砂滤工艺处理西北黄土塬地区集雨水石英砂改性及滤速选定试验

摘要

Experiment on quartz sand modification and filtration rate selection for removing the contaminant from rain water in northwest loess tableland area was carried out.The optimal concentration,stirring number calcinations temperature and time of the modifier (FeCl3) were determined by CODc,removing rate.Concentration and adhesion strength of the material covering quartz sand were measured under the optimal modification conditions.Results turned out that the optimal modification concentration was 2 mol/L,no stirring,calcinations temperature was 550 ℃,and calcinations time was 3 h.The content of surface coating material was 2.14 mg/g,and desorption rates were 0.551％ and 0.119％ under the condition of acid and mechanical shock.The optimal filtration rate was determined to be 6 m/h,through the analysis of effluent turbidity and periodic total water quantity by different filtration rate.%对处理西北黄土塬地区集雨水砂滤工艺的石英砂滤料进行了改性试验,同时进行了滤速的选定试验.通过改性滤料对CODCr的去除率确定改性剂(三氯化铁)的最佳浓度、改性滤料在烘箱中被搅拌的最佳次数、最佳焙烧温度及最佳焙烧时间,确定了最佳改性条件下表面覆膜物质含量及氧化膜的附着强度.试验结果表明:改性剂浓度为2 mol/L,无搅拌,焙烧温度为550℃,焙烧时间为3h时,所得到的改性滤料对集雨水CODCr的去除效果最好;最佳改性条件下表面覆膜物质的含量为2.14 mg/g,其在酸性和机械震荡条件下的脱附率分别为0.551％、0.119％.在砂滤滤速的选定试验中,通过对不同滤速下,出水的浊度和总产水量分析,选定了最佳滤速为6 m/h.