改性活性氧化铝强化屋顶收集雨水中氮磷的协同吸附效能

用于景观水回用的屋面收集雨水水质需严格控制氮、磷含量,以避免富营养化和藻类滋生现象。文中针对活性氧化铝的氮、磷吸附作用,采用浸渍法制备了改性活性氧化铝,表征了改性活性氧化铝的氨氮吸附规律、理化特性和主要影响因素,对比了改性前后活性氧化铝单独吸附和协同吸附的氨氮和总磷的吸附效能。结果表明:改性活性氧化铝的酸性含氧官能团数量增多、离子交换能力提高,氨氮吸附容量增大了17.39%;活性氧化铝和改性活性氧化铝的氨氮吸附特性更符合拟二级动力学和Freundlich规律,高温更有利于改性活性氧化铝的氨氮吸附,弱酸性至中性是氨氮吸附效果最佳pH,当有机物与氨氮同时存在时,会发生明显的竞争吸附现象。改性活性氧化铝单独吸附与协同吸附氨氮和总磷的去除效能均得到明显改善,氮、磷协同吸附时氨氮和总磷去除率分别达55.46%和97.22%,比活性氧化铝提高了14.05个百分点和5.01个百分点。研究成果为屋面收集雨水的高效净化技术及其在景观水体的安全回用提供了参考。

北方城市雨洪径流水质和利用模式探讨

根据北方城市水资源紧缺而雨水资源却未被充分利用这一情况,以河北省邯郸市为例,探讨了适合北方城市气候特点和经济发展的2种雨洪利用工程模式——道路雨水收集利用和屋顶雨水收集利用;同时针对城市道路降雨径流污染严重,以及初期雨水的污染程度通常超过城市污水的现状,分析了雨水中各种污染物的浓度,并与灌溉水质标准进行了对比;对路面径流的水质特性、次降雨产流过程中污染物浓度的变化规律也进行了分析研究,建立了污染物冲刷排放规律数学模型,以期为城市道路径流利用提供基础资料。

Sustainable Water Supply for Domestic Use： Application of Roof-Harvested Water for Ground Water Recharge

Rain water harvesting offers a wealth of promising possibilities for many countries. This paper describes a study in which rainwater harvested from the rooftop is used for recharging groundwater in a household well in Ibadan. A rainwater harvesting structure was designed to be 1.2 m deep, 2.6 m long and 0.66 m wide, filled with gravel and fine sand at different layers. Rainwater harvested in a storage tank is passed with the aid of a hose pipe to the rainwater harvesting structure on a daily basis to recharge the groundwater in the well. A well in the neighborhood serves as control for this experiment, which went on for a month. The volume of rainwater used to recharge the groundwater in the well was recorded daily for the study period. The results indicated that using rainwater to recharge the groundwater in the well led to conservation of the water in the well through reduced evaporation. Thus, the well yields water all the year round as compared to the control well that dries up during the dry season.