摘要：

采用电催化氧化—活性炭处理焦化废水生化出水，研究电流密度、极板数量、间距、活性炭种类等因素对处理效果的影响。在生化出水COD为136.6 mg/L、TOC为56.6 mg/L条件下，当极板数量为2对、间距为1.8 cm、电流密度为20 mA/cm²、反应6 h时，电催化出水COD去除率可达99.7%，TOC去除率为47.87%。相较于椰壳炭，比表面积大的煤质炭对电催化处理出水的吸附效果较好。当煤质炭投加量为20 g/L、反应120 min时，活性炭出水TOC总去除率可达67.88%。煤质炭吸附废水中有机物的过程更符合准二级动力学模型，颗粒内扩散模型反映该吸附是一个复杂过程。三维荧光光谱表征表明，电催化能氧化分解生化出水中部分类腐殖酸物质，活性炭可进一步吸附去除残留的类腐殖酸物质。

关键词: 电催化氧化, 活性炭, 焦化废水, 生化出水

Abstract:

Electrocatalytic oxidation-activated carbon adsorption was applied to treat biochemical effluent of coking wastewater. The effects of current density, the number of polar plates, electrode interval and the kind of activated carbon on the treatment efficiency were investigated. Under the condition of biochemical effluent COD 136.6 mg/L, TOC 56.6 mg/L, polar plates of 2 pairs, electrode interval of 1.8 cm, current density of 20 mA/cm² and reaction time 6 hours, the COD and TOC removal rate of electrocatalytic effluent reached 99.7% and 47.87%, respectively. The coal-based charcoal with larger specific surface area had better adsorption performance than coconut shell charcoal. When the dosage of coal-based charcoal and reaction time was 20 g/L and 120 minutes, the total TOC removal rate reached 67.88%. The adsorption process of organic matter in wastewater by coal-based carbon was well described by the pseudo-second-order model, and the intragranular diffusion model showed that the adsorption process was a complicated process. The results of three-dimensional fluorescence spectra showed that electrocatalytic oxidation could decompose some humic acid-like compounds in wastewater, and activated carbon adsorption might further remove residual humic acid-like compounds.

Key words: electrocatalytic oxidation, activated carbon, coking wastewater, biochemical effluent

中图分类号: 

• X703