固定反硝化菌强化人工湿地处理低污染水研究

将固定反硝化菌Pseudomonas stutzeri(以聚乙烯醇、海藻酸钠为材料包埋固定)投加至人工湿地不同位置,进行低污染水模拟脱氮实验,以探究固定反硝化菌的最佳投加位置;采用高通量测序技术分析各系统微生物组成,并考察最优系统在低温下的脱氮效果。结果表明,上层投加固定反硝化菌对湿地脱氮的强化效果最佳,TN与NO_3~--N去除率分别为60.31%与64.98%;微生物多样性指数显示,投加固定反硝化菌虽降低了系统微生物丰富度,但各处理系统内主要微生物物种差异不大,Proteobacteria(变形菌门)丰度最高,投加固定反硝化菌系统中Nitrospira(硝化螺旋菌门)比例增大,有利于脱氮效果的提高。在15℃条件下,上层投加固定反硝化菌系统的TN与NO_3~--N去除率分别为50.86%与55.06%,高于空白湿地系统(TN与NO_3~--N去除率为24.81%与27.53%)。

Performance of immobilized denitrifying bacteria in constructed wetland for slightly-polluted water treatment

Denitrifying bacteria Pseudomonas stutzeri isolated from lab were fixed with PVA and SA and were added to dosing positions(up-per, lower, upper and lower)to simulate the release of the nitrate-rich source in low pollution water, aiming to determine the optimal dosing position.The reasons of enhanced nitrogen removal in microbial community diversity were analyzed by using high-throughput sequencing technology, and the effect of strengthening efficiency at low temperature was investigated. Results showed that the system dosing in upper layer got the best performance, and the removal rates of total nitrogen and nitrate were 60.31%and 64.98%, respectively. The results of mi-crobial diversity index of each system showed that the microbial species diversity in the control system was higher than othes. But overall, there was little difference between the four systems, and the most abundant phylum was Proteobacteria in each system. And the increased percentage of Nitrospirain dosing systems was conducive to improve the nitrogen removal. The results showed that the removal rates of total nitrogen and nitrate in the system dosing in upper layer were 50.86% and 55.06%, respectively, while that in the control system were 24.81%and 27.53%at 15℃.