低温下AHLs对多级A/O工艺中好氧生物膜特性的影响

针对低温条件下多级A/O工艺出水氨氮容易超标问题,进行外源添加酰基高丝氨酸内酯类信号分子(AHLs)对低温下多级A/O工艺好氧段生物膜特性的影响研究.结果 表明:添加100nmol/L的己酰基高丝氨酸内酯(C6-HSL)后生物膜硝化效率提高了22.34％,十二烷酰基高丝氨酸内酯(C12-HSL)则将生物附着量提高了24...

Effects of AHLs at low temperature on the characteristics of mature biofilms in aerobic zone of multi-stage A/O technology

Aiming at the problem that the ammonia nitrogen in the effluent of the multi-stage A/O technology is likely to exceed the standard under low temperature conditions, the effect of exogenous addition of acyl homoserine lactone signal molecules (AHLs) on the characteristics of the biofilm in the aerobic zone of the multi-stage A/O technology at low temperature was studied. Results showed that the addition of 100nmol/L hexanoyl homoserine lactone (C6-HSL) increased the biofilm nitrification efficiency by 22.34%, and lauryl homoserine lactone (C12-HSL) increased the amount of attachment biomass by 24.47%, both C6-HSL and C12-HSL had long-term effects on the nitrification efficiency and biological adhesion of biofilm. This was because C6-HSL can increase the aerobic biofilm nitrification activity by 17.56% at low temperature, while C12-HSL could increase the content of protein (PN) in EPS by 67.37%. In addition, both C6-HSL and C12-HSL could promote the endogenous release of the same signal, thus having a long-term positive impact on the nitrification activity and adhesion performance of biofilm. The high-throughput sequencing analysis showed that C6-HSL can increase the abundance of Nitrosomonas, and thus enhancing the nitrification activity of biofilm in R2; while the addition of C12-HSL had a greater impact on the abundance of Rhodobacter, which was an important reason for the increase of PN content in EPS of R5 biofilm.