Ni2+对好氧颗粒污泥系统性能的影响

以城镇污水处理厂A²/O工艺的回流污泥作为接种污泥，在序批式反应器（SBR）中培养好氧颗粒污泥（AGS），探究Ni²⁺对AGS系统的影响.结果表明：在25℃的条件下，50d左右培养出成熟的AGS，其形态多呈球状或椭球状，外表分布着少量丝状菌，颗粒污泥粒径主要在2~4mm，MLSS达6000mg/L，SVI维持在40~50mL/g.将Ni²⁺作用于培养出的成熟AGS，Ni²⁺在0~2mg/L的浓度范围内会提高AGS的稳定性，使MLSS上升，SVI降低；同时会促进AGS分泌胞外多聚物（EPS），EPS组成成分中的蛋白质（PN）明显多于多糖（PS）；Ni²⁺对好氧颗粒污泥去除总氮（TN）的抑制程度要大于COD，最终COD去除率可维持在95%以上，TN去除率可维持在70%以上.

Effect of Ni2+ on the performance of aerobic granular sludge system

The impact of Ni²⁺ on the aerobic granular sludge (AGS) system was explored by inoculating the return sludge from A²/O process of a municipal wastewater treatment plant in sequencing batch reactor (SBR). The mature AGS cultured at 25℃ for about 50 days had a morphology of sphere or ellipsoid with a small number of filamentous bacteria on the surface, and a particle size of 2~4mm. The AGS system keeps a mixed liquid suspended solids (MLSS) of 6000mg/L and sludge volume index (SVI) at 40~50mL/g. Ni²⁺ in the concentration range of 0~2mg/L will improve the stability of AGS, increase MLSS, and decrease SVI. Meanwhile, the extracellular polymeric substances (EPS) in AGS increased with the addition of Ni²⁺and contained significantly more protein (PN) than polysaccharide (PS). The inhibition of Ni²⁺ on removal of total nitrogen (TN) by AGS was greater than that of chemical oxygen demand (COD). Finally, the removal rate of COD and TN could be maintained above 95% and 70%, respectively.