School of Engineering, University of Guelph, Guelph, ON, Canada.
J Environ Sci Health A Tox Hazard Subst Environ Eng. 2011;46(4):426-35. doi: 10.1080/10934529.2011.549409.
Arsenic iron removal plants (AIRPs) are used in some locations in Bangladesh to remove arsenic from groundwater to provide access to safer drinking water. In this study, the influence of orthophosphate in influent water on the performance of 21 (of 105) AIRPs installed in the Manikganj District was evaluated. The degree of aeration was also estimated, and the role of dissolved oxygen in AIRP performance is discussed. AIRP installations were done by a local non-governmental organization (The Society for People's Action in Change and Equity) with financial assistance from the Australian High Commission, Dhaka under the Direct Aid Program of the Australian Government. The presence of orthophosphate in the influent did not influence arsenic removal efficiency in the tested AIRPs, likely due to the high iron concentrations at all sites. The high iron provides adequate surface area for both orthophosphate and arsenic to be removed. Orthophosphate co-precipitated with iron oxides much more quickly than arsenic, in one cleaning cycle study, and is expected to play a more significant role in interfering with arsenic removal at sites with much lower iron concentrations. The aeration trays studied are estimated to introduce at least 2.4-3.7 mg/L of dissolved oxygen. In normal operation, sufficient oxygen is introduced through the aeration tray to fully oxidize all influent iron. The AIRPs studied show promise for use in areas of Bangladesh with high natural iron, where users are concerned with arsenic, iron, or both, in their drinking water.
砷铁去除厂（AIRP）在孟加拉国的一些地区被用于从地下水去除砷，以提供更安全的饮用水。本研究评估了进水中原磷酸盐对在曼尼甘杰区安装的 105 个 AIRP 中 21 个的性能的影响。还估计了充氧量，并讨论了溶解氧在 AIRP 性能中的作用。AIRP 是由当地非政府组织（人民行动协会变革与公平）在澳大利亚驻达卡高级委员会的直接援助计划下，在澳大利亚政府的财政援助下安装的。进水中原磷酸盐的存在并没有影响测试中的 AIRP 的除砷效率，这可能是由于所有地点的铁浓度都很高。高浓度的铁为原磷酸盐和砷提供了足够的表面积，使其得以去除。在一个清洗周期的研究中，原磷酸盐与氧化铁一起迅速共沉淀，预计在铁浓度较低的地点，原磷酸盐会在干扰砷去除方面发挥更重要的作用。研究中所研究的曝气盘估计至少引入了 2.4-3.7mg/L 的溶解氧。在正常运行中，通过曝气盘引入了足够的氧气，可将所有进水铁完全氧化。在孟加拉国高天然铁地区，用户关心饮用水中的砷、铁或两者，研究中的 AIRP 具有应用前景。
