Impact of Sulfamethoxazole-A Typical Antibiotic in Water-on Biological Denitrification and Its Mechanism
In order to explore the impact of sulfa antibiotics on biological denitrification in wastewater and discuss their related mechanisms,in this paper,sequencing batch bioreactor(SBR)was used to evaluate the impact of sulfamethoxazole(SMX)on biological denitrification by adding different doses of SMX.The results showed that low SMX concentration(0.1 mg/L)had no significant impact on the characteristics of sludge and the activities of key enzymes.High SMX concentration(＞0.5 mg/L)reduced the biological denitrification efficiency,increased the content of extracellular polymers(EPS)in the sludge,reduced the concentration of sludge,and inhibited the biological nitrification and denitrification.The removal of SMX in the biological denitrification system was affected by the initial SMX concentration,and a higher initial SMX concentration indicated lower removal efficiency of SMX.When SMX concentration was 2.0 mg/L,the removal efficiency of chemical oxygen demand(COD),ammonia nitrogen and total nitrogen(TN)decreased to 76.5％～79.2％,80.6％～84.6％,and 71.6％～73.4％,respectively,and the content of EPS increased to 89.8～91.3 mg/g.The ratio of protein to polysaccharide in the sludge increased to 2.91～2.97,and the sludge concentration decreased to 3.41～3.52 g/L.High concentration of SMX significantly inhibited nitrification and denitrification,which led to decrease in biological denitrification efficiency.The research results enrich the influence behavior of SMX in the whole biological denitrification system in water,and provide some reference for the control of SMX risks.
国家科技期刊平台
NSTL
万方数据
维普
