基于Hydrus-1D软件的混合黄土滤料渗滤性能的模拟研究及优化

Simulation Study and Optimization of Percolation Performance of Mixed Loess Filter Media Based on Hydrus-1D Software

以西北地区特有的黄土作为主要过滤材料,利用Design-Expert软件优化滤料配制比,以提高黄土混合滤料的渗滤性能和污染物去除效率。实验分别以石英砂、磁铁矿和无烟煤与黄土按照5∶5、6∶4、7∶3、8∶2、9∶1、1∶0体积比混合(16组),按照30 cm和40 cm的厚度填充至反应器。实验测得混合黄土滤料的渗透系数最大可达2.38×10^(-5) m/s,COD去除率最大可达95.68%。以渗透系数为基础数据,以COD、TN、TP、电导率为目标函数,运用Design-Expert软件优化滤料配制比。优化后的实验结果表明:混合黄土滤料的体积比为V黄土∶V石英砂∶V无烟煤∶V磁铁矿=50∶34∶4∶12时,雨水处理水水质稳定,可达回用标准,且模拟结果安全性较高。

Using the unique loess in the northwest of China as the main filter material,the Design-Expert software is used to optimize the filter material preparation ratio to improve the percolation performance and pollutant removal efficiency of the loess mixed filter material.The experiment was carried out by mixing quartz sand,magnetite and anthracite with loess in a volume ratio of 5∶5,6∶4,7∶3,8∶2,9∶1,1∶0(16 groups),with 30 cm and 40 cm thickness filling to the reactor.The experimental results show that the permeability coefficient of the mixed loess filter material can reach up to 2.38×10^(-5) m/s,and the COD removal rate can reach up to 95.68%.Based on the permeability coefficient,taking the COD,TN,TP and conductivity as the objective functions,the Design-Expert software is used to optimize the filter material preparation ratio.The optimized experimental results show that the volume ratio of mixed loess filter material is Vloess∶Vquartzsand∶Vanthracite∶Vmagnetite=50∶34∶4∶12,the quality of rainwater treatment water is stable to the standard of reuse and the simulation results are safer.