组合人工湿地对化工园区尾水COD的去除及其模拟

采用组合人工湿地中试试验对工业园区污水厂尾水进行处理,研究了3种不同的水力负荷(10cm/d,20cm/d和25cm/d)下COD的去除,并用一级动力学模型对组合人工湿地及其各个湿地单元的COD的去除进行了模拟。结果表明组合人工湿地对COD的去除受水力负荷影响有限,去除率基本都在60%以上,系统出水COD浓度在40mg/L以下,并且夏季的去除效果最佳。对数学模拟的结果进行分析,发现一、二级潜流湿地对COD去除贡献较大,另外组合人工湿地系统对COD的去除效果也优于单个的湿地。系统最终出水中的COD模拟结果和实测值相接近,说明基于一级动力学模型的组合人工湿地数学模拟对实际运行有指导意义。

Removal and Simulation of COD in Industrial Park Tail-wastewater Using Hybrid Constructed Wetland

In this paper,the tail-wastewater of industrial park was treated by using a pilot-scale hybrid constructed wetland.The removal of COD at three different hydraulic loading rate（HLR = 10cm /d,20cm /d and 25cm /d） were studied,and the first-order kinetic model was used to simulate COD removal in the hybrid constructed wetland and each unit wetland.Results showed that HLR had limited effect on the removal of COD in hybrid constructed wetland.Basically,the removal efficiency of COD was above 60%,and the concentration of COD in effluent was lower than 40mg /L.The system performed the best in summer.The result of mathematic model showed that primary and second subsurface wetlands contributed to COD removal significantly,and the hybrid wetland system tended to perfom better than individual wetland.The simulating COD concentrations were close to the measured values,which indicated that the first-order kinetic model could be applied in guiding the operation of the hybrid constructed wetland.