臭氧投量对SBR系统污泥沉降性能及脱氮除磷的影响

以污水厂冬季膨胀期污泥（SVI=280 mL·g^-1）为对象，研究了臭氧投量对SBR系统污泥沉降性能及脱氮除磷效果的影响.结果表明，低浓度投加臭氧（0.085 g·g^-1，以O₃/MLSS计）20 d后，菌丝体被打断，SVI降至125 mL·g^-1，消除了污泥膨胀，且硝化、除磷效果不受影响.高浓度投加臭氧，污泥的沉降性能反而开始恶化，除磷效率也降至60%左右.进一步研究表明，PS/PN与SVI呈正相关关系（R²=0.9381），可表征污泥的沉降性能；臭氧除打断菌丝体外，还通过改变EPS的含量及组分影响着污泥的沉降性能.

Effect of Ozone Dosage on Sludge Settleability and Biological Nutrient Removal in SBR System

The effect of ozone dosage on sludge settleability and biological nutrient removal performance in a sequencing batch reactor was investigated by inoculating the bulking sludge with the SVI of 280 mL·g^-1 from a wastewater treatment plant in winter. The filamentous mycelium was interrupted, and the SVI was decreased to 125 mL·g^-1 after ozone dosage with a low concentration of 0.085 g·g^-1(O₃/MLSS) for 20 days, which indicated the disappearance of the sludge bulking. The performance of nitrification and phosphorus removal efficiency was not affected obviously. However, the sludge settleability deteriorated with a high dosage of ozone, and the phosphorus removal efficiency was decreased to around 60%. Further study showed that PS/PN had a positive correlation with SVI with the correlation coefficient of 0.9381, which can be used to characterize sludge settleability. A low ozone dosage not only interrupted the filamentous mycelium, but it also affected the content and composition of the EPS, which led to improved settleability.