Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, 971 87 Luleå, Sweden.
J Contam Hydrol. 2013 Nov;154:70-7. doi: 10.1016/j.jconhyd.2013.08.007. Epub 2013 Aug 31.
Phosphorus filter units containing mineral-based sorbents with a high phosphate (PO4) binding capacity have been shown to be appropriate for removing PO4 in the treatment of domestic wastewater in on-site facilities. However, a better understanding of their PO4 removal mechanisms, and reactions that could lead to the formation of PO4 compounds, is required to evaluate the potential utility of candidate sorbents. Models based on data obtained from laboratory-scale experiments with columns of selected materials can be valuable for acquiring such understanding. Thus, in this study the transport and removal of PO4 in experiments with a laboratory-scale column filled with a commercial silicate-based sorbent were modeled, using the hydro-geochemical transport code PHREEQC. The resulting models, that incorporated the dissolution of calcite, kinetic constrains for the dissolution of calcium oxide (CaO) and wollastonite (CaSiO3), and the precipitation of amorphous tricalcium phosphate, Ca3(PO4)2, successfully simulated the removal of PO4 observed in the experiments.
含矿物质吸附剂的磷过滤单元具有较高的磷酸盐（PO4）结合能力，已被证明适用于现场设施中处理生活污水时去除 PO4。然而，为了评估候选吸附剂的潜在用途，需要更好地了解它们的 PO4 去除机制和可能导致 PO4 化合物形成的反应。基于选定材料柱的实验室规模实验数据的模型可以为获取这种理解提供有价值的信息。因此，在这项研究中，使用水文地球化学运输代码 PHREEQC 对填充有商业硅酸盐基吸附剂的实验室规模柱中进行的 PO4 传输和去除实验进行了建模。所得到的模型，纳入了方解石的溶解、氧化钙（CaO）和硅灰石（CaSiO3）溶解的动力学约束，以及无定形磷酸三钙（Ca3(PO4)2）的沉淀，成功地模拟了实验中观察到的 PO4 去除。
