O3-SBBR联合工艺深度处理印染工业园生化尾水的效能和机制

针对印染工业园生化尾水中生物难降解的有机氮难题，采用O₃-SBBR(臭氧-序批式生物膜反应器)联合工艺进行深度处理.开展了影响因素实验、降解动力学和淬灭实验，测定了自由基种类、琥珀酸脱氢酶活性和脱氮功能基因.结果表明，适宜的臭氧氧化条件：pH为8.0～8.5、ρ(O₃)为35.0 mg·L^-1左右、 O₃投加量(以O₃/H₂O计，下同)约为100.0 mg·L^-1和反应时间为90.0～120.0 min.臭氧氧化生化尾水的有机氮符合拟一级动力学模型，最大速率常数k值为0.010 35 min^-1实验条件：pH为8.0、 O₃投加量为150.0 mg·L^-1和ρ(O₃)为35.0 mg·L^-1].臭氧氧化显著提高序批式生物膜反应器(SBBR)的脱氮性能，脱氮效率从19.8%(SBBR)提高到32.9%(O₃

Efficiency and Mechanism of O3-SBBR Combined Process for Advanced Treatment of Biochemical Effluent from Printing and Dyeing Industrial Park

With the aim of addressing the difficult problem of biodegradable organic nitrogen in biochemical effluent of a printing and dyeing industrial park, the combined ozonation-sequencing batch biofilm reactor (O₃-SBBR) process was used for advanced treatment. The influencing factors and degradation kinetics were analyzed; quenching experiments were carried out; and the types of free radicals, succinate dehydrogenase activity, and denitrification function genes were determined. The results showed that the suitable ozonation condition was pH 8.0-8.5, O₃ concentration was approximately 35.0 mg·L^-1, O₃ dosage was approximately 100.0 mg·L^-1, and reaction time was 90.0-120.0 min. Organic nitrogen in the biochemical effluent by ozonation conformed to the pseudo first-order kinetic model, and the maximum rate constant k was 0.01035 min^-1 (experimental conditions:pH 8.0, ozone dosage 150.0 mg·L^-1, and ozone concentration 35.0 mg·L^-1). Ozonation significantly improved the denitrification performance of the sequencing biofilm batch reactor (SBBR), and the denitrification efficiency increased from 19.8% (SBBR) to 32.9% (O₃-SBBR). Ozonation could convert organic nitrogen and organic substances with strong toxicity and difficult biological utilization into small molecular substances with low toxicity and biodegradability. The abundance of functional genes (nirS, nirK, and nor) in the O₃-SBBR combined process was significantly higher than that in the single SBBR, which further confirmed that ozonation could improve the nitrogen removal performance of SBBR. The operation cost of the combined process was 0.74-1.07 yuan·m^-3, with good technical economy. This study provided a basis for the application of the O₃-SBBR combined process in the advanced treatment of biochemical effluent in printing and dyeing industrial parks.