【摘要】 以去除海水循环水养殖系统中硝酸盐（NO₃^--N）为目的,通过接种好氧反硝化细菌的方式构建海水好氧反硝化反应器,对其反硝化脱氮性能和动力学特征展开研究。研究结果显示,好氧反硝化反应器完成挂膜需要15 d。在有氧条件下,反应器对NO₃^--N浓度为30～150 mg·L-1海水具有良好的反硝化性能,NO₃^--N的去除率达到90%以上。批次实验结果显示:好氧反硝化过程呈现阶段性,NO₃^--N在整个过程中可被高效去除;NO₂^--N积累最大值随初始NO₃^--N浓度的增大而增大,且初始NO₃^--N浓度越高,NO₂^--N完全去除所需时间越长。采用Monod方程的微分方程模型,能够很好地拟合反硝化过程中NO₃^--N、NO₂^--N的变化趋势。该好氧反硝化反应器具有良好的脱氮性能,为解决循环水养殖系统NO₃^--N积累问题提供了新的思路。更多还原

【Abstract】 Nitrate accumulation is an important issue in the recirculating aquaculture due to the hard occurrence of denitrification in aerobic conditions of recirculating aquaculture system. In this study, an aerobic denitrification bioreactor was set up through inoculation of aerobic denitrifying bacteria, and its performance and kinetic property of nitrate removal from the synthetic aquaculture wastewater were evaluated. The results showed that it took 15 days to form biofilm in this aerobic denitrification bioreactor. A good denitrification effect occurred at aerobic conditions when the influent NO₃^--N concentration was in the range from 30 to 150 mg·L-1, and the nitrate removal rate was greater than 90%. Batch experiment was conducted to investigate the variations of nitrate, nitrite during a denitrification cycle. Obvious stages appeared in this aerobic denitrification process, and high nitrate removal efficiency was maintained. The nitrite accumulated at the beginning and then decreasing to zero. The maximum accumulating concentration of NO₂^--N increased with the increment of the initial nitrate NO₃^--N concentration. The higher the initial nitrate NO₃^--N concentration was, the longer duration for complete NO₂^--N removal occurred. Variations of nitrate and nitrite during the denitrification process can be well described by a differential form of Monod model. Our research can provide a scientific and theoretical basis for applying aerobic denitrification technology to solve the nitrate accumulation problem in the recirculating aquaculture system.更多还原