【摘要】 在冶金冷轧微乳浊液中,醚链较长、αH较多的非离子型表面活性剂的存在导致体系稳定性极高而难于降解,利用热活化过硫酸盐（PS）进行破乳预处理,并联合混凝作用,以实现高效的油水分离.本文研究了PS浓度、体系温度、pH值对上述反应的影响,根据电子顺磁共振等分析技术确定了作用自由基类型及其贡献率,利用气相色谱-质谱联用法分析了反应前后微乳浊液成分,根据激光粒度法测定了反应过程油滴粒径,结果表明:增大PS浓度和温度、降低pH值均有利于提高COD去除率;降解过程包括SO₄^-.、OH.破乳及聚合硫酸铁促使强疏水性油滴脱稳,且SO₄^-.为破乳主导自由基（贡献率86.33%）;基于联合工艺的COD去除率和运行成本均优于热活化PS单一工艺.更多还原

【Abstract】 As for the microemulsion in metallurgical wastewater discharged from cold-rolling process, the existence of non-ionic surfactant with longer ether chain and more αH made the system highly stable and difficult to be degrade. Therefore, thermal-activated persulfate（PS） was used for demulsification pretreatment and the subsequent coagulation was applied to achieve efficient oil-water separation. The influence of PS concentration, temperature and pH value of system was studied first. Electron paramagnetic resonance and other analytical technologies were employed to determine the types and the contribution of free radicals. The initial and the final composition of microemulsion were analyzed by gas chromatography-mass spectrometry, and the diameter of oil droplets was determined via laser particle size analysis. The results showed that the increase of both PS concentration and temperature and the decrease of pH value were conducive to removing COD. The degradation process contained the demulsification via SO₄^-. and OH. and the destabilization of strongly hydrophobic oil droplets by the addition of Polymeric Ferric Sulfate, and SO₄^-. was identified as the dominant species for demulsification（with the contribution of 86.33%）. The comparative evaluation showed that the combined process was better than the barely thermal-activated PS in COD removal and treatment cost.更多还原