太阳能曝气下生物炭漂浮湿地的净化能力

Effects of Solar Aeration on Purification Capacity of Floating Constructed Wetlands with Biochar

构建了以沙子和生物炭混合为基质的漂浮人工湿地,并利用光伏板发电驱动曝气,研究曝气和生物炭对漂浮人工湿地溶解氧和净化能力的影响及机理。结果表明,曝气30 min时,漂浮人工湿地基质外的DO含量稳定在7 mg/L;曝气10 min和90 min后漂浮人工湿地基质中的DO含量分别为2.0 mg/L和2.7~3.3 mg/L。停止曝气后漂浮人工湿地外的DO下降,当停止曝气240 min后,DO含量下降到1.8 mg/L,恢复到曝气前的水平。漂浮人工湿地加入生物炭对NH_4^+-N、NO_3^--N、TN、TP和COD的去除率分别提高了31%、7%、70%、5%和7%。曝气后,漂浮人工湿地对NH_4^+-N、TN、TP和COD的去除率分别提高了44%、176%、6%和9%。曝气能有效提高漂浮人工湿地DO含量,可使DO含量从0.2 mg/L增加到7 mg/L,从而提高人工湿地的净化能力。光伏板发电驱动曝气和生物炭有利于提高漂浮人工湿地的净化能力。

The effect of aeration and biochar on capacity and mechanism of floating constructed wetland was studied,based on floating constructed wetland built with mixture of sand and biochar as substrate,which was aerated by photovoltaic power.Results showed that the DO content beside floating constructed wetland was stable at 7 mg/L after aeration for 30 min.After aeration for 10 min and 90 min,the DO content in the floating constructed wetland was 2 mg/L and 2.7～3.3 mg/L,respectively.After stopping aeration,the DO content beside the floating constructed wetland began to decrease.Taken stopping aeration240 min for example,the DO content decreased to 1.8 mg/L,which returned to the level before aeration.When addition of biochar into floating constructed wetland,the removal rate of NH4＋-N,NO3--N,TN,TP and COD increased by 31%,7%,70%,5%and 7%,respectively.After aeration of floating constructed wetland,removal efficiency of NH4＋-N,TN,TP and COD increased by 44%,176%,6%and 9%,respectively.Aeration can effectively increase the DO content in floating constructed wetlands,increasing the DO content from 0.2 mg/L to 7 mg/L,which result in enhancing capacity of constructed wetland.The aeration driven by photovoltaic panels and biochar are beneficial to improve the purification capacity of floating constructed wetlands.