Efficient Activation Of Peroxymonosulfate By Metal Oxide For Drilling Wastewater Removal

The advanced oxidation technology of sulfate radical is a oxidation technology which the persulfate?PS or PMS?generates strong oxidative sulfate radical?SO4-·?by the catalytic activation of transition metals,light or heating,and using SO4-· to degrade organics into small molecules,CO2 and H2 O.In recent years,the technology has become a research focus in the field of environmental management such as remediation of soil and groundwater,landfill leachate and treatment of refractory organic.In the paper,the research object were taken from a oil field drilling wastewater in Sichuan,according to the results of water quality safety analysis to reduce the harm of pollutants to the ecological environment.The study on the treatment of drilling wastewater by metallic oxide activated persulfate was carried out in combination with the advanced oxidation technology of sulfate radical and photocatalytic technology.The contents are as follows:?1?Study on the treatment of drilling wastewater by CuFe₂O₄/PMS System.The spinel CuFe₂O₄ catalysts were prepared by coprecipitation method,and were characterized by X-ray diffraction?XRD?,Fourier transform infrared spectroscopy?FT-IR?,scanning electron microscopy?SEM?and comprehensive physical properties?PPMS?.The effects of initial pH value,amount of catalyst and oxidant,reaction time and reaction temperature were investigated on the removal of CODCr.Results showed the Cu Fe2O4 had the best effect on the activation of potassium peroxysulfate,and the removal rate of CODCr in drilling wastewater was 72.19% and the ratio of BOD5/CODCr increased from 0.0283 to 0.1588 which improved the biodegradability as the mass of CuFe₂O₄ was 0.1 g and the PMS was 0.9 g,the value of pH was 7 at 30 ? for 3 h.?2?Study on the treatment of drilling wastewater by advanced oxidation technology of sulfate radical and photocatalytic technology.1)The effects of advanced oxidation technology of sulfuric acid radical and visible light photocatalytic technology on the drilling wastewater were studied by using RuO2-Cu0.95Mn0.03La0.02Fe2O4 as catalyst.The catalysts were synthesized by coprecipitation-impregnation method,and were characterized by X-ray diffraction?XRD?,scanning electron microscopy?SEM?,X-ray energy dispersive spectroscopy?EDS?and comprehensive physical properties?PPMS?.The results of single-factor experiments showed that the CODCr removal rate of drilling wastewater had reached 84.76%,BOD5/CODCr was 0.3196 as the amount of catalyst was 0.1 g and the PMS was 1.2 g,pH was 5,the xenon lamp was 300 W at 30 ? for 3 h.The wastewater had reached the biodegradable conditions.2)The ability of free radical oxidation and the photocatalytic treatment of drilling wastewater were studied.The catalysts were prepared by impregnation method,and were characterized by X-ray diffraction?XRD?,scanning electron microscopy?SEM?and X-ray energy dispersive spectroscopy?EDS?.The results showed that the CODCr removal rate was 82.73% and the BOD5/CODCr value increased from 0.0283 to 0.2646 as the amount of catalyst was 0.1 g and 1.8 g of PMS,250 W of UV power,the initial pH of 5 at 35 ? for 2.5 h,and the performance of biodegradable was also improved.The synergetic treatment of sulfate radical advanced oxidation technology and photocatalytic technology is effective for drilling wastewater,after treatment CODCr of the wastewater decreased,and the biodegradability was improved.it can reduce the harm to the environment and human and accord with the management concept of health,safety and environment?HSE?integration.