人工湿地中除磷填料的筛选及其除磷能力

针对猪场废水水质特点,对4种填料的理化特性进行了分析,并考察了4种填料的除磷能力.结果表明,废砖块和沸石的表面微结构更有利于生物膜的生长,而海蛎壳与废砖块则具有较高的除磷潜能;4种填料对磷素的理论饱和吸附量依次为海砺壳>废砖块>火山岩>沸石,海蛎壳对磷素的吸附主要为化学吸附,而废砖块、火山岩和沸石对磷素的吸附主要为物理吸附,其中废砖块对磷素的吸附过程中存在化学吸附作用;在动态吸附试验中,海蛎壳对磷素的去除效果最好,其次为废砖块、火山岩和沸石,4种填料去除磷素的主要途径由其化学成分和化学形态决定.由试验结果可知,海蛎壳是人工湿地处理猪场废水时较为理想的除磷填料.

Screening of phosphate-removing filter media for use in constructed wetlands and their phosphorus removal capacities

According to the characteristics of swine wastewater, physico-chemical properties of oyster shell (OS), broken bricks, volcanics, and zeolite were determined, as well as their phosphorus removal capacities. The results showed that, broken bricks and zeolite showed more suitable potential environments for biofilm bacterial growth, whereas OS and broken bricks possessed of high potential capacities for phosphorus removal. OS had the highest phosphorus adsorption value by isothermal adsorption tests, followed by broken bricks, volcanics, and zeolite, the type of adsorption of PO43- on OS was defined as chemical adsorption, the types of adsorption of PO43- on broken bricks, volcanics, and zeolite were defined as physical adsorption, and the process that occurred during phosphorus adsorption on broken bricks was understood to be chemical adsorption. OS was most effective at phosphorus removal in the dynamic adsorption experiments, followed by broken bricks, volcanics, and zeolite. Besides, the main phosphorus removal pathway of each filter medium was determined by the contents and chemical forms of elements in the filter medium. In conclusion, OS should be the ideal filter medium used in constructed wetlands treating swine wastewater.