人工湿地不同基质和粒径对污水净化效果的比较

为研究人工湿地基质类型和粒径对水质净化效率的影响,选择了1~2、2~4、4~8 mm的沸石,2~4、4~8、8~16mm的砾石和2~4、3~5、6~8 mm的无烟煤基质,在无植物人工实验柱中开展单一基质的水质净化实验.结果表明,相同类型不同粒径的基质对COD、TN、TP的去除效果不同.4~8 mm沸石和砾石、6~8 mm无烟煤对COD的去除率最高,分别为53.74%、60.76%、62.93%;人工实验柱中氮素的去除以反硝化作用为主,粒径对TN去除效果的影响表现为小粒径更优;砾石和无烟煤的TP去除率也表现为小粒径更高,但沸石的TP去除率随着粒径的增大而增大.基质类型对COD、TP、TN的去除效果也存在差异.无烟煤对COD、TP、TN均有较好的去除效果,平均去除率在60%以上;沸石对TN的去除效果最好,TP去除率不高;砾石对COD有较高的去除率,对TP的去除效果一般.

Effects of Different Substrates and Particle Sizes on Wastewater Purification

Choosing suitable substrate is key to improving the efficiency of wetland decontamination. However, little is known about the effect of particle size. In order to study the effect of substrate type and size on COD, TN, and TP removal from sewage, 1-2, 2-4, and 4-8 mm zeolite, 2-4, 4-8, and 8-16 mm gravel, and 2-4, 3-5, and 6-8 mm anthracite were selected for establishment of the constructed system of experimental media with three replications. Results showed that removal efficiency of COD, TN, and TP varied with different particle sizes of the same material. The greatest COD removal was achieved with 4-8 mm zeolite and gravel and 6-8 mm anthracite, with removal rates of 53.74%, 60.76%, and 62.93%, respectively. Denitrification is the main pattern of nitrogen removal in the artificial test column; results show that smaller particle size is more effective for removal of TN. The removal rate of TP is also higher with smaller sizes of gravel and anthracite, but the opposite pattern occurred with zeolite. The removal of COD, TP, and TN also varied by substrate type. Anthracite led to good removal of COD, TP, and TN. Zeolite was most effective for removal of TN but had lower removal of TP. Gravel has high removal rate for COD, and has a general removal effect on TP.