交替式A~2/O系统碳源量对去除氮磷途径的影响

采用市政污水研究进水碳源含量不同时交替式A2/O工艺去除氮磷的途径以及效果.调控进水COD浓度分别在150、200、300、400 mg.L-1左右,氮磷浓度不变,跟踪厌氧池与缺氧池内NO3--N与总磷(TP)的变化规律.实验结果显示,几种进水水质下,系统都具有优良的除磷脱氮性能;进水COD在300、400 mg.L-1时,缺氧池内NO3--N浓度始终低于1 mg.L-1,而TP浓度由于推流作用逐渐上升,系统主要通过反硝化异养菌利用外碳源进行反硝化作用去除NO3--N;进水COD在150、200 mg.L-1时,缺氧池内TP浓度一直较低,有反硝化聚磷现象,表明交替式A2/O系统内存在专性好氧聚磷菌与反硝化聚磷菌.

Performance and approach to nutrient removal alternate A~2/O process at various carbon source levels

Performance and approach to nutrient removal in alternate A2/O process were investigated using municipal wastewater.Four influent COD values were designed,that was 150,200,300 and 400 mg·L-1,respectively,while the nitrogen and phosphorus concentrations were changeless.And the variations of nitrate and total phosphorus(TP) were studied in anoxic and anaerobic tanks.The results showed that the system has good performance on nutrient removal at various COD concentration levels.In anoxic tank,when influent COD was 300 and 400 mg·L-1,nitrate concentration was always below 1 mg·L-1,while TP concentration rose gradually due to influent,indicating the nitrate was removed mostly by ordinary heterotrophic organisms,using influent carbon source.When influent COD was 150 and 200 mg·L-1,TP in anoxic tank was always low,demonstrating the phenomenon of denitrifying phosphorus removal.This finding suggests aerobic polyphosphate-accumulating organisms(PAOs) and denitrifying PAOs exist together in alternate A2/O system.