College of Environmental Science & Engineering, Beijing Forestry University, Beijing 100083, China.
J Environ Sci (China). 2011;23(5):725-30. doi: 10.1016/s1001-0742(10)60465-2.
Ultrasonic/O3 combined process was employed to pretreat heterocyclic pesticide wastewater for increasing biodegradability and reducing biological toxicity. Influences of ultrasonic frequency, ultrasonic power, probe diameter, initial pH and O3 dosage on the COD removal were studied. The results showed that the ultrasonic/O3 process significantly improved the biodegradability and reduced the biological toxicity of the wastewater. The ratio of BOD5/COD was increased from 0.03 to 0.55 and the EC50 increased from 11% to 52% under ultrasonic/O3 treatment. Low ultrasonic frequency brought better COD removal. Initial pH was found to have a high influence on the COD removal and alkaline conditions were more favorable. The influences of ultrasonic power and probe diameter were small. With an increase in O3 dosage, COD removal was effectively improved. The optimal operational parameters for the combined process on COD removal were ultrasonic frequency 20 kHz, initial pH 9.00, ultrasonic power 300 W and dosage of O3 454.8 mg/(L min), under which the efficiency of COD removal reached 67.2%.
超声/O3 联合工艺用于预处理杂环类农药废水以提高可生物降解性和降低生物毒性。研究了超声频率、超声功率、探头直径、初始 pH 值和 O3 用量对 COD 去除率的影响。结果表明，超声/O3 工艺显著提高了废水的可生物降解性和降低了生物毒性。超声/O3 处理后，BOD5/COD 比值从 0.03 增加到 0.55，EC50 从 11%增加到 52%。低超声频率带来更好的 COD 去除率。初始 pH 值对 COD 去除率有很大影响，碱性条件更为有利。超声功率和探头直径的影响较小。随着 O3 用量的增加，COD 去除率得到有效提高。在 COD 去除率的最佳联合工艺操作参数为：超声频率 20 kHz、初始 pH 值 9.00、超声功率 300 W 和 O3 用量 454.8 mg/（L·min），在此条件下，COD 去除率达到 67.2%。
