原水输送管道生物膜的生长及其对硝化作用的影响

Biofilm Formation and Its Effect on Nitrification in Raw Water Distribution Pipeline

利用原水输送管道模拟系统,考察了管壁生物膜在自然形成过程中的微生物种群分布和生物多样性变化,探讨了原水管道的运行时间对原水中硝化作用的影响。结果表明,在管壁生物膜自然形成过程中,微生物表现出明显的群落演替现象,微生物的生长经历了适应期、对数生长期、脱落期和稳定期四个阶段,原水中的硝化作用不断趋于彻底。随着运行时间的增加,微生物多样性逐渐降低,生物系统趋于稳定。运行75 d后,NH_4^+-N浓度的变化率稳定在-45%左右;125 d后,NO_2^--N浓度的变化率稳定在-90%左右,NO_3^--N浓度的变化率稳定在40%左右。

A raw water crobial population distribution distribution pipeline simulating system was built to study the change of mi- and diversity during the natural formation of biofilm, and the influence of running time of raw water pipeline on nitrification in raw water was discussed. The results indicated that obvious microbial community succession was observed during the natural formation of the biofilm on the inner pipe wall. The growth of microorganism experienced four stages including adaptive period, expo- nential period, detachment period and stable period, and the nitrification effect in raw water tended to be thorough＇ With the increase of the running time, the microbial diversity gradually decreased and the bio- logical system tended to be stable. The change rate of ammonia nitrogen stabilized at around -45% after 75 days＇ operation, and the change rates of nitrite and nitrate stabilized at about -90% and 40% re- spectively after 125 days＇ operation.