不同人工湿地基质对铅的去除效果对比

Preventive Measures and Recovery Countermeasures of Substrate Clogging in Constructed Wetlands

采用等温吸附实验研究沸石、生物陶粒、磁铁矿石、膨胀珍珠岩、砾石及石英砂这六种人工湿地基质对铅的吸附特征。结果表明:沸石、磁铁矿石和砾石对铅的吸附量均随着铅溶液浓度的增大而增大,而生物陶粒、膨胀珍珠岩及石英砂随着铅溶液浓度的增加均出现不同程度的下降;6种基质对于铅的吸附量总体趋势由大到小依次为沸石、磁铁矿石、砾石、生物陶粒、膨胀珍珠岩、石英砂;除沸石外,其余5种基质对Pb2+的去除率随着铅溶液溶度的增加,均出现不同程度的下降。因此,通过比较实验结果,确定沸石为除铅效果较理想的人工湿地基质。最后,用沸石和香蒲组建人工湿地系统,验证沸石作为基质对酸性含铅废水的处理效果,经分析实验数据表明:其出水到后期均达到《城镇污水处理厂污染物排放标准》(GB18918-2002)的排放标准。因此,确定可用沸石作为人工湿地处理酸性含铅废水的基质,其对铅的处理效果很好。

The adsorption characteristics of lead on the matrixes of six kinds of artificial wetlands such as zeolite, biological ceramsite, magnetite, expanded perlite, gravel and quartz sand were studied using isothermal adsorption experiments.The results show that： magnetite ore and gravel increased with the increase of lead concentration, while the biological ceramsite, expanded perlite and quartz ore showed different degrees with the increase of lead concentration.the lead adsorption capacity degree of six matrix is zeolite 〉 magnetite ore 〉 gravel 〉 biological ceramsite〉 expanded perlite 〉 quartz; with the increasing concentration of lead standard solution, except zeolite, the other five matrix has different degree decrease removal rate. Therdore, through comparative experiments, it was determined that zeolite is the better lead removal matrix of artificial wetland. Finally, the artificial wetland system with zeolite and bulrushes, prove that zeolite matrix has better lead acid wastewater treatment effect. The analysis of experimental data showed that the effluent reached the urban sewage treatment plant emissions standards （GB18918-2002）emission standards. Therefore, it was determined that zeolite can be used as a substrate for the treatment of acidic lead -containing waste water in constructed wetlands and its effect on lead treatment is very good.