基于六偏磷酸钠-Fe^(2+)的铁盐脱氮反应器运行性能及微生物学特征研究

Operation performance and microbiological characteristics of ferrous ion-dependent nitrate removal reactor based on sodium hexametaphosphate-Fe^(2+)

以实验室高效反硝化反应器中的反硝化污泥作为接种污泥,启动自养型六偏磷酸钠-Fe^(2+)脱氮反应器,试验采用模拟废水通过88 d的不间断运行,研究了铁盐脱氮工艺的脱氮效能及其微生物学特性。结果表明,当反应器硝态氮容积负荷为0.42 kg/(m^(3)·d)时,最高稳定氮去除负荷为0.41 kg/(m^(3)·d);当Fe^(2+)容积负荷为4.92 kg/(m^(3)·d)时,最大铁去除负荷为2.77 kg/(m^(3)·d)。反应器稳定运行时硝态氮、Fe^(2+)的去除率分别达94.6%、52.6%,最佳效能可维持28 d。反应器运行到第82天时,颗粒污泥由黄色变为灰褐色,颗粒解体,污泥比活性逐渐升高,比反硝化活性由0.71 mg[N]/(g[VSS]·h)升高到2.3 mg[N]/(g[VSS]·h),同比上升224%;比铁氧化活性由7.3 mg[Fe]/(g[VSS]·h)升高到15 mg[Fe]/(g[VSS]·h),同比上升105%。六偏磷酸钠-Fe^(2+)脱氮作为一种新型自养反硝化技术,不仅增强了活细菌的生物活性和反硝化活性,还延长了铁盐脱氮污泥反硝化的高效期。

The denitrification sludge from high-efficiency denitrification reactor in laboratory was utilized as inoculation sludge to start autotrophic sodium hexametaphosphate-Fe^(2+)denitrification reactor.The nitrogen removal efficiency and microbiological characteristics of the iron salt nitrogen removal process was investigated through a 88-day continuous operation using simulated wastewater.The results showed that,at a nitrate nitrogen volumetric load of 0.42 kg/(m^(3)·d),the maximum stable nitrogen removal load was 0.41 kg/(m^(3)·d);similarly,at a Fe^(2+)volumetric load of 4.92 kg/(m^(3)·d),the maximum iron removal load was 2.77 kg/(m^(3)·d).The reactor exhibited a nitrate and Fe^(2+)removal rates of 94.6% and 52.6% respectively during stable operation,maintaining optimal performance for 28 days.By the 82_(th) day of the operation,the color of granular sludge changed from yellow to grayish brown,accompanied by particle disintegration.The specific activity of the sludge gradually increased,the specific denitrification activity increased from 0.71 to 2.3 mg[N]/(g[VSS]·h),showed a significant increase of 224%,and the specifica iron oxidation activity increased from 7.3 to 15 mg[Fe]/(g[VSS]·h),showed a notable increase of 105%.As a new autotrophic denitrification technology,sodium hexametaphosphate-Fe^(2+)nitrogen removal technology not only enhances the biological activity and denitrification activity of living bacteria,but also prolongs the efficient denitrification period of ferric denitrized sludge.