石英砂加载混凝工艺的DOM去除特征与混凝机理

为处理未纳入管网的市政污水,采用石英砂加载混凝工艺,考察石英砂的粒径及其投加量对处理效能的影响,分析了溶解性有机物(dissolved organic matters,DOM)的去除特征,并探讨了石英砂加载混凝机理.结果 表明,与常规混凝相比,当石英砂的粒径和投加量分别为200目和1.0 mg/L时,石英砂加载混凝工艺...

DOM removal characteristics and coagulation mechanism of silica sand loading coagulation process

In order to treat municipal wastewater not included in the pipe network, silica sand loading coagulation process was adopted. The effects of particle size and dosage of silica sand on the treatment efficiency were investigated, the removal characteristics of dissolved organic matters(DOM)were analyzed, and the coagulation mechanism was discussed. The results show that when the particle size and dosage of silica sand are 200 mesh and 1. 0 mg/L, respectively, the removal rates of turbidity and COD by silica sand loading coagulation are 97. 55% and 59. 2%, respectively, which are better than the conventional coagulation. The aromatic, conjugated double bond and hydrophobic organic matter can be obviously removed by silica sand loading coagulation, which mainly promotes the reduction of humus. Through bridging, silica sand increases the density of flocs, and then significantly improves the settlement performance and strength of flocs. The settling property, strength and re stability of flocs increase with the decrease of silica sand particle size.