摘要
传统生物滞留系统对TSS、重金属和COD有较好的去除效果,但对N、P的去除效果不稳定。为了强化对N、P的去除,尝试用铝污泥和沸石对传统基质填料进行改良以提高系统对氨氮和磷的吸附效果,并在系统底部设置淹没区创造缺氧环境以提高系统对硝态氮的去除效果。模拟滞留柱试验采用15%铝污泥和85%沸石作为填料,对比了在无淹没区和有淹没区条件下对模拟雨水中各种污染物的去除效果。结果表明,在无淹没区条件下,系统对进水TSS负荷的变化有很好的抗冲击能力,当进水TSS为100~400 mg/L时,出水TSS浓度始终在20 mg/L以下。当进水COD为150~250 mg/L、TP为2.5~7 mg/L、NH_4^+-N为3~4 mg/L、NO_3^--N为6~10 mg/L时,系统对COD、TP、NH_4^+-N、NO_3^--N的平均去除率分别为76%、98%、97%、36%。在有淹没区且进水浓度基本相同的条件下,系统对TSS、COD、TP、NH_4^+-N等污染物的去除率较无淹没区时均没有大的变化,但对NO_3^--N的平均去除率则上升为79%。同时,系统对As、Pb、Zn、Cu、Hg、Cd、Cr等重金属也有良好的去除效果。添加铝污泥后提高了滞留系统对磷和重金属的控制能力。
Traditional bioretention system is effective in removing TSS, COD, and heavy metals while the removal efficiency of N and P is highly variable. Targeting at enhancing the removal of N and P, media was amended with aluminum-based water treatment residuals （AWTRs） and zeolite to adsorb N and P, ahd submerged area was designed at the bottom of the system to create a stable anaerobic zone for the removal of nitrates. A mixture of 15% AWTRs and 85% zeolite was used as the media in the bioretention system. The pollutants removal efficiencies were compared between bioretention systems with and without submerged area. The level of TSS in the effluent was maintained under 20 mg/L with the in- fluent TSS in range of 100 -400 mg/L. The levels of COD, TP, NH; - N and NO; - N in influent were 150-250 mg/L, 2.5 -7 mg/L, 3 -4 mg/L and 6 -10 mg/L respectively, and the average removal rates by the bioretention system without submerged area were 76%, 98%, 97% and 36%, respectively.Experiments indicated that creating a submerged area did not decrease the removal of TSS, COD, TP and NH4＋ - N. However, the NO3- - N removal rate was increased to 79%. In addition, the amended bioretention system presented enhanced performances in heavy metals removal.
出处
《中国给水排水》
CAS
CSCD
北大核心
2017年第7期157-162,共6页
China Water & Wastewater
基金
国家自然科学基金资助项目(51278024)
住房和城乡建设部科学技术项目(K42016090)
北京建筑大学科学研究基金资助项目(00331616055)
关键词
雨水生物滞留系统
基质改良
铝污泥
沸石
氮
磷
phorus bioretention system
media amendment
AWTR
zeolite
nitrogen
phosphorus
