pH对污泥厌氧消化过程中抗生素降解迁移的影响

Effects of pH on antibiotics degradation and migration during anaerobic sludge digestion

抗生素作为一种新型污染物,可随着城市污水厂中污泥的处理处置单元最终进入环境中,对人类健康造成潜在威胁.以城市污水厂的剩余污泥为研究对象,考察在不同初始p H(p H=5.5、6.5、7.5、8.5、9.5、10.5)条件下,12种抗生素在污泥厌氧消化过程中降解迁移的规律.结果显示,p H为7.5时,总抗生素去除率最高,为55.7%;p H为5.5时,总抗生素去除率最低,仅为21.7%.厌氧消化后,抗生素明显由固相向液相迁移,且总抗生素去除率与其固相迁移至液相的抗生素含量显著相关.

As emerging contaminants,antibiotics could enter the environment through the sludge treatment and disposal processes in the wastewater treatment plant,which brings up the potential threat to human health. In this study,batch experiments were conducted to investigate the degradation and migration of 12 typical antibiotics during the anaerobic sludge digestion at different initial p H values（ p H = 5.5,6.5,7.5,8.5,9.5,10.5）. Results show that the highest removal efficiency of total antibiotics was achieved at the initial p H 7. 5,with a value of 55. 7%,and the lowest value of 21. 7% was observed at p H 5.5. After anaerobic sludge digestion,antibiotics adsorbing in the solid phase dissolved into the liquid phase obviously. Statistical analysis shows that the removal efficiency of total antibiotics was significantly related to the amount of dissolved antibiotics.