臭氧投量对SBR系统污泥沉降性能及脱氮除磷的影响

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

以污水厂冬季膨胀期污泥(SVI=280 m L·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 m L·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(R^(2)=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.

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 m L·g^(-1)from a wastewater treatment plant in winter.The filamentous mycelium was interrupted,and the SVI was decreased to 125 m L·g^(-1)after ozone dosage with a low concentration of 0.085g·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 0.938 1,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.