红壤煤渣分层地下渗滤系统处理生活污水研究

Study on Treatment of Domestic Wastewater by Soil and Cinder Layered Subsurface Wastewater Infiltration system

为改善地下渗滤系统(SWIS)的水力渗透性,构建了1套红壤、煤渣分层装填地下渗滤系统,考察不同水力负荷下装置进出水中污染物含量的变化。结果表明,3种水力负荷(15、20、25 cm/d)下运行时,装置对COD、TP、NH_4^+-N、TN的平均去除率分别为90.31%、99.62%、94.61%、38.94%,93.01%、99.54%、87.19%、31.11%,91.99%、99.69%、45.06%、30.54%。COD及TP的去除效果良好,装置抗有机负荷冲击能力强;NH_4^+-N及TN的去除受水力负荷影响较大,水力负荷愈大,愈不利于NH_4^+-N和TN的去除。与USEPA推荐的6.6 cm/d相比,该装置的水力渗透性能显著提升。综合考察系统处理效率及出水水质,推荐水力负荷为15～20 cm/d。

To improve the hydraulic permeability of the subsurface wastewater infiltration system(SWIS), a set of red soil and cinder layered filling SWIS was constructed. The changes of pollutant content in the influent and effluent under different hydraulic loads were investigated. The results showed that,the average removal rates of COD, TP, NH4+-N and TN by system were 90.31%, 99.62%, 94.61%, 38.94% at 15 cm/d, 93.01%, 99.54%, 87.19%, 31.11%at 20 cm/d, and 91.99%, 99.69%, 45.06%, 30.54% at 25 cm/d, respectively. The removal rate of COD and TP was good, and the ability of the device to resisting organic load was strong under the three hydraulic loads. The removal of NH4+-N and TN was greatly affected by the hydraulic load, the greater the hydraulic load, the harder the removal of NH4+-N and TN. Compared with 6.6 cm/d recommended by USEPA, the hydraulic permeability of this device was significantly improved. The recommended hydraulic loads of this system was 15~20 cm/d, based on a comprehensive consideration of processing efficiency and effluent quality.