Abstract:

Sodium hypochlorite, ozone and Fenton reagent chemical oxidation process have been used for the pretreatment of coking wastewater. The COD_Cr, NH₄⁺-N removing efficiencies and the improvement of wastewater biodegradability by using three kinds of reagents are investigated. The results show that sodium hypochlorite oxidation treatment has higher NH₄⁺-N removing rate, but the improvement of wastewater biodegradability is not high. Under O₃ oxidation treatment, the removing rates of COD_Cr and NH₄⁺-N are comparatively low, but the wastewater biodegradability increases rapidly. After reacted for 3 min, wastewater biodegradability is increased from 0.068 to 0.281. By Fenton reagent oxidation treatment, under optimal conditions, the wastewater biodegradability reaches 0.445, but the running costs are high. It is considered comprehensively that ozone oxidation applied to the pretreatment of coking wastewater is more appropriate.

Key words: coking wastewater, pretreatment, biodegradability, O₃, Fenton reagent

摘要：

采用次氯酸钠、臭氧及芬顿试剂化学氧化法对焦化废水进行预处理，考察了3种药剂对焦化废水COD_Cr、氨氮的去除效果及废水可生化性的提高。结果表明，次氯酸钠氧化处理对焦化废水中氨氮的去除率较高，但对废水可生化性的提高不大；臭氧氧化处理对焦化废水中COD_Cr和氨氮的去除率均较低，但对废水的可生化性提高迅速，反应3 min后废水的可生化性即可由0.068提升到0.281；采用芬顿试剂氧化处理，在较佳条件下，废水的可生化性可达到0.445，但运行成本高。综合考虑，采用臭氧氧化预处理焦化废水更具优势。

关键词: 焦化废水, 预处理, 可生化性, 臭氧, 芬顿试剂

CLC Number: 

• X703.1