Pseudomonas flava WD-3对人工湿地污染物的去除及Monod模型模拟

为确保寒冷地区冬季人工湿地的污水处理效果,采用从南四湖人工湿地中分离筛选出的耐低温菌Pseudomonas flava WD-3为研究对象,研究其在冬季不同梯度接种量(菌悬液的浓度为4.575×108个·m L-1)和水力停留时间时在复合垂直流人工湿地中连续3个月内的污水处理效果,采用简化的Monod动力学模型对该菌在人工湿地中对污染物的去除进行模拟并验证,并讨论了该菌的投加量和水力停留时间与污染物去除的关系.结果表明,Pseudomonas flava WD-3对污水中的有机污染物以及氮磷等营养物具有明显的去除效果.菌株的最佳投加量为6.0%,且其对污水中COD、NH3-N、TP的去除率分别介于:85.82%~87.00%、73.91%~84.18%和82.04%~85.38%,平均去除效率分别为未投加该菌的1.49、1.46、1.76倍,最佳水力停留时间为7d.简化的Monod模型对Pseudomonas flava WD-3在冬季对人工湿地中污染物去除的预测较为准确,同时,该菌的投加量和水力停留时间均与去除率呈正相关的一级反应关系.

Pollutants removal by Pseudomonas flava WD-3 and Monod model simulatio n in constructed wetland

Effect of Pseudomonas flava WD-3 on the performance of sewage treatment of an integrated vertical-flow constructed wetland in winter was investigated. Different dosages of bacteria (concentration of bacterial suspension is 4.575 × 10⁸ mL^-1) and hydraulic retention time were applied in a simplified Monod Model to simulate the kinetics of degradation of pollutants for three months continuously. Results showed that Pseudomonas flava WD-3 was effective in removing organic pollutants, nitrogen and phosphorus nutrients in wastewater. The optimal dosage of this strain was 6.0%, and the removal efficiency of COD, NH₃-N and TP were 85.82%~87.00%, 73.91%~84.18% and 82.04%~87.00%, respectively. The average removal efficiency were 1.46, 1.49 and 1.76 times those without incubation while the optimal hydraulic retention time was seven days. The simplified Monod Model was accurate in predicting the removal efficiency of pollutant by Pseudomonas flava WD-3 in IVCW system in winter. Further, the incubated bacterial dosage and hydraulic retention time are positively correlated with the removal rates.