粉煤灰吸附处理初期雨水中总磷和化学需氧量的研究

初期雨水污染是雨水径流污染的主要贡献者。以粉煤灰和改性后的粉煤灰（MFA）为对象,研究其作为吸附剂时不同投加量、吸附时间、pH等条件下对初期雨水中总磷和化学需氧量（COD）去除的影响,确定最佳吸附条件,并对吸附结果进行数据拟合,建立吸附等温模型和吸附动力学模型。结果表明,MFA吸附效果明显提高,100 mL初期雨水中MFA投加量1.5 g、pH=8、吸附时间40 min时,对总磷的吸附效率可达93.83%;投加量1.0 g、pH=6,吸附时间40 min时,对COD的吸附效率可达77.66%。MFA吸附总磷的过程符合Freundlich吸附等温模型和二级动力学模型,吸附COD的过程符合Langmuir吸附等温模型和二级动力学模型。

Research on the treatment of total phosphorus and chemical oxygen demand using fly ash in the initial rainwater

he initial rainwater pollution mainly contributes to rainwater runoff pollution. In this paper, the adsorption effects of fly ash and modified fly ash (MFA) on the removal of total phosphorus and chemical oxygen demand (COD) in the initial rainwater were investigated under various conditions such as different dosage, adsorption time, and pH. Moreover, optimal adsorption conditions were determined, and the adsorption results were fitted with the data to establish the adsorption isotherm and kinetic models. The result showed that the adsorption effect of MFA was considerably improved. The adsorption efficiency of total phosphorus reached 93.83% when the dosage of MFA in rainwater, pH, and adsorption time were 1.5 g, 8, and 40 min; the adsorption efficiency of COD reached 77.66% when the dosage, pH, and adsorption time were 1.0 g, 6, and 40 min. Furthermore, the adsorption process of total phosphorus using MFA fits the Freundlich adsorption isotherm model and second-order kinetic model, and the adsorption process of COD fits the Langmuir adsorption isotherm model and second-order kinetic model.