解体好氧颗粒污泥修复

Remediation of disintegrated aerobic granules

考察了加入新的活性污泥使解体好氧颗粒污泥完成修复的可行性.解体好氧颗粒污泥对新加入的活性污泥进行吸附,在各种选择压力特别是水力剪切力作用下和原有颗粒污泥形成一个有机整体.大约3周时间,解体颗粒污泥被完全修复.扫描电镜观察发现,被修复后的颗粒污泥呈现非常规则的结构,微生物相十分致密.在解体颗粒污泥逐渐被修复的过程中,颗粒平均粒径仅从最初的2.8mm增至2.9mm,说明活性污泥在颗粒污泥上的附着主要发生在颗粒的空穴.而颗粒污泥的沉降性能和强度都得到了极大的改善,颗粒沉降速率和完整性系数分别由最初的72m/h和56.8%提高到110m/h和65.8%.新加入的活性污泥除了部分用于修复解体颗粒污泥,其余在选择压力等的作用下形成了新的好氧颗粒污泥.

The feasibility of adding fresh activated sludge for stimulating remediation of disintegrated aerobic granules was evaluated. Fresh activated sludge was gradually adsorbed into disintegrated aerobic granules. These adsorbed activated sludge then combined together with aerobic granules affected by several selection pressures,especially by hydrodynamic shear force. Disintegrated aerobic granules were fully remedied after about 3 weeks. Remedied granules exhibited regular and compact structure. With the gradual remediation of disintegrated aerobic granules,mean granule size was slightly increased from 2.8 mm to 2.9 mm,which indicated that the primary adsorption occurred within the cavities of aerobic granules. Granule settleability and strength were both improved profoundly after remediation. Granule settling velocity and integrity coefficient were changed from 72 m/h and 56.8% to 110 m/h and 65.8%,respectively. Besides the activated sludge used for remediation,the rest formed fresh aerobic granules affected by selection pressure finally.