碳氮比对好氧颗粒污泥稳定性的影响

Influence of carbon-nitrogen ratio on the stability of aerobic granular sludge

针对好氧颗粒污泥运行过程中稳定性较差的问题,在3个C/N比条件下,通过气升式内循环反应器对好氧颗粒污泥进行培养,分析了不同时期好氧颗粒污泥的沉降性能、粒径变化、进出水水质中有机物、胞外聚合物组分及含量变化,探讨了C/N比对好氧颗粒污泥稳定性的影响。结果表明,在C/N比分别为10、15和25的条件下,均能培养出好氧颗粒污泥,C/N比为15时,好氧颗粒污泥稳定性最优,此时好氧颗粒26 d内成熟,其SVI值为16.98 mL·g^−1,颗粒粒径主要分布在0.2~0.6 mm,对COD、NH4^+-N和TP的去除率可达93%、75%和91%,松散型EPS和紧密型EPS的含量最高分别为44.97 mg·g^−1和54.20 mg·g^−1。在采用不同C/N比对好氧颗粒污泥的培养过程中,C/N比对好氧颗粒污泥稳定性有较大影响,其中松散型EPS与好氧颗粒污泥的稳定性呈正相关关系。

To explore the influence of carbon-nitrogen ratio(C/N)on the stability of aerobic granular sludge,sequencing batch airlift reactors was applied to cultivate aerobic granular sludge under three different C/N conditions,the performance of aerobic granular sludge were analyzed,including settling performance,particle size distribution,organic matter concentration as well as variations of extracellular polymeric substance(EPS)in the process of cultivation.The results showed that the aerobic granules was successfully cultivated at C/N ratios of 10,15 and 25,and the most stable ones occurred at C/N ratio of 15.They matured within 26 days,their SVI and particle size were about 16.98 mL·g^-1 and 0.2~0.6 mm,respectively.The removal rates of COD,TP were 93%,75% and 91%,respectively.Meanwhile,LB-EPS and TB-EPS were up to 44.97 mg·g^-1 and 54.20 mg·g^-1.The C/N ratio of influent had a great influence on the stability of aerobic granular sludge,and the LBEPS had a positive correlation with the stability of aerobic granular sludge.