BPAC-UF对二级出水中抗生素抗性基因的去除及膜污染缓解机制

采用生物粉末活性炭(BPAC)-超滤(UF)组合工艺去除控制二级出水中抗生素抗性基因(ARGs)，并对ARGs的去除和BPAC缓解膜污染机制进行了探讨。结果表明：与直接超滤工艺相比，组合工艺对水中四环素类抗性基因(tetA、tetW)、磺胺类抗性基因(sul Ⅰ、sul Ⅱ)以及溶解性有机碳(DOC)的去除效果均有较大的改善，这主要是由于BPAC对ARGs的吸附降解作用所致；水中16S rDNA、int Ⅰ 1和DOC含量与不同种类ARGs浓度具有显著相关性，强化上述指标的去除可有效促进ARGs的削减；在BPAC投加量较低时，组合工艺的膜比通量较直接UF有所提高，膜污染状况明显改善；直接UF时，膜污染状况与滤饼层过滤模型的拟合度最好，而组合工艺的膜污染状况与标准膜孔堵塞模型和滤饼层过滤模型拟合度均较好。BPAC-UF组合工艺是一种较好的去除ARGs的工艺。

Antibiotic resistance genes removal from secondary effluent by BPAC-UF combined process and membrane fouling control mechanisms

The combined process of biological powder activated carbon (BPAC) and ultrafiltration (UF) was used to remove antibiotic resistance genes (ARGs) in secondary effluent, and the mechanisms of ARGs removal and membrane fouling control were also investigated. The results showed that in comparison with UF, BPAC-UF process could greatly improve the removal of tetracycline resistance genes (tetA, tetW), sulfonamide resistance genes (sulI, sulII), and dissolved organic carbon (DOC), owing to the combined effects of adsorption and degradation effect towards ARGs. The contents of 16S rDNA, intI1 and DOC were positively correlated with the total concentrations of different ARGs, and the ARGs removal could benefit from the enhanced removal of 16S rDNA, intI1 and DOC accordingly. At low BPAC dosage, the membrane specific flux of BPAC-UF was higher than that of direct ultrafiltration, and the corresponding membrane fouling was obviously alleviated. The cake formation model was better to describe the membrane fouling performance of direct UF. Comparatively, both the internal pore blocking model and the cake formation model were better to fit the membrane behaviors of BPAC-UF process. BPAC-UF process is promising and potentially valuable for the ARGs removal from secondary effluent.