摘要

       本研究调查了消毒方法，包括氯化、紫外线 (UV) 照射和连续紫外线/氯化处理对抗生素抗性基因 (ARG) 的灭活。检测了市政污水处理厂 (MWTP) 流出物中的 ARG，包括 sul1、tetX、tetG、intI1 和 16S rRNA 基因。结果表明 ARG 的去除与氯剂量（p = 0.007–0.014，n = 6）以及接触时间（p = 0.0001，n = 10）之间呈正相关。较大的游离氯 (FC) 剂量导致所有基因的去除率更高，并且在 FC 剂量为 30 mg L− 1 时可以实现最大去除率（1.30–1.49 log）。 ARGs 去除的转化动力学数据（log C0 / C ) 遵循二级反应动力学模型，分别具有 FC 剂量 (R2 = 0.6829–0.9999) 和接触时间 (R2 = 0.7353–8634)。发现较高的氨氮 (NH3–N) 浓度会导致相同氯剂量下 ARG 的去除率较低。当应用的 Cl2:NH3-N 比率超过 7.6:1 时，ARG 显着减少（1.20-1.49 log）。通过使用单次紫外线照射，tetX 和 16Ss rRNA 基因的对数去除值分别为 0.58 和 0.60，而其他基因在 249.5 mJ cm-2 的通量下为 0.36-0.40，观察到其效果不如氯化。通过连续的紫外线/氯化处理，在不同的操作参数下观察到目标基因的 0.006 至 0.31 log 协同值。

       This study investigated disinfection methods including chlorination, ultraviolet (UV) irradiation and sequential UV/chlorination treatment on the inactivation of antibiotic resistance genes (ARGs). ARGs including sul1, tetX, tetG, intI1, and 16S rRNA genes in municipal wastewater treatment plant (MWTP) effluent were examined. The results indicated a positive correlation between the removal of ARGs and chlorine dosage (p = 0.007–0.014, n = 6),as well as contact time (p = 0.0001, n = 10). Greater free chlorine (FC) dosage leads to higher removal for all the genes and the maximum removal (1.30–1.49 logs) could be achieved at FC dosage of 30 mg L− 1. The transformation kinetic data for ARGs removal (log C0 / C) followed the second-order reaction kinetic model with FC dosage (R2 = 0.6829–0.9999) and contact time (R2 = 0.7353–8634), respectively. Higher ammonia nitrogen (NH3–N) concentration was found to lead to lower removal of ARGs at the same chlorine dosage. When the applied Cl2:NH3–N ratio was over 7.6:1, a significant reduction of ARGs (1.20–1.49 logs) was achieved. By using single UV irradiation, the log removal values of tetX and 16Ss rRNA genes were 0.58 and 0.60, respectively, while other genes were 0.36–0.40 at a fluence of 249.5 mJ cm− 2, which was observed to be less effective than chlorination. With sequential UV/chlorination treatment, 0.006 to 0.31 log synergy values of target genes were observed under different operation parameters.

https://www.sciencedirect.com/science/article/abs/pii/S0048969715000315