可见光/Fe^(2+)/过硫酸盐法处理油田废水

Treatment of Oilfield Wastewater by Visible Light/Fe^(2+)/Persulfate Systems

对比了可见光/Fe^(2+)/过硫酸盐法和Fe^(2+)/过硫酸盐法对辽河油田采油废水处理效果,并分析了可见光/Fe^(2+)/过硫酸盐法好于普通Fe^(2+)/过硫酸盐法的原因。COD为410 mg×L^(-1)采油废水经可见光/Fe^(2+)/过硫酸盐法处理后,COD降至70mg×L^(-1);而用Fe^(2+)/过硫酸盐法处理,COD降至101 mg×L^(-1)。红外光谱(FTIR)、X射线衍射分析证明两体系中生成聚铁的形态不完全一样,Ferron络合比色法的测试结果进一步表明,可见光/Fe^(2+)/过硫酸盐体系中生成聚铁的絮凝性能好于普通Fe^(2+)/过硫酸盐体系。紫外可见光谱分析的结果证明,废水中的烷烃类在两体系中转化方式相同,芳香类在两体系中转化方式不同。可见光法好于普通法的原因是:可见光体系中生成了絮凝性能更好的聚铁,并且芳香类中间产物在可见光下具有光敏性,导致废水中的有机物在两体系中的转化方式不同。

This study compared the effects between visible light/Fe^（2＋）/persulfate and Fe^（2＋）/persulfate systems on the treatment of oil extraction wastewater from Liaohe Oilfield, and the reason of the visible light/Fe^（2＋）/persulfate system showed better performance than the Fe^（2＋）/persulfate system was investigated. The results show that wastewater COD drops from 410 mg×L^（-1） to 70 mg×L^（-1） by the visible light/Fe^（2＋）/persulfate system, whereas it decreases to 101 mg×L^（-1） when using the Fe^（2＋）/persulfate system. Infrared spectroscopy（FTIR） and X-ray diffraction results indicate that the poly ferric compounds formed in the two systems are not exactly the same. Ferron complex colorimetric study further confirms that the poly ferric compounds from the visible light/Fe^（2＋）/persulfate system have superior flocculation performance than that of the Fe^（2＋）/persulfate system. Moreover, UV-Vis results demonstrate that the degradation of alkanes in the two systems has the same pathway, while the aromatics degradation is different. Better performance with the addition of visible lights may attribute to higher flocculation of poly-ferric compounds as well as the photosensitiveness of aromatic intermediate products in the visible light/Fe^（2＋）/persulfate system, which cause different reaction processes of organics in wastewater.