中文摘要：

以序批式反应器培养的成熟好氧颗粒污泥为对象,研究沉淀高度对颗粒数、比重、污泥浓度、粒径分布及选择系数的影响.结果表明,随着沉淀高度的增加,污泥浓度在沉淀时间为30 s时由0.24 mg.L-1明显增加至6.07 mg.L-1,平均粒径从450μm增加到550μm,颗粒圆形度增加12.67%,而复杂度减小13.47%,说明粒径较大、形状较规则的颗粒沉降较快,从而更易在沉降选择过程中得以保留.根据选择压原理,结合颗粒污泥沉降实验结果引入选择系数.实验和计算结果显示,在任意沉淀高度,选择系数随粒径和密度的增大而增加.随着沉淀高度的增加,直径〉600～800μm的颗粒选择系数增加,小颗粒趋势与之相反,说明增大排水比有利于大颗粒保留而絮体被筛选出反应器,而低的排水比会使污泥颗粒化过程放缓.该研究结果可望对加速污泥颗粒化过程和提高其稳定性提供科学的理论依据和指导.

英文摘要：

Settling process of mature aerobic granules cultivated in sequencing batch reactor was investigated in this study.With the increase of settling height,the concentration of suspended solids increased from 0.24 mg·L-1 to 6.07 mg·L-1,mean size increased from 450 μm to 550 μm and roundness of granules increased by 12.67%.This indicated that big and regular granules have high settling velocity and can remain in the reactor after settling selection.A new parameter,selective coefficient is introduced based on the theory of selective pressure and settling experiments.Both experimental and simulated results showed that the selective coefficient increased with the increase of granule size and density,at any settling height.With the increase of settling height,selective coefficient of granules with radius above 600-800 μm increased,while that of smaller granules decreased.At high exchange ratio,bigger granules have higher selective coefficient and can accumulate more than smaller ones.At lower exchange ratio,the granulation process will slow down.Results of this study can provide foundation and instruction for the cultivation and stability of aerobic granular sludge reactors.