厌氧消化联合工艺去除养殖废水中TRGs的探究

The Removal of TRGs from Farm Wastewater by Anaerobic Digestion Combined Process

有效去除奶牛养殖废水中四环素类抗性基因(Tetracycline antibiotic resistancegenes,TRGs),有助于进一步控制抗生素抗性在环境中的传播扩散。采用厌氧消化-超声-吸附联合处理工艺,分析其对奶牛养殖废水中TRGs的去除效率。结果表明,经厌氧消化后,奶牛养殖废水中的tetQ和tetG的绝对丰度上升,tetC、tetO、tetT和tetX的绝对丰度下降,总TRGs绝对丰度降低28.61%。超声处理可有效降低消化液中TRGs的丰度,且胞外TRGs(extracellular TRGs,eTRGs)的丰度占比增高;其中,在声能密度为1.5 W/mL和时间为40 min的超声条件下,对TRGs的去除率达到最大为83.29%。生物炭吸附处理能有效去除超声处理液中的TRGs和eTRGs,去除率分别为45.29%和71.09%。厌氧消化-超声-吸附联合处理工艺对奶牛养殖废水中TRGs的总去除率可达99.32%,表明此联合处理工艺能较大程度去除奶牛养殖废水中的TRGs,有效降低其向周边环境传播扩散的风险。

Effective removal of tetracycline antibiotic resistance genes(TRGs)in dairy farm wastewater is helpful to further control the spread of antibiotic resistance in the environment.In this study,anaerobic digestion combined with an ultrasonic-adsorption treatment process was used to analyze the removal efficiency of TRGs in cow manure water.The results showed that after anaerobic digestion,the absolute abundances of tetQ and tetG in cow manure water increased,the absolute abundances of tetC,tetO,tetT,and tetX decreased,and the absolute abundance of total TRGs decreased by 28.61%.Ultrasonic treatment can effectively reduce the abundance of TRGs in the digestive juice,and the abundance of extracellular TRGs(eTRGs)increases.The removal rate of TRGs reached a maximum of 83.29%.Biochar adsorption treatment can effectively remove TRGs and eTRGs in the ultrasonic treatment solution,and the removal rates are 45.29%and 71.09%,respectively.The total removal rate of TRGs in cow manure water by anaerobic digestion combined with ultrasonic-adsorption treatment process can reach 99.32%,indicating that this combined process can remove TRGs in cow manure water to a greater extent and effectively reduce the risk of its spread to the surrounding environment.