氧化/吸附/混凝协同工艺处理焦化废水生物处理出水的过程及效果分析

针对焦化废水生物处理出水中继续存在多种有机污染物而影响达标及存在安全隐患的现状,基于废水中有机物的物理化学特性,构建了氧化/吸附/混凝的深度处理过程。在NaC lO投加量为40 mg/L,AC投加量为500 mg/L,PFS投加量为300 mg/L,反应时间为0.5 h,以及pH为7.0的最佳条件下,先氧化后吸附混凝,该过程可以实现COD去除率为75%以上,色度去除率80%以上,处理后的水样其COD值与色度值分别下降到60 mg/L及20倍以下;通过GC/MS方法分析处理前后水样中的有机物组分,发现水样中大部分单环芳香族化合物和多环芳香族化合物,部分含氮杂环化学物、有机氯化物以及溴化物被去除,但是,长链烷烃和部分芳香烃继续保留。研究结果证明了氧化/吸附/混凝协同工艺的效果与焦化废水生物出水中有机污染物的分子结构、存在形态形成构效关系,催化作用与氧化作用的协同是获得高效去除率的关键。

Process and effectiveness analysis of treatment of biologically treated coking wastewater by oxidation/adsorption/coagulation

Considering the existence of the variety organic pollutants and the safty risks in biological treated coking wastewater,the advanced process of oxidation/adsorption/coagulation was builded,based on the physical and chemical characteristics of organic matter.Under the reaction conditions of PFS concentration 300 mg/L, NaClO concentration 40 mg/L,AC concentration 500 mg/L,reaction time 0.5 h and pH 7.0, the COD and chroma moval rates were above 75% and 80%, separately, besides the COD and chroma droped to 60 mg/L and 20 below separately after the treatment of oxidation first and then absorption and coagulation to the coking wastewater. In addition, GC/MS was used to carry out the qualitative analysis of organic compositions in wastewater, the majority of wastewater monocyclic aromatic compounds and polycyclic aromatic compounds, some heterocyclic chemicals, organic chlorides and bromides were removed, but part of long chain alkanes and aromatic hydrocarbons was almost non functional.The results showed that the effect of the process of oxidation/adsorption/coagulation had the structure activity relationship with the structures and the forms of the organic compounds, the synergy of oxidiation and catalytic was the key to efficient removal.