摘要
[Objective] This study aimed to make use of the limited filamentous sludge bulking characteristics to purify water quality and save energy. [Method] The effects of dissolved oxygen （DO） on sludge bulking were explored by changing the DO con- centration in the aerobiotic pool of NO system from the low load （0.25 kg COD/（kg MLSS.d）） and the medium to high load （0.55 kgCOD/（kg MLSSod））. [Result] In the NO activated sludge system, when the sludge load was 0.25 kg COD/（kg MLSS.d）, DO=1.5 mg/L, the sludge index was at around 250, while when the sludge load- ing was 0.55 kg COD/（kg MLSS.d）, DO=1.5 mg/L, the sludge index was close to 300, occurring the limited filamentous bulking. The bulked sludge still showed high removal rates to COD, SS, nitrogen and phosphorus. [Conclusion] It could improve the oxygen transfer rate and reduce the aeration rate at low DO conditions to achieve energy-saving.
[目的]利用污泥微膨胀的特性来净化水质、节约能源。[方法]分别从低负荷(0.25 kgCOD/(kgMLSS·d))和中高负荷(0.55kgCOD/(kgMLSS·d))两个点出发,改变A/O系统好氧池中的溶解氧浓度,来考察溶解氧对污泥膨胀的影响。[结果]在A/O活性污泥系统中,当污泥负荷为0.25 kgCOD/(kgMLSS·d)、DO=1.5 mg/L时,污泥指数在250左右,污泥负荷为0.55 kgCOD/(kgMLSS·d)、DO=1.5 mg/L时,污泥指数接近300,系统发生了微膨胀现象。污泥微膨胀时系统对COD、SS、氮、磷等的去除率依然较高。[结论]在低溶解氧条件下可以提高氧转移速率,减少曝气量,具有节能的效果。
基金
Supported by the National Natural Science Foundation of China(51208068)~~
