缺氧-好氧生物滤池中高效菌对活性红KN-3B的降解特性

Biodegradation behavior of reactive red KN-3B by highly effective decolorizing strain in anaerobic-aerobic biofilter

为了研究高效脱色菌在缺氧-好氧生物滤池(A/O biofilter)中对偶氮染料的降解特性,以活性红KN-3B(C.I.reactive red 180)为降解对象,缺氧生物滤池以火山碎石为填料,接种高效脱色菌CK3柯氏柠檬酸杆菌启动,好氧生物滤池以牡蛎壳为填料,接种污水处理厂活性污泥启动。试验考察了不同工况下缺氧-好氧生物滤池对色度和COD的去除效果,结果表明:生物滤池中微生物对偶氮染料活性红KN-3B的脱色和对COD降解的最适pH条件为弱酸性;缺氧滤池中高效菌对色度的去除需要外加碳源,且增加外加碳源有助于脱色率的提高;该高效菌为耐盐菌,当进水NaCl浓度达30 g/L时,色度去除率仍可达93%以上;当染料负荷达500 mg/L时,脱色率仍可达95%。通过紫外-可见扫描图谱分析初步推断CK-3柯氏柠檬酸杆菌对偶氮染料活性红KN-3B的脱色主要是生物降解作用。

The decolorization and degradation of azo dye reactive red KN-3B（C.I.reactive red 180） in an anoxic-aerobic biofilter（A/O biofilter） was studied in this research.The anoxic biofilter packing with volcano detritus was incubated with high effective decoloring strain Citrobacter sp.CK3.The aerobic biofilter packing with shells was incubated with activated sludge taken from a domestic wastewater treatment plant.The optimum operation conditions for color removal was determined,results show that the optimum pH for the degradation of azo dye reactive red KN-3B and organic matter is weakly acidic; nevertheless, the degradation performance is still good under alkaline condition; the strain can not decolorize reactive red KN-3B without external carbon source; furthermore, decolorization efficiency is improved when the carbon source concentration is increasing; the strain is salt-tolerate, decolorization efficiency is still more than 93% , when initial NaCl concentration reaches to 30 g/L; decolorization efficiency can still be 95% , when the initial dye concentration reaches to 500 mg/L. The result based on UV-Vis analyses to dye wastewater before and after decolorizing reaction suggests that reactive red KN-3 B may be removed mainly due to the biodegradation.