碳氮比对移动床生物膜反应器处理海水养殖废水性能的影响

本文研究碳氮(C/N)比变化对移动床生物膜反应器(MBBR)处理海水养殖废水性能的影响.结果表明,当C/N比从7:1降至3:1,出水COD浓度无明显变化,平均去除率保持在90％以上.C/N比的变化对脱氮过程有较大影响,当C/N比从7:1降低至3:1,NH+4-N去除率由89.51％±1.24％增至92.70％±1.08...

Effect of C/N Ratio on the Performace of Moving Bed Biofilm Reactor Treating Mariculture Wastewater

The effect of a Moving Bed Biofilm Reactor(MBBR)on the treatment of mariculture wastewater were evaluated at different C/N ratios.The results showed that the effluent COD concentration had no significant variation with the decrease of C/N ratio from 7∶1 to 3∶1,and the average removal efficiency remained above 90%.The removal efficiency of NH⁺₄-N increased from 89.51%±1.24%to 92.70%±1.08%with the C/N ratio decreased from 7∶1 to 3∶1.The effluent NO^-₂-N concentration decreased from(4.84±0.50)mg/L to 0 mg/L,and the effluent NO^-₃-N concentration increased from(0.47±0.29)mg/L to(8.12±0.25)mg/L.With the decrease of C/N ratio,the specific oxygen-utilizing rate,specific nitrate-reducing rate,specific nitrite-reducing rate and microbial enzymatic activity related to denitrification declined,and the specific ammonia-oxidizing rate,specific nitrite-oxidizing rate and microbial enzymatic activity related to nitrification increased.The polysaccharide(PS)of loosely-bound extracellular polymeric substances(LB-EPS)and tightly-bound extracellular polymeric substabces(TB-EPS)decreased with the decrease of C/N ratio,indicating that PS could be utilized by microorganisms under low COD concentration.High throughput sequencing indicated that the richness and diversity of microbial community reduced.The relative abundance of nitrifying genera(Nitrosomonas and Nitrospira)and denitrifying genera(Azoarcus,Comamonas,Hyphomicrobium,Paracoccus,Thauera,Devosia,Pseudomonas and Rhodanobacter)changed,which could further affect the nitrogen removal performance of MBBR.