Advanced oxidation treatment of physico-chemically pre-treated olive mill industry effluent

In this study, the applicability of physico-chemical methods was investigated for the pre-treatment of the olive mill effluents prior to the discharge into the common sewerage ending with a municipal wastewater treatment plant. The samples were taken from an olive oil industry operated as three-phase process located in Turkey. Various pre-treatment methods including acid craking, polyelectrolyte and lime additions were applied. Advanced oxidation study using Fenton's process was also investigated following pre-treatment by acid cracking and cationic polyelectrolyte. Acid cracking alone gave satisfactory treatment efficiencies and polyelectrolite additions to the acid-cracked samples enhanced treatment efficiency. Since a complete treatment plant is available at the end of the sewer system, results indicated that the effluents of the investigated industry could be discharged into the municipal sewerage in the case of total chemical oxygen demand (COD(tot)), suspended solid (SS) and volatile suspended solid (VSS) concentrations according to the Turkish Water Pollution Control Regulation after pre-treatment with 5 ppm anionic polyelectrolyte following acid cracking. The minimum COD(tot), SS and VSS removals were observed when raw wastewater was pre-treated with lime and the discharge standards to the municipal sewer system could not be met. Advanced oxidation with Fenton's process was applied after acid cracking and cationic polyelectrolyte treatment in order to investigate further reduction in chemical oxygen demand (COD) concentration for minimizing the influence of this industrial discharge on the existing municipal wastewater treatment plant. Results indicated that COD(tot) removal increased up to 89% from 74% after Fenton's oxidation for the acid cracked samples in which cationic polyelectrolite (10 ppm) was added.     

Pre-oxidation and coagulation of textile wastewater by the Fenton process

This paper evaluates the Fenton process, involving oxidation and coagulation, for the removal of color and chemical oxygen demand (COD) from synthetic textile wastewater containing polyvinyl alcohol and a reactive dyestuff, R94H. The experimental variables studied include dosages of iron salts and hydrogen peroxide, oxidation time, mixing speed and organic content. The results show that color was removed mainly by Fenton oxidation. The color removal reached a maximum of 90% at a reaction time of 5 min under low dosages of H2O2 and Fe2+. In contrast, the COD was removed primarily by Fenton coagulation, rather than by Fenton oxidation. The ratio of removal efficiency between Fenton process and ferric coagulation was 5.6 for color removal and 1.2 for COD removal. It is concluded that Fenton process for the treatment of textile wastewater favors the removal of color rather than COD.     

Fenton-水解酸化-接触氧化处理模拟磷霉素钠制药废水

对模拟磷霉素钠制药废水进行Fenton-水解酸化-接触氧化小试处理实验,考察了COD、有机磷的去除效果,并对处理前后的废水进行了GC-MS分析。结果显示,增加了Fenton预处理后磷霉素钠制药废水的COD和有机磷分别降低到100和2 mg/L,去除率均可达87%以上,出水COD满足化学制药行业污染物排放标准(GB 21904-2008);Fenton过程对制药厂废水中的复杂有机物去除效果明显,GC-MS结果表明,出水中基本检测不到复杂有机物。与制药厂采用的水解酸化-接触氧化处理效果相比,增加Fenton预处理可以提高废水的可生化性和系统的处理效率。     

含表面活性剂的采油废水催化氧化处理

对含有表面活性剂的废水(以下简称表活废水)进行了傅里叶红外光谱分析(FTIR),结果表明,废水中所含表面活性剂主要为环烷酸钠。采用次氯酸钙(Ca(ClO)2)和活性炭-Ni催化氧化处理,在Ca(ClO)2投加量为4 500 mg/L,活性炭-Ni投加量为7 000 mg/L时,反应90 min,出水COD为158.91 mg/L,去除率达62.92%。催化氧化出水经沸石吸附处理,在pH为6.85,吸附时间为2 h,沸石投加量为17 g/L的条件下,吸附出水COD和油含量分别为88.92 mg/L和2.53mg/L,去除率分别为45.65%和90.02%,均达到《污水综合排放标准(GB8978-1996)》的一级标准要求。催化剂活性炭-Ni和吸附剂沸石均具有较稳定的活性,在重复使用20次后,出水COD的去除率仅分别降低了1.16%和1.32%。     

Combination of ozonation with conventional aerobic oxidation for distillery wastewater treatment

Laboratory-scale experiments were conducted in order to investigate the effect of ozone as pre-aerobic treatment and post-aerobic treatment for the treatment of the distillery wastewater. The degradation of the pollutants present in distillery spent wash was carried out by ozonation, aerobic biological degradation processes alone and by using the combinations of these two processes to investigate the synergism between the two modes of wastewater treatment and with the aim of reducing the overall treatment costs. Pollutant removal efficiency was followed by means of global parameters directly related to the concentration of organic compounds in those effluents: chemical oxygen demand (COD) and the color removal efficiency in terms of absorbance of the sample at 254 nm. Ozone was found to be effective in bringing down the COD (up to 27%) during the pretreatment step itself. In the combined process, pretreatment of the effluent led to enhanced rates of subsequent biological oxidation step, almost 2.5 times increase in the initial oxidation rate has been observed. Post-aerobic treatment with ozone led to further removal of COD along with the complete discoloration of the effluent. The integrated process (ozone-aerobic oxidation-ozone) achieved approximately 79% COD reduction along with discoloration of the effluent sample as compared to 34.9% COD reduction for non-ozonated sample, over a similar treatment period.     

电絮凝处理牛仔布印染废水

用铁分别作为电絮凝反应系统的阴极和阳极,研究电絮凝法对牛仔布印染废水的处理效果。考察了电极电压、反应时间和pH等因素对电絮凝法去除实验所用废水中COD和色度效果的影响。结果表明,电极电压和反应时间是主要的影响因素,pH次之。电极电压24 V,反应时间35 min,pH为7.4时,脱色率可达99%,COD去除率在70%左右,处理效果最佳。因此,电絮凝法可以作为印染废水的预处理工艺,有效降低废水COD和色度。     

Fe (III) supported on resin as effective catalyst for the heterogeneous oxidation of phenol in aqueous solution

FeIII supported on resin as an effective catalyst for oxidation was prepared and applied for the degradation of aqueous phenol. Phenol was selected as a model pollutant and the catalytic oxidation was carried out in a batch reactor using hydrogen peroxide as the oxidant. The influent factors on oxidation, such as catalyst dosage, H2O2 concentration, pH, and phenol concentration were examined by considering both phenol conversion and chemical oxygen demand (COD) removal. The FeIII-resin catalyst possesses a high oxidation activity for phenol degradation in aqueous solution. The experimental results of this study show that almost 100% phenol conversion and over 80% COD removal can be achieved with the FeIII-resin catalyst catalytic oxidation system. A series of prepared resin were investigated for improving the oxidation efficiency. It was found that the reaction temperature and initial pH in solution significantly affected both of phenol conversion and COD removal efficiency. The activity of the catalyst significantly decreased at high pH, which was similar to the Fenton-like reaction mechanism. Results in this study indicate that the FeIII-resin catalytic oxidation process is an efficient method for the treatment of phenolic wastewater.     

臭氧/活性炭联合工艺深度处理焦化废水

采用臭氧/活性炭联合工艺对焦化废水A2/O出水进行深度处理。考察了溶液初始pH值、臭氧投加量、活性炭投加量及使用次数、反应时间对焦化废水处理效果的影响。实验结果表明,活性炭的使用可显著提高臭氧对焦化废水COD的去除率,在溶液初始pH值为10.25、臭氧投加量为7.5 mg/min、活性炭投加量50 g/L、反应时间为30 min条件下,COD去除率达到73.51%。同时,在活性炭重复使用10次时,COD去除率为70.85%,仅降低了2.66%。     

微生物制剂与玄武岩纤维联斥处理城市废水

为了探索一种新型的去除水体中有机物的工艺,以模拟城市废水为研究对象,研究不同工况条件下,复合微生物制剂、组合双环玄武岩纤维填料以及复合微生物制剂与组合双环玄武岩纤维填料结合对模拟城市废水中COD的去除情况。实验结果表明,复合微生物制剂与组合双环玄武岩纤维填料结合在曝气的情况下对COD的去除能力较高。在复合微生物制剂与组合双环玄武岩纤维填料结合的条件下,对COD浓度为500mg／L左右的模拟城市废水的去除效率可达97．22％;影响模拟城市废水中COD去除效果的各因素的主次顺序依次为反应时间〉曝气时间〉投加量=pH;得出最佳工况参数是：复合微生物制剂的投加量为0．05g／L,曝气时间为72h,反应时间为96h,pH为7。     

微生物制剂与玄武岩纤维联用处理城市废水

为了探索一种新型的去除水体中有机物的工艺,以模拟城市废水为研究对象,研究不同工况条件下,复合微生物制剂、组合双环玄武岩纤维填料以及复合微生物制剂与组合双环玄武岩纤维填料结合对模拟城市废水中COD的去除情况。实验结果表明,复合微生物制剂与组合双环玄武岩纤维填料结合在曝气的情况下对COD的去除能力较高。在复合微生物制剂与组合双环玄武岩纤维填料结合的条件下,对COD浓度为500 mg/L左右的模拟城市废水的去除效率可达 97.22%;影响模拟城市废水中COD去除效果的各因素的主次顺序依次为反应时间>曝气时间>投加量=pH;得出最佳工况参数是:复合微生物制剂的投加量为0.05 g/L,曝气时间为72 h,反应时间为96 h,pH为7。     

光催化氧化处理有机废水

介绍了光催化氧化法的原理,对光催化氧化法处理有机废水的可行性进行了试验,探讨了ＣＯＤ随反应时间的变化规律及催化剂用量,温度、浓度的影响。试验表明,光催化氧化可降解象洗涤剂这样难降解的有机物,反应１２０ｍｉｎＣＯＤ去除率可达５０％以上。     

Advanced oxidation treatment of physico-chemically pre-treated olive mill industry effluent

In this study, the applicability of physico-chemical methods was investigated for the pre-treatment of the olive mill effluents prior to the discharge into the common sewerage ending with a municipal wastewater treatment plant. The samples were taken from an olive oil industry operated as three-phase process located in Turkey. Various pre-treatment methods including acid craking, polyelectrolyte and lime additions were applied. Advanced oxidation study using Fenton's process was also investigated following pre-treatment by acid cracking and cationic polyelectrolyte. Acid cracking alone gave satisfactory treatment efficiencies and polyelectrolite additions to the acid-cracked samples enhanced treatment efficiency. Since a complete treatment plant is available at the end of the sewer system, results indicated that the effluents of the investigated industry could be discharged into the municipal sewerage in the case of total chemical oxygen demand (COD_tot), suspended solid (SS) and volatile suspended solid (VSS) concentrations according to the Turkish Water Pollution Control Regulation after pre-treatment with 5 ppm anionic polyelectrolyte following acid cracking. The minimum COD_tot, SS and VSS removals were observed when raw wastewater was pre-treated with lime and the discharge standards to the municipal sewer system could not be met. Advanced oxidation with Fenton's process was applied after acid cracking and cationic polyelectrolyte treatment in order to investigate further reduction in chemical oxygen demand (COD) concentration for minimizing the influence of this industrial discharge on the existing municipal wastewater treatment plant. Results indicated that COD_tot removal increased up to 89% from 74% after Fenton's oxidation for the acid cracked samples in which cationic polyelectrolite (10 ppm) was added.     

O3／UV预处理磺酰脲类除草剂生产废水的研究

采用O3／UV工艺预处理磺酰脲类除草剂生产废水,考察了初始pH值、臭氧投量、叔丁醇投加等因素对废水处理效果的影响,并初步探讨了该工艺处理废水的反应机理。实验结果表明,在废水初始pH为13．59和臭氧投量为65．08mg／min的条件下,预处理80min后废水COD去除率达63．47％,BOD5／COD由0．03提高至0．56,EC50从11％提高至55％。随着叔丁醇浓度的增加,废水COD去除率明显降低,证明该反应体系有·OH存在;体系中加入MnO2后废水COD去除率下降了16％,氧化效率明显下降,证明该反应体系内中间产物HO2O在O3／UV降解有机废水过程中起到了重要的作用。     

臭氧预氧化处理葡萄酒废水

葡萄酒废水的季节性波动常造成生化处理系统不稳定,使传统的生化处理工艺难以满足新的污水排放标准的要求。研究了臭氧预处理工艺对葡萄酒废水的处理效果及主要控制参数,结果表明,单独的臭氧预氧化对COD几乎无去除效果,但对色度的去除可达到90%;采用O3/H2O2组合工艺可使COD的去除率提高4倍。经臭氧预处理的出水再采用SBR进行好氧处理时,出水COD能降至80 mg/L以下,COD的降解速度及程度都高于未经臭氧处理的稀释原水。高效液相色谱(HPLC)分析显示,经臭氧处理后,除麦芽糖成分被完全去除外,其他各种成分的数量变化不大;GC/MS对废水中多酚类有机物的分析显示,臭氧预处理可将大量难降解的多酚类有机物分解,从而有助于后续生化处理的出水达到更高的污水排放标准。     

微波辅助工艺处理天然气净化废水的应用研究

进行了微波辅助工艺处理天然气净化废水的应用研究,考察了废水色度、COD、SS、含油量和细菌的去除效果以及对废水腐蚀率的降低作用,并进行了同等条件下的常温对照实验。研究结果表明:微波絮凝工艺中絮凝剂PAC和PAM的用量较常温下减少了100 mg/L和5 mg/L,絮凝沉降时间仅为常温絮凝的1/4,最佳微波辐照时间下废水的COD去除率比常温条件下提高4.6%。微波工艺处理后,难降解天然气净化废水的含油量去除率达到了94%、废水中硫酸盐还原菌死亡率达97%以上,废水腐蚀率降为原来的1/7,废水可生化性得到了很大提高,可直接进行好氧生化处理。实验表明,微波辅助工艺对难降解天然气净化废水具有很好的处理应用效果。     

微曝气Fenton氧化法处理模拟双酚A废水的效果及其生物验证

研究了微曝气Fenton氧化法关键工艺参数对模拟双酚A（BPA）废水处理效果的影响,并从活性污泥性质和污染物去除率两方面,采用膜生物反应器(membrane bioreactor, MBR)对微曝气Fenton氧化法的处理效果进行了实验验证,为实现BPA废水的生物处理奠定基础。结果表明,初始pH值、反应时间、H₂O₂/COD(质量浓度比)、H₂O₂/Fe²⁺ (摩尔浓度比)、反应温度及曝气量均对预处理效果有较大影响,在最佳条件下,COD去除率可达70%,BOD/COD值则由原废水的0.02提高到0.50以上。MBR处理上述出水的结果表明,经微曝气Fenton氧化处理BPA的废水,可较好地适应后续的生化处理。     

高浓度钻井废水的混凝-催化氧化处理

以华北油田某深井的高浓度钻井废水(COD高达14 460.0 mg/L)为研究对象,提出了酸化-混凝-催化氧化-吸附的组合处理工艺。重点研制了钻井废水催化氧化处理催化剂(镍基催化剂),通过实验确定了最佳工艺参数条件。着重考察了催化氧化处理的工艺条件,在pH值为4,次氯酸钙投加量为4.4 g/L,催化剂投加量为1.6 g/L的条件下COD降至403.5 mg/L,进一步吸附处理后COD降至139.9 mg/L、色度为30倍、石油类含量为3.8 mg/L、pH为8.0和SS浓度为52mg/L,最终出水水质达到《污水综合排放标准》(GB 8978-1996)二级标准,处理成本为84.8元/m3。     

混凝辅助电化学法处理橙黄G染料废水

以石墨板为阳极,研究了电化学氧化法对橙黄G染料废水的降解效果。比较了在NaCl、Na2 SO4以及NaCl与FeSO4·7H2O组合的支持电解质体系中的处理效果,同时考察了电压、初始pH、电解质浓度、电极间距和电解时间等因素对废水中橙黄G脱色率及COD去除率的影响。研究结果表明,橙黄G的脱色主要是活性氯的氧化作用,橙黄G分子的矿化可能主要是电解过程中产生的·OH的作用,FeSO4·7H2O的加入增加了混凝作用,使得处理效果进一步提高。最佳脱色条件下橙黄G脱色率和COD的去除率分别为97．6％和56．3％,B／C（BOD／COD）由0．09提高至0．41,可生化性有较大改善,并且随着降解时间的增加,COD去除率逐渐升高。此结果表明,橙黄G废水COD的去除相对于脱色存在滞后性。     

碱催化H2O2氧化法预处理奶牛养殖废水的试验研究

采用碱催化H2O2氧化法对奶牛养殖废水进行预处理试验,研究了温度、pH、H2O2投加量、反应时间等参数对COD去除效果的影响,确定了反应最佳运行条件。试验结果表明,碱催化H2O2氧化法在pH7~12时,对COD的去除率为40%~60%;当反应温度50℃,pH值9,H2O2投加量2.72 g/L,反应时间20 min时,COD的去除率为66.3%。     

铁碳微电解预处理汽车电泳涂装废水

采用铁碳微电解法对汽车电泳涂装废水进行处理,研究其处理效果及COD降解动力学。结果表明,进水pH≤4时,铁碳微电解的处理效果影响因素依次为铁碳反应次数、反应时间、进水pH。COD降解率随微电解反应时间的增加而升高,随反应次数的增加而降低,之后趋向稳定。当进水pH=3,反应时间90~150 min时,铁碳微电解的处理效果可稳定在40%左右。同时通过模拟分析,汽车电泳涂装废水COD降解动力学符合三级反应动力学模型。