改性石英砂过滤技术用于污水再生回用的研究

Study on Modified Quartz Sand Filtration Technology for Wastewater Reclamation and Reuse

通过对石英砂滤料进行改性,研究了改性后滤料表面性能的变化,考察了不同改性滤料对城市污水厂二级处理出水中污染物的去除效果。表面性能分析的结果表明,经不同改性剂涂层后其表面性能存在差异,其中铁铝砂、铁砂及SJ型砂的物理稳定性较好,且表面含有金属氧化物,因而提高了滤料的截污性能。二级处理出水的过滤试验表明,石英砂、铁铝砂、铁砂和SJ型砂对浊度的去除率均在60%以上;与石英砂相比,改性砂对COD、UV254和PO34--P的去除率均有所提高,且过滤出水中的PO43--P<1mg/L,其中铁砂和SJ型砂的过滤效果稳定,对COD、UV254和PO43--P的平均去除率提高明显,分别提高了26%、79%和40%以上。改性滤料经再生后可以重复使用,在城市污水再生回用中具有良好的应用前景。

The surface performance of modified quartz sand media was studied, and the effect of filter media coated with different modifying agents on the removal of pollutants from secondary effluent of municipal wastewater treatment plants was investigated. The results show that there is difference in surface performance among filter media coated with different modifying agents. Among them, the surface physical stability of iron-aluminum-coated sand, iron-coated sand and SJ material-coated sand is better, and there are metal oxides with adsorption capability on their surfaces. The filtration test of secondary effluent indicates that the removal rate of turbidity by natural quartz sand, iron-aluminum-coated sand, iron-coated sand and SJ material-coated sand is more than 60%. Compared with natural quartz sand, the removal rates of COD, UV254 and PO4^3- -P by modified quartz sands are improved to a certain extent, and the concentrations of PO4^3- -P in filtration effluent are all less than 1 mg/L. Among them, iron-coated sand and SJ material-coated sand have more stable filtration efficiency, and the average removal rates of COD. UV254 and PO4^3- -P are increased by more than 26% , 79% and 40% respectively compared with natural quartz sand. Moreover. the filter media coated with different modifying agents can be reused after be regenerated and have a good application prospect in reclamation and reuse of municipal wastewater.