TREATMENT OF EMULSIFIED OIL WASTEWATER BY PULSE ELECTRIC FIELD DEMULSIFICATION-ACTIVATED PERSULFATE PROCESS
-
摘要: 乳化油废水普遍具有有机污染物质浓度高、成分复杂,处理难度大的特征。利用脉冲电场,实现油水分离,并结合脉冲电场活化过硫酸盐产生具有强氧化性的SO-4·,对破乳后废水中有机物进行降解。结果表明:脉冲电场破乳试验中,当电源电压为18 V,溶液pH=2,电源频率为800 Hz,占空比为50%,极板间距为2.5 cm,反应时间为50 min时破乳效果最好,对于初始COD浓度为78340 mg/L的乳化油废水,COD的去除率高达98.03%;脉冲电场活化PMS处理破乳后废水试验中,当ρ(PMS),ρ(COD)=3,溶液pH=2,电源电压为15 V,频率为3000 Hz,占空比(一个脉冲循环内,通电时间占总时间的比例)为70%,极板间距为2.5 cm,反应时间为2 h时,乳化油废水中有机物降解率最高达60.8%;且相同条件下,脉冲电源+PMS处理体系较直流电源+PMS处理体系降解率高出6.4百分点。Abstract: Emulsion oily wastewater is difficult to treat because of its high concentration of organic pollutants and complex composition. The pulse electric field was used to realize oil-water separation, and persulfate was activated by the pulse electric field to produce SO-4·with strong oxidation, which degrades the organic matter in the demulsified wastewater. The results showed that in the pulsed electric field demulsification experiment, when the power supply voltage was 18 V, the solution pH was 2, the power supply frequency was 800 Hz, the duty ratio was 50%, the distance between the electrode plates was 2.5 cm, and the reaction time was 50 min, the demulsification effect was the best, and the COD(with an initial value of 78340 mg/L) removal rate was as high as 98.03. In the experiment of treatment of demulsified wastewater by pulsed electric field activated PMS, when ρ(PMS)∶ρ(COD)=3, solution pH=2, power supply voltage was 15 V, frequency was 3000 Hz, duty cycle was 70%, electrode spacing was 2.5 cm, and reaction time is 2 h, the degradation rate of organic matters in emulsified oily wastewater is up to 60.8%; Under the same conditions, the degradation rate of pulse power+PMS treatment system is 6.4% higher than that of DC power+PMS treatment system.
-
Key words:
- emulsion oil wastewater /
- demulsification /
- persulfate /
- electroactivation /
- SO4-·
-
[1] Xl A,LI W A,HLA B,et al.Homogeneous extraction for sustainable separation of emulsified oily wastewater by using CO2 switchable solution[J].Separation and Purification Technology,2021,254:117566. [2] GAO Q,QIAN Y,YANG S Y,et al.Performance and mechanism study on surfactant-stabilized oil microdroplets extraction from oily wastewater[J].Separation and Purification Technology,2023,305:1383-5866. [3] LU H,WU S H,MIAO Z Q,et al.Combination of electric field and medium coalescence for enhanced demulsification of water-in-oil emulsion[J].Chemical Engineering Journal Advances,2021,6:100103. [4] YANG C L.Electrochemical coagulation for oily water demulsification[J].Separation and Purification Technology,2007,54(3):388-395. [5] CHESTERS A K.The modelling of coalescence processes in fluid-liquid dispersions:a review of current understanding[J].Trans IChemE,1991,69:259-270. [6] GAO B C,MHATREA S.Demulsification of crude oil emulsions tracked by pulsed field gradient NMR.Part Ⅱ:influence of chemical demulsifiers in external AC electric field[J].Colloids and Surfaces A:Physicochemical and Engineering Aspects,2020,586:124188. [7] REN B P,KANG Y.Aggregation of oil droplets and demulsification performance of oil-in-water emulsion in bidirectional pulsed electric field[J].Separation and Purification Technology,2019,211:958-965. [8] GOGATE P R,Intensified sulfate radical oxidation using cavitation applied for wastewater treatment[J].Current Opinion in Chemical Engineering,2022,37:100850. [9] LI L,HUANG Y,SU L,et al.Research progress of photocatalytic activated persulfate removal of environmental organic pollutants by metal and nonmetal based photocatalysts[J].Journal of Cleaner Production,2022,372:133420. [10] HUANG X,ZHOU X J,ZHOU J Z,et al.Bromate inhibition by reduced graphene oxide in thermal/PMS process[J].Water Research,2017,122:701-707. [11] LI J Y,WANG H F,REDDY N,et al.MOFFeCo/B-CN composites achieve efficient degradation of antibiotics in a non-homogeneous concurrent photocatalytic-persulfate activation system[J].Science of the Total Environment,2023,858:0048-9697. [12] JOHN P,NANDA G K.Efficient dye degradation via catalytic persulfate activation using iron oxide-manganese oxide core-shell particle doped with transition metal ions[J].Journal of Molecular Liquids,2021,337:116429. [13] YANG L,WU L,LI H,et al.Review on ultrasound assisted persulfate degradation of organic contaminants in wastewater:influences,mechanisms and prospective[J].Chemical Engineering Journal,2019,378:122146. [14] MOEEN G,BEHROOZ A S,ALIREZA P.Electro-activated persulfate oxidation (EC/PS) for the treatment of real oilfield produced water:optimization,developed numericalkinetic model,and comparison with thermal/EC/PS and EC systems[J].Process Safety and Environmental Protection,2021,153:384-402. [15] XU X R,LI X Z.Degradation of azo dye Orange G in aqueous solutions by persulfate with ferrous ion[J].Separation and Purification Technology,2020,72(1):105-111. [16] WANG Y R,CHU W.Degradation of 2,4,5-trichlorophenoxyacetic acid by a novel electro-Fe(Ⅱ)/oxone process using iron sheet as the sacrificial anode[J].Water Research,2011,45(13):3883-3889. [17] 郝会超,方夕辉,唐林旺.电絮凝铁-高级氧化Fenton试剂处理含铅废水的试验研究[J].应用化工,2022,51(7):1924-1928.
点击查看大图
计量
- 文章访问数: 69
- HTML全文浏览量: 12
- PDF下载量: 5
- 被引次数: 0