UV-TiO2联用去除饮用水中阴离子表面活性剂的研究

采用UV-TiO2催化氧化联用工艺去除饮用水中低含量阴离子表面活性剂LAS.试验考察了玻璃纤维网膜数目、涂敷次数和LAS的初始浓度对LAS去除效果的影响,在LAS浓度为1 mg/L,紫外光强度为4 mw/cm2,3张玻璃纤维网膜分别涂敷3次条件下,反应100 min后,LAS的去除率超过90%.并建立了UV-TiO2催化氧化联用工艺降解LAS的动力学方程.     

高级氧化+SBR工艺处理聚乙二醇废水试验研究

研究了高级氧化+SBR组合工艺处理高浓度聚乙二醇(PEG)废水的效果及其影响因素。结果表明,采用芬顿试剂作为高级氧化剂,当FeSO4.7H2O投加量为800 mg/L,H2O2投加量为30 mL/L,反应时间为3.5 h时,CODCr去除率可达到50.5%;生化处理阶段所需采用两级SBR工艺,污泥浓度均为4 000 mg/L,一、二级厌氧及好氧反应时间分别为12和10 h;芬顿试剂氧化和厌氧处理对提高PEG废水的可生化性有明显效果;该组合工艺的出水水质可以达到《污水综合排放标准》(GB 8978—1996)中的二级排放标准。     

微电解/Fenton法深度处理土霉素废水的研究

采用微电解/Fenton法对土霉素废水二级出水进行深度处理。正交和单因素试验结果表明,微电解法的最佳工艺条件:Fe投量为125 g/L、铁炭质量比为1.5∶1、初始pH值为4.0、反应时间为2 h,在进水COD为361～395 mg/L的条件下,处理后出水COD可降至198～207 mg/L,对COD的去除率可达44%以上;采用Fenton法进一步处理微电解出水,其最佳工艺条件:H2O2(浓度为30%)投加量为2 mL/L、初始pH值为3.0、反应时间为60 min,处理后出水COD<120 mg/L,组合工艺对COD的总去除率达到70%以上,满足《发酵类制药工业水污染物排放标准》(GB21903—2008)的要求。     

Electro‐oxidation of phenol in petroleum wastewater using a novel pilot‐scale electrochemical cell with graphite and stainless‐steel electrodes

This work investigated the removal of phenol from petroleum wastewater by the electro‐oxidation process. The experimental design was developed on a pilot‐scale electro‐oxidation system equipped with a cylindrical shape of graphite electrodes as an anode and stainless‐steel electrodes as a cathode. An initial study was performed based on operating variables such as current density and time on real petroleum wastewater. The optimum conditions were obtained as a current density of 3 mA/cm² and time 15 min. Under these applied optimum conditions, complete phenol removal from an initial concentration of about 6.8 mg/L was achieved. Also, 50–60% removal of organic matter in terms of chemical oxygen demand (COD) and biological oxygen demand (BOD). The removal of organic matter using electro‐oxidation requires a long reaction time. Also, the economic study indicated that the energy consumption was determined to be 0.79 kWh/m³ and the operating cost was 0.051 $/m³ which is very economical compared with conventional methods.     

Fenton试剂氧化法深度处理焦化废水的研究

以实际焦化废水经A2O工艺处理后的出水为研究对象,考察了Fenton试剂氧化法深度处理焦化废水的效果和影响因素。结果表明,Fenton试剂氧化法对焦化废水具有良好的深度处理效果,在进水COD为100～340mg/L、色度为480～940倍的条件下,出水COD和色度等指标均可达到《城市污水再生利用工业用水水质》(GB/T19923—2005)的要求。在试验条件下,最佳的反应参数:初始pH值为2.5,反应温度为40～50℃,Fe2+投加量为0.4mmol/L,反应时间为2～3h,H2O2投加量为4～8mmol/L。     

Fenton氧化处理炼化废水中苯酚的实验研究

通过单因素实验探索了Fenton氧化炼化废水中苯酚的最佳工艺条件。实验结果表明,Fenton试剂处理苯酚废水时,最佳氧化反应条件为:pH=3.5,反应温度为20℃,H2O2投加量为12mL·L-1,反应时间为30min,FeSO4·7H2O投加量为600mg·L-1。因此用Fenton氧化法处理含苯酚废水是一种非常有效的方法。     

Chemical treatment of an anionic surfactant wastewater: Electrospray-MS studies of intermediates and effect on aerobic biodegradability

The effect of wet air oxidation on the aerobic biodegradability of a model wastewater containing 1000 mg L(-1) of linear alkylbenzene sulfonate (LAS) has been investigated. Semibatch oxidation experiments were performed temperature of 473 K, oxygen partial pressure of 1.3 MPa and residence times varying from 40 to 390 min, while continuous oxidation experiments were performed at a residence time of 120 min. Oxygen uptake tests were performed to assess the aerobic biodegradability of both the oxidised and the original LAS solutions using cultures that had been adapted to both LAS and oxidation intermediates. The concentration of total organic carbon, chemical oxygen demand and active detergent were followed throughout the wet oxidation and biodegradation experiments, while the main intermediates formed during wet oxidation were identified by means of Electrospray-MS and high performance liquid chromatography. It was found that LAS could be easily oxidised at 473 K to yield a group of molecules with short alkyl chains which do not behave as active detergents. Sulfonated aromatics are produced as intermediates which have had the alkyl chains shortened. The segments of alkyl chains broken off the intermediate compounds appear primarily as short chain organic acids. The original unoxidised 1000 mg L(-1) LAS solution was found to be readily biodegradable in the laboratory aerobic reactors operating at low organic loadings and substrate to microorganism concentration ratios. However, wet oxidation resulted in effluents that were less readily biodegradable than the original LAS with biodegradability decreasing with increasing degree of oxidation. These results suggest that, at the conditions under consideration, a combined chemical pre-oxidations and biological post-treatment process may be less effective in removing LAS than a single-stage biological or chemical process.     

Ultrasound-assisted photo-Fenton process for treatment of pulp and paper mill wastewater and reduction of phytotoxicity

The efficiency of classical Fenton (CF) and modified Fenton (MF) as well as photo-Fenton processes in real wastewater treatment of pulp and paper (P&P) mill was investigated in this study. The chemical oxygen demand (COD) was chosen as the reference measurement for evaluating the treatment's efficiency. After determining the optimum parameters for each process, the effect of adding ultrasound (US) on improving treatment efficiency was examined. In addition, kinetic study and phytotoxicity analysis were conducted under optimum conditions for all processes. With pH 4, reaction time 50 min, 1.2 g/L Fe²⁺ and 8 g/L H₂O₂ dosages, the best removal efficiency (RE) of COD was determined to be 82.18% in CF process, and this rate rose to 90.1% when US was added. The best RE in MF process was 84.16% with the application of UV-C, pH 4, reaction time 50 min, 1 g/L Fe⁰ and 8 g/L H₂O₂ doses, although it increased to 93.4% when US was applied. The greatest results in the seed germination test were achieved in US processes with 100% of germination percentage (GP) for spinach and tomato and 90% for cress. In the economic evaluation, when conducting the treatment without US, the estimated relative cost decreased in a 15 and 16%, for CF/UV-C and CF processes respectively, whereas the CF process was 64% cheaper than the MF process in all applications. The US contributed to enhanced water treatment efficiency by having a significant synergistic impact on Fenton applications. Hence, the combination of photo-Fenton and ultrasound to treat effluent from P&P mills proved to be an effective and promising technique.     

蒽醌染整废水的混凝沉淀-Fenton催化氧化处理

采用混凝沉淀-Fenton催化氧化组合工艺对蒽醌染整废水进行处理，研究了混凝剂和Fenton试剂投加量以及各种反应条件对处理效果的影响。试验结果表明，当pH值为6．2、A12（SO4）3投量为300mg／L、PAM投量为3mg／L、沉淀时间为30min时，混凝沉淀出水的COD为233～260mg／L，色度为15～20倍；后续处理采用Fenton试剂催化氧化，当FeSO4投量为200mg／L、H2O2投量为100mg／L、pH值为5．0、反应时间为30min时，出水色度≤10倍，BOD5≤10mg／L，COD≤50mg／L。     

Fenton试剂强化铁炭微电解预处理高浓有机废水

研究了Fenton试剂法强化铁炭微电解工艺对高浓度难生化有机废水的预处理效果。结果表明，当原水COD在9000mg／L、铁炭微电解反应时间为100min、pH值为2．2时，铁炭微电解对原水COD的去除率〉45％；铁炭微电解出水再投加240mg／L的H2O2（30％）进行Fenton试剂法处理，常温下反应50min对原水COD的去除率可提高到75％以上。铁炭微电解＋Fenton试剂联合工艺的除污效果好、运行稳定、成本低廉，适宜对高浓度难生化有机废水的预处理。     

铁炭微电解/Fenton预处理对叔丁酚甲醛树脂合成废水

采用铁炭微电解/Fenton试剂法联合工艺预处理对叔丁酚甲醛树脂合成废水,考察了pH、反应时间及H_2O_2投量等因素的影响.结果表明,当原水COD为12 300～17 600 mg/L时,在控制原水pH值为2.0、反应时间为120 min的条件下,铁炭微电解对COD的去除率>50%;向铁炭微电解出水中再投加2.4 mL/L的H_2O_2(30%)进行Fenton反应,在常温(20～30℃)下反应60min对COD的总去除率>83%,废水的B/C值从最初的0.034提高到0.35左右.对预处理出水(调节pH并稀释)进行后续的生化处理,出水水质能够稳定达到<污水综合排放标准>(GB 8978-1996)的二级排放标准要求.     

Destruction of cresols by Fenton oxidation process

The present study was used to probe the treatment of simulated wastewater containing cresols by Fenton process. Experiments were conducted in a batch reactor to examine the effects of operating variables like pH, hydrogen peroxide concentration (H(2)O(2)) and ferrous ion concentration (Fe(2+)) on chemical oxygen demand (COD) removal. The progress of the degradation reaction was monitored by the decrease in COD content in the treated solution. The optimal reacting conditions were experimentally determined and it was found to be [H(2)O(2)]=31.64 mM, [Fe(2+)]=0.90 mM for o- and p-cresol while 0.72 mM for m-cresol at pH=3.0+/-0.2. The degradation efficiency for cresol isomers was as high as 82% within 120 min at optimum conditions. A pseudo-first-order kinetic model was adopted to represent the Fenton oxidation for cresols. The mineralization rate for cresols obeys the following sequence: m->p->o-. Maximum degradation occurred at 30 degrees C for the temperature range of 20-50 degrees C studied. The global activation energy for the first-order reaction was estimated to be in the range of 12.90-16.25 kJ/mol. Air/nitrogen did not play an active role in completely mineralizing the organic intermediates at the experimental conditions adopted. Irrespective of the position of methyl group in o-, m- or p-position, the maximum dissolved organic carbon (DOC) removal efficiency was 42%. Only 2/5th of cresol was mineralized to CO(2) by Fenton process. The results showed that the cresols were completely oxidized and degraded into lower molecular weight aliphatic acids. Among the acids, acetic and oxalic acids were identified as the major products formed during the degradation.     

Electrochemical treatment of chemical oxygen demand in produced water using flow‐by porous graphite electrode

Produced water is the largest wastewater stream generated in the oil and gas industries. In this study, experiments were carried out using a bench‐scale electrochemical cell using flow‐by porous graphite electrode, for oxidation of organic matter in produced water which was collected from natural gas processing field (real sample). The effect of anodic current density and influent feed flow rate on chemical oxygen demand (COD) removal efficiency, and energy consumption were investigated. The maximum removal efficiency of 66.52% was obtained for a flow rate of 50 mL/min, current density of 1.41 mA/cm² and pH of 7.3 for an influent COD of 2845 mg O₂/L. The energy consumption at these conditions was 2.12 kWh/kg_COD.     

UV/Fenton法处理LCD清洗废水的后续工艺研究

简要评价了UV／Fenton法处理液晶显示屏清洗废水的效果，并对其出水的后续处理工艺做了进一步的研究。结果表明：UV／Fenton法能有效降解液晶显示屏清洗废水中的有机物，在合适的反应条件下，能使废水的COD由1468mg／L降至99mg／L，但出水的浊度和色度仍较高。将UV／Fenton法处理出水的pH值调至7左右，配合投加PAC和PAM，反应后静沉20—30min，出水浊度、色度和残余铁离子浓度均大大降低，达到了理想的出水效果。PAC、PAM的适宜投量分别约为10mg／L和0．4mg／L。     

响应面法优化电解芬顿协同法深度处理老龄垃圾渗滤液

采用电解芬顿法深度处理老龄垃圾渗滤液,选取电量、进水 pH 值、进水氨氮浓度3个因素为变量,CODCr 去除率为响应值进行 Box-Behnken 中心组合设计。利用响应面法对试验结果进行分析,建立了 CODCr 去除率为响应值的二阶多项式模型并进行了方差分析和显著性检验,通过解模型逆矩阵得到最佳条件：单位面积电量为23．26 Ah／dm2、pH 值为3．58、进水氨氮浓度56．78 mg／L。在最佳条件下,CODCr 去除率为96．5％,与模型预测值偏差为4．45％,吻合度较高。对电解芬顿深度处理前后的渗滤液进行 GC-MS 分析,表明电解芬顿协同处理技术能有效降解垃圾渗滤液中难生化降解的有机物,将有机物种类从42种降低至21种,是较有效的深度处理技术。     

Treatment of olefin plant spent caustic by combination of neutralization and Fenton reaction

Spent caustic from olefin plants contains much H2S and some mercaptans, phenols and oil. A new treatment process of spent caustic by neutralization followed by oxidation with Fenton's reagent (Fe2+/H2O2) was successfully developed. Over 90% of dissolved H2S were converted to gas phase by neutralization at pH = 5 and T = 70 degrees, and the vent gas stream could be introduced to sulfur recovery plant. The neutralized liquid was oxidized with OH. free radical, which was provided by a Fenton's reagent. The residual sulfides in the neutralized spent caustic were oxidized to less than 0.1 mg/L. The total COD removal of spent caustic is over 99.5% and the final COD value of the effluent can be lower than 100 mg/L under the following oxidation conditions: reaction time = 50 min, T = 90 degrees, Fe2+ = 100 mg/L, and a stoichiometric H2O2/COD = 1.1. The value is better than the 800 mg/L value obtained by common WAO process. The optimum pH of the Fenton reaction is around 2 for this process, and the oxidation step can maintain a pH value in the range of 1.8-2.4. Moreover, the iron catalyst can be recycled without affecting process effectiveness thus preventing secondary pollution.     

微波-生物接触氧化法处理制药废水的研究

为探讨微波与生物接触氧化法用于处理制药废水的可行性,进行了相关试验研究.考察了微波处理对制药废水中COD的去除效果,结果表明：在微波辐射时间为2、8、10 min的条件下,对COD的去除率随着微波功率的增加呈相同的变化趋势;微波功率为382.5、434、459、510 W的条件下,对COD的去除率均随微波辐射时间的延长而有不同程度的提高;降低pH值有利于提高微波处理对COD的去除率.应用微波与生物接触氧化的组合工艺处理制药废水的试验结果表明：生物接触氧化的最佳处理时间为760 min;微波处理对COD的去除率为10%～15%,生物接触氧化法直接处理时,对原水COD的去除率较低,出水COD＞300mg/L;经过微波处理后（459 W、8min）再进行生物接触氧化处理（760 min）,则对COD的总去除率＞95%,最终出水的COD＜300mg/L,表明该组合工艺用于处理制药废水是可行的.     

混凝预处理洗浴废水中的LAS

以洗浴废水为研究对象,比较了铝盐、铁盐及有机高分子混凝剂对洗浴废水中的LAS去除效果,筛选出聚合氯化铝（PAC）作为混凝剂处理效果较好,进而采用单因素试验研究了混凝剂的投加量,废水的pH,静沉时间,搅拌强度和搅拌时间对LAS去除率的影响,结果表明PAC投加量为45 mg/L,废水pH值为6.0～8.0,静沉时间为15 min,中速（150 r/min）搅拌3 min,慢速（50 r/min）搅拌10 min时混凝效果最佳,对LAS的去除率达44.75%。     

Fe-H2O2深度处理造纸中段废水的研究

为解决零价铁法处理废水时效率偏低的问题,采用Fe-H2O2法对造纸中段废水的二级处理出水进行了深度处理,分别考察了pH值、反应时间、铁炭比、曝气量和H2O2投量对色度和COD去除率的影响.结果表明：在pH值为3.5、铁炭比（体积比）为1.2、曝气量为1.4 L/min、铁屑粒径为60～80目、H2O2投量为40～60 mg/L的最优条件下,当处理时间控制在35 min时,对色度和COD的去除率可分别达到98%和77%左右,出水可回用.     

铁炭Fenton/SBR法处理硝基苯制药废水

为探寻硝基苯废水的适宜处理工艺，开展了铁炭Fentort／SBR工艺处理硝基苯制药废水的试验研究。结果表明，铁炭内电解结合Fenton氧化的预处理工艺可有效去除废水中的硝基苯类物质，并提高了废水的可生化性。当原水的pH值为2～3、H2O2投加量为500～600mg／L时，调节预处理出水pH值至7～8并经沉淀处理后，对COD和硝基苯类物质的总去除率分别可达47％和92％。后续混合废水经SBR工艺处理后出水水质能满足国家污水排放标准。