单过硫酸氢钾预氧化-铁盐混凝体系降解水中有机物的特性研究

Study on the Degradation Characteristics and Mechanism of Dissolved Organic Matter in Potassium Bisulfate Preoxidation Sulfate Coagulation System

研究单过硫酸氢钾(PMS)预氧化-铁盐(硫酸铁/亚铁)混凝体系在不同PMS浓度、不同混凝剂种类及浓度、不同混凝沉淀时间等条件下最佳的降解效果,并利用湿法氧化(过硫酸盐)-非色散红外探测(NDIR)方法分析水中TOC降解率与不同反应条件的关系。在PMS浓度从200μmol/L增加至800μmol/L时,PMS-Fe^(2+)/Fe^(3+)混凝体系对TOC的去除率分别由9.08%和14.92%增至38.86%和41.78%。Fe^(2+)/Fe^(3+)浓度从200μmol/L增加至800μmol/L时,PMS-Fe^(2+)/Fe^(3+)混凝体系对TOC的去除率分别由6.68%和8.27%增至26.86%和38.22%。反应时间从1 h增加至2.5 h,PMS-Fe^(2+)/Fe^(3+)混凝体系的TOC去除率分别只增加了2.45%和2.72%。结果表明,不同的PMS浓度、不同混凝剂种类及浓度、不同混凝沉淀时间等条件下混凝体系TOC降解率存在差异,PMS浓度及混凝剂浓度对其影响更为明显。在预氧化剂与混凝剂投加量都相同的情况下,混凝沉淀时间对混凝体系TOC去除率的影响不明显,实际工程中可适当减少反应时间。

Study the best degradation effect of potassium bisulfate(PMS)pre-oxidation-ferric salt(ferric sulfate/ferrous sulfate)coagulation system under different PMS concentration,different coagulant type and concentration,different coagulation and precipitation time,and analyze the relationship between TOC degradation rate and different reaction conditions by wet oxidation(persulfate)-nondispersive infrared detection(NDIR)method.When the concentration of PMS increases from^(2)00μmol/L to 800μmol/L,the removal rate of TOC by PMS-Fe^(2+)/Fe^(3+)coagulation system increases from 9.08%and 14.92%to 38.86%and 41.78%respectively.When the concentration of Fe^(2+)/Fe^(3+)increases from^(2)00μmol/L to 800μmol/L,the removal rate of TOC by PMS-Fe^(2+)/Fe^(3+)coagulation system increases from 6.68%and 8.27%to 26.86%and 38.22%respectively.When the reaction time increased from 1h to 2.5 h,the TOC removal rate of PMS-Fe^(2+)/Fe^(3+)coagulation system increased by 2.45%and 2.72%respectively.The results showed that the degradation rate of TOC in the coagulation system was different under the conditions of different PMS concentration,different types and concentrations of coagulants,and different coagulation sedimentation time,and the influence of PMS concentration and coagulant concentration was more obvious.In the case of the same dosage of preoxidant and coagulant,the effect of coagulation sedimentation time on the removal rate of TOC in the coagulation system is not obvious,and the reaction time can be appropriately reduced in practical projects.