Study On Coking Plant Wastewater With Coagulation/Iron-Carbon Internal Electrolysis

Coking wastewater is a kind of high-color and refractory organic wastewater, produced in the processes of the pyrolysis (heating in absence of air) of suitable grades of coal, purifying coal gas and refining chemical products. At present, pretreatment and activated sludge process following are commonly used in coking wastewater. However, COD and chroma of bio-chemical effluent generally cannot meet emission standard. For the main problems of coking wastewater, coagulation-iron-carbon inner electrolysis was studied systemically in this paper, providing a potential technical solution to reduce COD and chroma such as pollution index of coking wastewater.First of all, coagulation, iron-carbon inner electrolysis, iron-carbon inner electrolysis- coagulation and coagulation-iron-carbon inner electrolysis were researched preliminarily into dealing with coking wastewater respectively. The results showed that: the removal rate of COD and chroma of PFS coagulation were the lowest in the four methods. Coagulation-iron-carbon inner electrolysis had a significant effect and COD and chromas of effluent reduced to 115 mg/L and 30, the removal rate of which could reach 74.8% and 98.1% respectively.Finally, the mechanism of coagulation and iron-carbon inner electrolysis to remove organic matter was discussed preliminarily in coking wastewater by UV-2550 scanned spectrograms.