太阳光Fenton氧化-混凝联合处理含酚废水

研究了煤气含酚废水和模拟苯酚废水的太阳光Fenton氧化-混凝联合处理技术,比较了混凝法、太阳光Fenton氧化法及其联合技术对含酚废水的处理效果。结果表明,太阳光Fenton体系可有效地氧化降解含酚废水,但废水完全矿化所需的H2O2用量较大,导致处理成本较高。含酚废水直接采用混凝处理的效果不理想,CODCr和挥发酚去除率较低(6.5%～28.7%)。采用太阳光Fenton氧化-混凝联合技术处理中等浓度的煤气含酚废水,使其CODCr和挥发酚浓度达到国家二级排放标准,只需投加700mg/L的H2O2,而单纯采用太阳光Fenton氧化所需消耗的H2O2大于2800mg/L,即联合技术可节约H2O2用量3倍以上。结果还表明晴天下太阳光Fenton氧化反应45min与人工电紫外光Fenton氧化反应30min对含酚废水的处理效果相当。太阳光Fenton氧化-混凝联合技术具有能耗低、处理效率高、处理量大等特点,在环境治理领域具有更广阔的应用前景。

SOLAR PHOTO-FENTON OXIDATION-COAGULATION COMBINED PROCESSES FOR THE TREATMENT OF PHENOLIC WASTEWATER

The treatment of phenolic wastewater by solar photo-Fenton-coagulation combined processes have been studied. The treatment efficiency of phenolic wastewater by single solar photo-Fenton oxidation, single coagulation and combined processes have been compared. Effective degradation of phenolic wastewater have been observed by solar photo-Fenton process, but complete mineralization of phenolic wastewater need to consume large numbers of H2O2, so the single solar photo-Fenton oxidation is uneconomical technology. Experimental results showed that the solar photo-Fenton oxidation-coagulation combined processes for treatment of phenolic wastewater are very efficient and more economical, comparing with the single solar photo-Fenton oxidation and single coagulation process, the high removal efficiency of COD and phenol can be obtained by combined processes. The COD and phenol in coal-gas wastewater are reduced to national control standard by combined processes as using 700mg/L H2O2 in solar photo-Fenton oxidation process, the same treatment efficiency can be obtained by single solar photo-Fenton oxidation process as H2O2 larger than 2800mg/L. So three times of H2O2 were saved by combined processes comparing with single solar photo-Fenton process. The data also indicates the same catalysis in photo-Fenton oxidation can be obtained by irradiating 45 minutes with the natural solar light or by irradiating 30 minutes with the electric UV-light. The solar photo-Fenton-coagulation combined processes are more effective and economical methods, so can be expected to be applied extensively in wastewater treatment.