活性污泥SBR系统对四环素耐药菌和总四环素的去除特性

Study of removal characteristic on tetracycline and tetracycline resistant bacteria in SBR

通过模拟运行SBR工艺,比较不同四环素进水浓度、运行周期以及氧环境条件对四环素耐药菌及痕量四环素的去除特性.结果表明,痕量四环素的存在会对活性污泥中微生物耐药性产生影响,SBR进水四环素浓度为250μg.L-1时活性污泥中的微生物会逐步变成耐药微生物,而进水中不含四环素时,耐药的微生物会逐步变成非耐药微生物.总四环素的去除效果在好氧条件下周期为12 h时最好,达到90%以上.好氧条件下周期为8 h时每克污泥增加的四环素耐药菌数最多,约为2.89×109CFU.g-1;好氧条件下周期为20 h时为最少,约为1.0×108CFU.g-1,有利于缓解四环素耐药菌的产生.

In this work, the removal characteristics of tetracycline and tetracycline resistant bacteria through operating SBR were compared with different concentrations of tetracycline, operation cycles and oxygen environmental conditions. The results show that the existence of trace tetracycline has great impact on the resistance of microorganisms in activated sludge. Some microorganisms in the actived sludge turned gradually into resistant microorganisms when the concentration of influent tetracycline was 250 μg. L-1. When the influent did not contain tetracycline, the resistant microorganisms gradually became non-resistant. Total tetracycline removal rate in aerobic condition and 12 h cycle is the highest, up to 90%. In aerobic condition and h cycle, the increase of tetracycline resistant bacteria number per gram sludge was the largest, about2.89 × 10^9 CFU.g-1. In aerobic condition and 20 h cycle, it was about 1.0 × 10^8 CFU. g-1 ,and was the lowest. This is the beneficial in inhibiting the production of tetracycline resistant bacteria.