In order to enhance the hydraulic loading rate(HLR) of a subsurface wastewater infiltration system(SWIS) used in treating domestic sewage,the intermittent operation mode was employed in the SWIS. The results show that the intermittent operation mode contributes to the improvement of the HLR and the pollutant removal rate. When the wetting-drying ratio(R WD) was 1.0, the pollutant removal rate increased by(13.6 ± 0.3)% for NH3-N,(20.7 ± 1.1)% for TN,(18.6 ± 0.4)% for TP,(12.2 ± 0.5)% for BOD,(10.1 ± 0.3)% for COD, and(36.2 ± 1.2)% for SS, compared with pollutant removal rates under the continuous operation mode. The pollutant removal rate declined with the increase of the HLR. The effluent quality met The Reuse of Urban Recycling Water e Water Quality Standard for Scenic Environment Use(GB/T 18921-2002)even when the HLR was as high as 10 cm/d. Hydraulic conductivity, oxidation reduction potential(ORP), the quantity of nitrifying bacteria, and the pollutant removal rate of NH3-N increased with the decrease of the R WD. For the pollutant removal rates of TP, BOD, and COD, there were no significant difference( p < 0.05) under different R WD s. The suggested R WD was 1.0. Relative contribution of the pretreatment and SWIS to the pollutant removal was examined, and more than 80% removal of NH3-N, TN, TP, COD, and BOD occurred in the SWIS.
面对越来越严重的城市面源污染问题,提出岸堤式漫流阻控技术,其中植物与基质是漫流系统的重要组成部分,植物与基质的组配是否合理严重影响漫流系统对污水的净化效果。试验通过建立不同的岸堤漫流系统研究不同基质和不同植物组合对漫流系统净化效率和效率稳定性的影响。结果表明,炉渣、黄土和沙子的混合基质比黄土、棕壤土这种单一基质的净化效率高,特别是对悬浮固体(SS)、氨态氮(NH3-N)、总磷(TP)的去除,去除率均在60%以上;高羊茅(Festuca elata Keng ex E.Alexeev)比黑麦草(Lolium perenne L.)更适合于漫流系统。高羊茅与混合基质的组合为岸堤漫流系统最优的基质、植物配置方式。
