曝气对污水地下渗滤系统渗透性及处理性能的影响

Effects of aeration on permeability and treatment performance of subsurface wastewater infiltration system

针对气体影响地下渗滤系统的渗透性及污水处理效果的问题,用地下渗滤系统处理不同曝气程度的生活污水,研究曝气对不同深度基质理化性质(渗透系数、体积含水率、气体类型及浓度)和出水水质的影响。结果表明,曝气增加了-130^-100、-40^-10 cm处的渗透系数,降低了-100^-70 cm处的渗透系数,与-70^-40 cm处的渗透系数不存在相关关系;曝气增加了-70 cm处的体积含水率,降低了-100 cm和-40 cm处的体积含水率,对-10 cm处的体积含水率几乎没有影响;曝气增加了各深度处的CO^2、N^2O释放浓度,与各深处的CH^4释放浓度不存在相关关系;曝气增加了NH^+4-N和COD去除率,与NO^-3-N、NO-^2-N和TP去除率不存在相关关系。探明了气体对地下渗滤系统处理性能的影响,为气体堵塞及其预防提供了参考。

In order to identify the effects of gas on the soil permeability and sewage treatment of subsurface wastewater treatment system(SWIS),domestic wastewater with different aeration treatment was introduced into a set of SWIS to study the effect of aeration on the physicochemical properties(permeability coefficient,volumetric water content,gas types and concentrations)of the matrix at different depths and effluent quality.The results indicated that aeration improved the permeability coefficients at-130^-100 cm and-40^-10 cm,reduced the permeability coefficient at-100^-70 cm,had an insignificant correlation with the permeability coefficient at-70^-40 cm.Meanwhile,the aeration elevated the volumetric water content at-70 cm,reduced the volumetric water content at-100 cm and-40 cm,had slight influence on the volumetric water content at-10 cm.Aeration improved the releasing concentrations of CO^2 and N^2O at different depths,and had an insignificant correlation with CH^4 releasing concentrations.Aeration treatment of raw water improved theremoval rates of NH+4-N, COD and TP, reduced NO^-3-N removal rate,and had no correlation with NO^-2-N removal.The effects of gas on SWIS were preliminarily identified,which provided references for further research on gas clogging and its prevention.