，被认为是减少水传播疾病最有效和最可持续的方法之一。然而，关于其在存在蓝藻和蓝藻毒素时的行为，人们知之甚少。在这种情况下，本研究旨在评估 HSSF 去除水中铜绿微囊藻细胞（染色 BB005）和微囊藻毒素-LR 的能力，以及其他参数，当以连续（C-HSSF）和间歇（I-HSSF）流运行时。CHSSF 以恒定过滤速率（1.22 mm/d）运行，而 I-HSSF 以可变过滤速率（从 2.95 mm/d 开始，最终为零）运行。每个过滤器每天生产 60 L。还测试了 I-HSSF 中暂停期的影响。研究用水是通过将铜绿微囊藻培养物接种到井水中制备的，最终细胞密度为±1×10⁶个细胞/mL。CHSSF 和 I-HSSF 对铜绿微囊藻的去除率分别为 2.39±0.34 log 和 2.01±0.43 log。研究水中的微囊藻毒素-LR 浓度为 5.55 μg/L，两个过滤器都生产出微囊藻毒素浓度低于 1.0 μg/L 的过滤水，这是世界卫生组织（WHO）对大多数水样的推荐值。浊度和表观颜色也在 WHO 指南范围内。以不同流量模式和不同停留时间运行的过滤器在处理效率方面没有统计学上的影响。两个过滤器在去除水中铜绿微囊藻和微囊藻毒素-LR 方面都表现出了良好的效果；然而，需要进一步的研究来了解通过家用慢砂过滤去除蓝藻和蓝藻毒素的机制。
