城市污水厂出水直接进入天然水体、或经过深度处理后回用于灌溉、补充景观水体和回灌地下水,均需要进行安全性评价.针对北京市北小河污水处理厂出水经过深度处理后回用于奥运公园的安全性,比较了不同深度处理工艺对营养盐(氮、磷)总量和不同形态的去除效果.研究表明,二级处理本身对氮磷的去除效果十分有限,回用水需经过深度处理.在所研究的生物活性炭吸附、微滤、超滤、反渗透以及上述技术的组合工艺中,使用超滤和反渗透联用的工艺路线对脱氮除磷的效果较为理想,其他工艺对去除氮磷的效果十分有限.
Environmental risk assessment is required for direct discharge of effluent from wastewater treatment plant into receiving waters. Risk assessment is also necessary for effluents from advanced treatment units when used for irrigation, for backfill to ground water, as well as for sight waters. In this paper, removal efficiencies of different chemical forms of nitrogen and phosphorus from secondary effluent of the Beixiaohe Wastewater Treatment Plant and by using advanced treatment technologies were evaluated, regarding to the re-use for sight water of the Olympic Park. The resuhs showed that secondary treatment could hardly remove nutrients and reclamation technologies should be applied. Among biologic activated carbon adsorption, microfiltration, ultrafiltration, reverse osmosis, as well as their combinations, the combined reactor based on both ultrafiltration and reverse osmosis was the most effective one, while other technologies were not suitable for removal of both nitrogen and phosphorus from secondary effluent.