双介质阻挡放电降解苯酚废水研究

研究了双介质阻挡放电降解苯酚废水过程中不同因素对苯酚降解效果的影响,确定了最佳反应条件,并初步探讨其反应机理。采用自制双介质阻挡放电反应器,以模拟苯酚废水为研究对象,研究了苯酚废水浓度、输入电压、废水曝气量、反应时间等因素对苯酚降解效率的影响。结果表明:输入电压为5 k V,曝气气水比为40∶1,反应时间60 min,降解质量浓度为200 mg/L的模拟苯酚废水,苯酚最大去除率达到95.3%;其中苯酚废水浓度、输入电压、曝气气水比对试验结果影响较大。     

高压脉冲放电等离子体降解苯酚废水

考察了多种因素对高压脉冲放电低温等离子体降解水中苯酚效果的影响。降低放电电极直径、放电距离、废水的电导率和提高废水的pH值以及向废水中通气体和加入硫酸亚铁等均可提高废水中苯酚的降解速率 ,而加入碳酸钠则会降低苯酚的降解速率。初始质量浓度为 10 0mg/L的苯酚废水经放电处理 180min后降解率达 5 0 9%。     

介质阻挡放电等离子体/微曝气协同处理苯酚废水

采用介质阻挡放电等离子体/微曝气技术协同处理苯酚废水,考察放电电压、放电时间、溶液初始浓度及曝气量对苯酚处理效果的影响。研究结果表明:苯酚降解率随放电时间增加、苯酚初始浓度减小而提高;曝气量为150 m L/min时,苯酚降解率为51.8%。采用介质阻挡放电等离子体/微曝气协同工艺处理苯酚废水,与单独使用介质阻挡放电等离子体工艺相比,苯酚降解率提高了15%~20.4%。     

脉冲电晕放电等离子体降解苯酚废水的研究

考察了多种因素对高压脉冲电晕放电等离子体降解废水中苯酚效果的影响，同时对苯酚降解过程动力学进行了研究，提高脉冲电压峰值和气体的流量以及降低废水溶液的电导率均可提高苯酚的降解率，而醇类化合物的存在却明显降低苯酚的降解效果，苯酚的降解过程符合1级反应，降解速率常数（k)与降解温度（T）的关系符合Arrhenius公式，即C＝C0exp(-kt),k=Aexp(-Ea/RT)。当废水的初始pH值和电导率分别为7．0和80uS.cm^-1，脉冲峰压和放电频率分别为32kV和60Hz，放电电极直径和放电距离分别为0．6mm和3．0cm时，指前因子A＝36．0min^-1，表观活化能Ea=24.7kJ.mol^-1。     

高压脉冲电晕放电等离子体降解水中苯酚

对高压脉冲放电等离子体技术降解水中有机污染物苯酚进行了实验研究,观察了脉冲成形电容、脉冲峰值电压、脉冲频率、放电电极直径、放电距离等因素对苯酚降解率的影响;实验结果表明脉冲成形电容有一最佳值;降解率随脉冲峰值电压、脉冲频率增大而升高,随放电电极直径和放电距离的减小而增大。当放电处理320min后,废水的TOC下降62．1％。     

电弧放电等离子体处理苯酚废水的研究

含苯酚废水有毒、 难降解,其排放给周边环境带来了严重的污染.本文采用电弧放电等离子体对苯酚进行了处理.通过实验考察了污染物浓度、电压、反应时间和溶液pH值对对苯酚去除的影响.实验结果表明:浓度为100 mg/L,电压为8 kV,放电处理时间为5 min,pH 2～4之间时,苯酚的降解率达到最大.研究结果为工业废水的处理...     

基于大面积BDD电极的废水降解研究

采用HFCVD方法制作了大面积Ti衬底掺硼金刚石(BDD)电极,并通过SEM、Raman等手段对BDD涂层形貌和质量进行了表征。以模拟苯酚废水作为研究对象,考察大面积BDD电极作为阳极材料的电化学方法对难降解酚类物质的降解速率和效果,主要研究了电流密度、槽压、电极间距、溶液pH值等因素对降解效果的影响,通过检测废水CODCr浓度的变化来探究不同试验条件下BDD电极对苯酚模拟废水的处理效果。结果表明,当电流密度在40~100 mA/cm~2、槽压为8~10 V、电极间距为10 mm、以及弱酸条件下对苯酚废水的处理效果最好。     

针-板式高压脉冲气液两相放电降解废水中的苯酚

为了提高脉冲放电对有机物的降解效果,以苯酚为处理对象建立了单针-板电极形式的脉冲放电体系,考察了各因素对苯酚降解的影响并分析了降解过程中间产物及其浓度变化。结果表明,脉冲电压、电极间距、针-液间距、脉冲频率、曝气量等影响因素对苯酚降解率有很大影响;随着脉冲电压的增大,苯酚降解率增大,电压达到一定值后,苯酚降解率增大不再明显,趋于稳定;随着电极间距、针-液间距、脉冲频率、曝气量的增大,苯酚降解率增大,但当这些因素达到一定值后继续增大,苯酚降解率反而降低。100mL浓度为100mg/L的苯酚废水在电极间距10mm、针-液间距7.5mm、脉冲电压26kV、脉冲频率70Hz、曝气量1.5L/min的最佳条件下,放电60min时苯酚降解率为64.63%,放电140min时达到了85.02%。中间产物间苯二酚、对苯二酚、对苯醌、邻苯二酚在放电过程中浓度随着放电时间的延长先增大后减小,最后浓度都趋于零。其中,间苯二酚浓度最低并且分段出现,对苯醌浓度最大,邻苯二酚最先消失,考察产物变化规律以提高苯酚降解的彻底性。     

三维电极氧化降解苯酚废水的试验研究

采用自制反应器氧化降解苯酚废水,通过试验分析反应时间、pH、电解电压、Fe2+投加量对三维电极氧化降解苯酚废水中苯酚去除效果的影响,并确定最佳反应条件。试验结果表明,三维电极氧化降解苯酚废水有较好的去除效果,在最佳反应条件下,即反应时间为90 min,pH=3,电解电压15 V,Fe2+投加浓度为1 mmol/L,对苯酚质量浓度为300 mg/L的模拟废水的最大苯酚去除率达到91.2%。     

臭氧法降解水中4-氟苯酚动力学研究

采用臭氧法降解4-氟苯酚模拟废水,研究4-氟苯酚降解影响因素和动力学。考察了反应液初始p H、反应物初始浓度、臭氧投量对臭氧氧化4-氟苯酚反应速率的影响。结果表明,4-氟苯酚初始浓度1 mmol/L,p H 10.0,常温常压下反应120 min后,4-氟苯酚总模拟废水的有机碳去除率为56.77%。采用幂指数方程描述反应动力学,4-氟苯酚模拟废水在臭氧氧化下的TOC去除符合表观一级动力学,并得到不同条件下的表观反应速率常数。     

Phenol degradation by isolated bacterial strains: kinetics study and application in coking wastewater treatment

BACKGROUND: In biological treatment of coking wastewater, phenol may decrease the treatment efficiency because of its high concentration and toxicity to microorganisms. Bioaugmentation has been regarded as a good improvement of the traditional biological treatment using isolated degrading strains. In this study, two phenol degrading strains, Pseudomonas sp. PCT01 and PTS02, were isolated and investigated for degradation ability and application to real coking wastewater treatment. RESULTS: Complete phenol degradation was achieved after 18 h inoculation in medium containing 229‐461 mg L^?1 of phenol for both strains. The presence of phenol, pyridine and other compounds in mixed substrate or in coking wastewater prolonged the degradation to 20‐32 h with an initial phenol concentration of 160‐280 mg L^?1. The study of degradation kinetics yielded a two‐stage model to describe the effect of the initial phenol concentration and inhibitory compounds on phenol degradation. The highest degradation rate constant of the second stage, 1.25 h^?1 for PCT01 and 0.75 h^?1 for PTS02, was obtained at low phenol concentration in a single substrate. CONCLUSION: It was found that both strains could degrade phenol effectively and maintain their phenol degradation ability in coking wastewater, and therefore could be used for bioaugmentation treatment of coking wastewater. Copyright © 2011 Society of Chemical Industry     

双极Electro-Fenton法降解水中苯酚的研究

设计了一种双极电化学芬顿方法(Bipolar Electro—Fenton;BEF)并对水中的苯酚进行了降解研究。采用热压法制备了多孔气体扩散碳电极。在无分隔槽反应装置中,以多孔气体扩散碳电极为阴极将氧气还原产生过氧化氢,铁板作阳极产生Fe2 ,直接利用两电极产物发生芬顿(Fenton)反应对苯酚进行降解。TOC、COD的检测结果表明,BEF法中所采用的气体扩散电极对苯酚的降解程度较通常废水处理中以石墨为阴极的电芬(Electro-Fenton;EF)更为彻底;而且BEF法对苯酚的降解速率比传统芬顿法更快。     

苯酚降解菌的筛选与降解特性研究

以沈阳北部废水处理厂活性污泥为菌源,经过驯化、培养、筛选出一种降解能力较强的菌株GP6,该菌为球菌,革兰氏染色阴性,能以苯酚为唯一碳源和能源生长,降解苯酚的最佳条件为：温度30℃,pH7．0,振荡转速150r／min,好氧。进而研究了氮源和碳源等因素对苯酚生物降解的影响。     

Fenton试剂-改性粉煤灰处理苯酚废水的研究

以模拟苯酚废水为研究对象,初步研究了Fenton试剂-改性粉煤灰体系处理有毒有机废水时各影响因子的作用机制。通过混凝搅拌实验,确定了室温时先快速搅拌1 min（转速为350 r/min）、然后慢速搅拌10 min（转速为50 r/min）、再静置沉淀30 min条件下,Fenton试剂处理模拟苯酚废水（质量浓度为100 mg/L）的最佳条件：pH为4,加入质量分数为5%的硫酸亚铁溶液2 mL,加入质量分数为3%的过氧化氢溶液5 mL。在此条件下苯酚的去除率达到85.2%。实验还发现,再增加投加改性粉煤灰,投加量为100 mg/L时,苯酚的去除率可达到99.3%。并通过自由基的氧化和混凝吸附两种机理对这种促进作用进行了解释。Fenton试剂-改性粉煤灰体系处理苯酚废水具有处理效率高、反应速率高、成本低廉、操作方便等优点,具有较好的实际应用前景。     

活性炭纤维吸附石化废水中苯酚的吸附平衡及动力学

以活性炭纤维(ACF)为吸附剂,研究了ACF对石化废水中苯酚的吸附平衡及动力学。在25、40、55及65℃下测定了吸附平衡等温线,采用Langmuir、Freundlich和Redlich-Peterson等温方程对吸附平衡数据进行了拟合,结果表明吸附平衡数据更符合Langmuir与Redlich-Peterson方程。体系温度从25、40、55升高到65℃时,ACF对模拟废水中苯酚的吸附能力随温度升高而降低,而ACF对石化废水中苯酚的吸附能力并不完全随温度升高而降低。ACF对石化废水与模拟废水中苯酚的吸附过程均符合拟二级动力学方程。颗粒内扩散模型对吸附动力学实验数据的拟合结果表明,吸附初期吸附速率主要受颗粒内扩散控制且石化废水中苯酚吸附的k_id随温度升高而增大,吸附中后期吸附速率除了受颗粒内扩散控制外还受到外扩散的影响。热力学分析表明,石化废水中ACF吸附苯酚过程的ΔG<0,由于石油类物质对苯酚吸附的影响,温度升高ΔG的数值变化不大。     

煤制天然气废水处理技术研究现状及展望

为实现煤制天然气项目的"废水零排放",论述了煤制天然气"废水零排放"主要工艺,如酚氨回收、有机废水处理、含盐废水处理、浓盐水处理、高浓盐水处理、结晶盐处理等,并分析了各工序处理技术的特点及存在问题,并对煤制天然气及煤化工废水零排放处理发展趋势进行展望。未来应通过生产系统与水系统的优化,研究废水处理与利用的新途径,实现废水减量化;提高酚氨回收过程的回收效率及装置稳定性,降低运行成本;开发抗毒生化技术;研发高性能、抗污染膜材料,形成新工艺;开发经济、可靠的浓盐水脱除COD技术;开发高回收率、高纯度的分盐结晶工艺;形成煤化工废水结晶盐产品标准,促进废水结晶盐资源化利用。     

Developmental studies of an adaptive on-line softsensor for biological wastewater treatments

Efficient monitoring and automatic control systems for biological wastewater treatment processes, especially those dealing with bioinhibitory pollutants, such as phenol, are urgently required in order to meet increasingly stringent environmental regulations. Practical on-line sensors of variables that describe water quality, such as BOD or individual toxic pollutants such as phenol, are not commercially available; e.g. phenol is generally monitored off-line by spectrofluorometry. Inference software sensors could be an attractive alternative for on-line monitoring of these variables. As a first step towards the development of inferential sensors for biological wastewater treatment processes, we consider in this study, a simplistic version of such a process which consists of a continuous culture of Pseudomonas putida Q5 degrading phenol. In this work, we propose a neural network based inferential sensor for phenol monitoring using on-line biomass concentration measurements by spectrophotometry. The network was built with wavelets as the basis functions and the adaptive algorithm for the weights was based on a Lyapunov stability analysis. Predicted phenol output of the network showed good agreement with experimental data, over fairly broad ranges of inlet phenol concentration and dilution rate step changes. Simulations were conducted to find convergence conditions and to investigate possible sources for errors in phenol estimates.     

Easy removing of phenol from wastewater using vegetable oil-based organic solvent in emulsion liquid membrane process

Phenol is considered as pollutant due to its toxicity and carcinogenic effect.Thus,variety of innovative methods for separation and recovery of phenolic compounds is developed in order to remove the unwanted phenol from wastewater and obtain valuable phenolic compound.One of potential method is extraction using green based liquid organic solvent.Therefore,the feasibility of using palm oil was investigated.In this research,palm oil based organic phase was used as diluents to treat a simulated wastewater containing 300×10~(-6) of phenol solution using emulsion liquid membrane process(ELM).The stability of water-in-oil(W/O) emulsion on diluent composition and the parameters affecting the phenol removal efficiency and stability of the emulsion;such as emulsification speed,emulsification time,agitation speed,surfactant concentration,pH of external phase,contact time,stripping agent concentration and treat ratio were carried out.The results of ELM study showed that at ratio7 to 3 of palm oil to kerosene,5 min and 1300 r·min~(-1) of emulsification process the stabile primary emulsion were formed.Also,no carrier is needed to facilitate the phenol extraction.In experimental conditions of500 r·min~(-1) of agitation speed,3%Span 80,pH 8 of external phase,5 min of contact time,0.1 mol·L~(-1) NaOH as stripping agent and 1:10 of treat ratio,the ELM process was very promising for removing the phenol from the wastewater.The extraction performance at about 83%of phenol was removed for simulated wastewater and an enrichment of phenol in recovery phase as phenolate compound was around 11 times.     

湿式氧化工艺处理高浓度苯酚废水试验研究

以高浓度苯酚废水为研究对象,采用湿式氧化（WAO）工艺对其进行CODCr降解试验。考察了反应温度、反应压力、废水pH值、苯酚初始质量浓度及反应时间等对WAO处理效果的影响。在此基础上,采用正交试验方法获得了相应的工艺参数,在废水初始pH值为12,初始CODCr的质量浓度为20 000 mg/L,反应温度为240℃,反应压力为4 MPa,反应时间不少于80 min的条件下,CODCr去除率可达89%。研究结果可为含酚废水WAO处理工艺的工程设计提供依据。