河流护岸多孔生态材料对水体中硝态氮去除试验

Experiment of porous ecological material of river revetment on removal of nitrate nitrogen in water

为进一步提升护岸材料对面源污染物的净化能力,采用骨料交联法制备了具有较高透水率的多孔生态砌块,研究骨料粒径与砌块透水率的关系,并采用动水挂膜法对不同透水率的生态砌块进行反硝化细菌表面负载,在此基础上,研究所制备的不同骨料粒径的生态砌块的透水率、比表面积等对水体中硝态氮去除率的耦合效应。结果表明:在相同孔隙率条件下生态砌块的透水率随比表面积的增加而降低,且随着骨料粒径的增大而提高;生态砌块对水体中硝态氮的去除率随透水率的增加呈现先增大再减小的趋势,其中骨料粒径为7~11 mm,透水率为6.6 m L/(s.cm^2)的多孔生态砌块对硝态氮的去除率可达90.3%。

In order to improve the purification ability to non-point pollution of the revetment material,the porous eco-block with high permeable rate was prepared by the aggregate cross-linking method to study the relationship of particle size and permeable rate. The surface load of denitrifying bacteria was carried out on the eco-blocks with different permeable rate by the method of biofilm formation in flowing water. On this basis,the coupling effect of water permeation rate and surface area of the porous eco-block with different aggregate size on the removal rate of nitric nitrogen in water was studied. The results show that,in the same porosity,the permeable rate of the porous block decreases when its specific surface area increases,while increasing when its aggregate size expands. The removal rate of nitric nitrogen in water decreases after increasing when the permeable rate of the porous eco-block increases,the removal rate of nitric nitrogen by the porous block can be up to 90. 3% when the aggregate size of the porous eco-block is 7 ~ 11 mm and its permeable rate is 6. 6 m L/( s·cm^2).