磁性TiO2/GO复合催化剂处理垃圾渗滤液试验研究

制备了二氧化钛/氧化石墨烯（TiO₂/GO）和磁性二氧化钛/氧化石墨烯（磁性TiO₂/GO）两种复合催化剂,并用其处理垃圾渗滤液。考察了复合催化剂中TiO₂与GO的质量比、催化剂投加量、反应时间对COD去除率的影响,并采用SEM、XRD、VSM、FTIR等手段对复合催化剂进行表征。结果表明,磁性TiO₂/GO复合催化剂表面粗糙、纯度高、磁回收性能良好。当TiO₂与GO的质量比为5∶1、催化剂投加质量与垃圾渗滤液COD的质量比为0.8、反应时间为3 h时,对COD的去除率最高,可达65.35%,此时垃圾渗滤液出水COD为1 774 mg/L,可生化性（BOD₅/COD）由0.20提高至0.45。     

Cu_2O/氧化石墨烯催化氧化垃圾渗滤液的因素分析

采用Cu_2O、氧化石墨烯、Cu_2O/氧化石墨烯复合催化剂处理垃圾渗滤液,分析催化剂种类、投加量、反应时间对处理效果的影响。试验结果表明,Cu_2O/氧化石墨烯复合催化剂处理垃圾渗滤液的效果最好,最佳试验条件为复合催化剂质量∶渗滤液COD质量=0.7,反应时间为1h。在最佳试验条件下,处理后的垃圾渗滤液的NH_4~+-N浓度达到2 454 mg/L,对COD的去除率可达93.33%,BOD_5/COD值为0.84。     

接触氧化/厌氧氨氧化/微波工艺处理垃圾渗滤液

采用生物处理/厌氧氨氧化/物化处理组合工艺处理垃圾渗滤液,系统能稳定运行且对污染物的去除效果较好.组合工艺对垃圾渗滤液中COD的平均去除率为94.97％,出水COD平均为47.5 mg/L;对NH3 -N的平均去除率为98.53％,出水NH3 -N平均为14.62 mg/L;对TN的平均去除率为98.23％,出水TN平均为21.3 mg/L;对TP的平均去除率为69.82％,出水TP平均为2.22 mg/L.渗滤液出水COD、NH3-N、TN、TP浓度均满足《生活垃圾填埋场污染控制标准》(GB16889-2008)的一级标准.     

两级接触氧化联合Fenton试剂处理垃圾渗滤液

利用Fenton试剂深度处理两级生物接触氧化工艺出水,以解决生化处理出水水质不达标的问题.结果表明,两级生物接触氧化工艺可有效去除垃圾渗滤液中的氨氮,对氨氮的总去除率高达99.0%,对总氮的去除率也达到了41.1%,但出水COD值高达415 ms/L,且大部分为难生物降解有机物,需进行深度处理.利用Fenton试剂深度处理生化工艺出水,在H2O2和Fe2+投量均为3 mmol/L、pH值为6的最佳反应条件下,Fenton反应对COD的去除率高达53.2%,出水COD值降到195 mg/L,达到国家二级排放标准.     

两级A/O-Fenton-BAF工艺处理垃圾渗滤液

针对垃圾渗滤液的水质特征,采用厌氧折流板反应器/一级好氧/接触厌氧/二级好氧/Fenton氧化/曝气生物滤池工艺处理垃圾渗滤液.原水COD约为1 300 mg/L,氨氮约为300mg/L,运行结果表明,该工艺运行稳定,系统对COD的去除率达到93%,对氨氮的去除率达到98%,出水COD<100 mg/L、氨氮<25 mg/L、色度<40倍、悬浮物<30 mg/L,达到<生活垃圾填埋场污染控制标准>(GB 16889-2008)中表2的排放标准.     

臭氧高级氧化组合技术处理垃圾渗滤液达标

分别选取上海某垃圾焚烧厂及填埋场的垃圾渗滤液MBR出水为处理对象,采用臭氧高级氧化(AOP)技术,并结合混凝预处理及生化处理进行小试.结果表明:对于垃圾焚烧厂MBR出水,采用AOP1(O3)/生化/AOP2(O3组合)处理,当总AOP投加量在3～3.5个单位时就可达到COD＜ 100 mg/L的新排放标准;对于垃圾填埋场MBR出水,采用混凝/AOP(O3/H2O2)处理,当AOP投加量为6个单位时就可达到COD＜100 mg/L的排放标准.综合经济性因素,臭氧氧化组合处理工艺[(混凝)/AOP1(O3)/生化/AOP2(O3/H2O2)]为垃圾渗滤液深度处理的最佳方式.     

BBR+Fenton氧化+BAF组合工艺处理垃圾渗滤液

介绍了武汉陈家冲生活垃圾卫生填埋场采用BBR——基于芽孢杆菌(Bacillus)为优势菌群的生物处理系统+Fenton氧化+BAF组合工艺处理垃圾渗滤液原液的工程实例。实际运行数据表明,该工艺对垃圾渗滤液中的有机物、NH~+_4-N及TN具有良好且稳定的去除效果。当BBR系统进水COD≤14 000 mg/L、NH~+_4-N≤2 500 mg/L、TN≤3 000 mg/L时,BBR系统出水COD≤1 300 mg/L、NH~+_4-N≤28 mg/L、TN≤275mg/L;深度处理段出水COD≤96 mg/L、NH~+_4-N≤7.6 mg/L、TN40 mg/L,出水各项指标均达到了《生活垃圾填埋场污染控制标准》(GB 16889—2008)。组合工艺处理成本为103.20元/t,具有良好的经济效益和环境效益。     

混凝/化学氧化/曝气生物滤池深度处理垃圾渗滤液

随着垃圾渗滤液的老龄化,常规的生化处理已经不能使出水达标排放,需要进行深度处理。采用混凝／化学氧化／曝气生物滤池联合工艺深度处理垃圾渗滤液,进水COD为700mg／L左右,出水COD〈100mg／L,去除率〉85％,排放口水质达到《生活垃圾填埋污染控制标准》（GB16889--1997）一级标准。     

微波强化Fenton氧化法处理垃圾渗滤液试验研究

针对垃圾渗滤液中难降解有机物的处理效能低、成本高的问题,探讨了微波强化Fenton氧化法处理垃圾渗滤液的效能,考察了微波加热时间、微波功率、催化荆投量、pH、Fenton试剂投量等对处理效能的影响,并通过正交试验考察了各因素的综合影响.试验结果表明:在pH值为2.5、H2O2投量为6.25 mL/L、FeSO4·7H2O投量为3.972 g/L、反应时间为5 min、活性炭投量为5 g/L的条件下,可使渗滤液COD由1 652 mg/L降至205 ms/L(去除率为87.5%),达到垃圾渗滤液的二级排放标准.各因素对处理效果的影响程度依次为:Fenton试剂投量>pH>催化剂投量>反应时间.与Fenton氧化法相比,微波强化Fenton氧化法可节省50%的投药量,降低了处理成本.     

高效硝化耦合臭氧催化氧化深度处理石化废水中试

采用高效硝化(HENT)耦合臭氧催化氧化技术深度处理某石化公司丙烯腈废水。中试结果表明,HENT处理效果良好,在进水氨氮为88~286 mg/L的条件下,出水氨氮平均为0.53mg/L,去除率为99.72%。COD主要通过臭氧催化氧化和BAF来去除,在进水COD平均浓度为259 mg/L的条件下,出水平均浓度可降至57 mg/L,对COD的平均去除率达到了75.6%;随着BAF运行的稳定,当进水COD200 mg/L时,出水COD可降至40 mg/L以下。另外,高效硝化耦合臭氧催化氧化技术对总氰化物、SS、硫化物和总磷也有一定的去除效果。     

微波催化氧化处理垃圾渗滤液工况研究

采用自制Fe—O／CeO2催化剂和正交设计试验方法,研究了微波催化氧化技术处理垃圾渗滤液的四个主要影响因素对COD去除率的影响,并得出处理工艺的最佳工况,结果表明：最佳处理工况为Fe-O／CeO2投加量10g／L,H2O2投加量22．5mL／L,微波功率800W,微波辐射时间8min,此时CODCr的去除率为69％。     

Bi2MoO6/AgBr的制备及其光催化活性增强机制

采用水热法合成了Z型异质结Bi₂MoO₆/Ag Br光催化剂,利用扫描电子显微镜(SEM)、X射线衍射仪(XRD)、比表面积测试仪(BET)、稳态/瞬态荧光光谱仪等对其微观形貌、物相组成以及光电性能等特性进行表征;通过对目标污染物罗丹明B(Rh B)的降解分析该催化剂的活性和降解机理。结果表明,该催化剂由立方相的Bi₂Mo O₆纳米片堆叠而成的纳米微球和负载在其表面的Ag Br纳米花簇构成,异质结的形成使得比表面积增加了7.2 m²/g,光生电子对寿命延长。Bi₂Mo O₆与Ag Br复合后光催化活性明显提高,当Ag Br复合量为10%时效果最佳,光催化反应速率常数是Bi₂Mo O₆的1.6倍。当Rh B浓度为0.5×10^-5mol/L、Bi₂Mo O₆/Ag Br投加量为250 mg/L、p H值=7时,反应20 min后对Rh B的降解率可达到95.9%,且Bi₂Mo O₆/Ag Br经过5次循环实验后仍具有较高的光催化活性。自由基捕获实验结果表明,Bi₂MoO₆的主要活性基为·O₂^-,Bi₂Mo O₆/Ag Br的主要活性基团为·O₂^-和h⁺。根据以上实验结果,提出了一种由Ag⁰粒子为通道的Z型电荷转移机理。     

Aged raw landfill leachate: membrane fractionation, O3 only and O3/H2O2 oxidation, and molecular size distribution analysis

Large molecular refractory organic compounds (i.e., humic substances) were the major chemical oxygen demand (COD) components of aged raw landfill leachate. To investigate the behaviours of the large molecular refractory organic compounds when they were subjected to oxidation with ozone only (O3 only) and ozone combined with hydrogen peroxide (O3/H2O2), the aged raw landfill leachate first was filtered with 0.8 and 0.45 microm pore size filters in series, then was sequentially fractionated with 10,000 MWCO; 5000 MWCO; and 1000 MWCO membranes, and four samples were formed: 0.45 microm-10,000 Da; 10,000-5000 Da; 5000-1000 Da; and < 1000 Da. Mass distribution profiles of COD, 5-day biochemical oxygen demand (BOD5), colour and metals in the aged raw leachate were developed through mass balance. After membrane fractionation of the aged raw leachate, the metals were fractionated with the humic substances. Each fractionated sample as well as the aged raw leachate was oxidised with O3 only and O3/H2O2. The H2O2 enhanced the reduction of COD and colour; while, the BOD5 after O3 only was always higher than that of O3/H2O2. The addition of H2O2 improved the peak reduction of large molecules, but the effects of H2O2 on the fractions of 10,000-5000 Da and 5000-1000 Da were likely insignificant, which is in accordance with the COD results. No correlation was found between the BOD5 increase and the area of new peak formed after oxidation. However, the BOD5 of each sample after oxidation with O3 only was the logarithmic function of its total peak area.     

Removal of refractory compounds from stabilized landfill leachate using an integrated H2O2 oxidation and granular activated carbon (GAC) adsorption treatment

This study investigated the treatment performances of H₂O₂ oxidation alone and its combination with granular activated carbon (GAC) adsorption for raw leachate from the NENT landfill (Hong Kong) with a very low biodegradability ratio (BOD₅/COD) of 0.08. The COD removal of refractory compounds (as indicated by COD values) by the integrated H₂O₂ and GAC treatment was evaluated, optimized and compared to that by H₂O₂ treatment alone with respect to dose, contact time, pH, and biodegradability ratio. At an initial COD concentration of 8000 mg/L and NH₃-N of 2595 mg/L, the integrated treatment has substantially achieved a higher removal (COD: 82%; NH₃-N: 59%) than the H₂O₂ oxidation alone (COD: 33%; NH₃-N: 4.9%) and GAC adsorption alone (COD: 58%) at optimized experimental conditions (p ≤ 0.05; t-test). The addition of an Fe(II) dose at 1.8 g/L further improved the removal of refractory compounds by the integrated treatment from 82% to 89%. Although the integrated H₂O₂ oxidation and GAC adsorption could treat leachate of varying strengths, treated effluents were unable to meet the local COD limit of less than 200 mg/L and the NH₃-N of lower than 5 mg/L. However, the integrated treatment significantly improved the biodegradability ratio of the treated leachate by 350% from 0.08 to 0.36, enabling the application of subsequent biological treatments for complementing the degradation of target compounds in the leachate prior to their discharge.     

TiO2/WO3纳米复合膜的制备及光催化性能研究

以有机染料亚甲基蓝(MB)为目标降解物,在玻璃基底上采用溶胶-凝胶法制备TiO2/WO3纳米结构复合光催化膜,研究不同TiO2和WO3摩尔比对性能的影响.采用XRD、SEM、EDS、UV-vis、电化学阻抗测试、光催化测试等技术对样品的成分及性能进行表征.结果表明,当TiO2和WO3摩尔比为3:1时,TiO2/WO3纳...     

Catalytic wet oxidation of phenol over a Pt/TiO catalyst

Wet oxidation of phenol by air or oxygen over a Pt/TiO₂ catalyst is studied in a batch reactor in the temperature range 150–200°C, pressure range 34–82 atm, and a catalyst loading range of 0–4 g catalyst L⁻¹. The catalyst was powdered 4.45% Pt/TiO₂ with a maximum particle size of 105 μm. Results show complete oxidation of phenol and almost complete total organic carbon (TOC) removal. Small amounts of stable organic acids are formed in side reactions of the phenol degradation pathway and are not readily degraded. Experimental results show that the reaction rate decreases by increased oxygen concentration. Theoretical rate expressions are derived, based on postulated oxidation and TOC reduction mechanisms.     

铁层柱蒙脱石处理垃圾渗滤液

采用铁盐水解聚合物为柱化剂改性钠基蒙脱石,制备了铁层柱蒙脱石催化剂,将其用于微波诱导催化处理经常规生化处理的垃圾渗滤液,进行深度处理。实验结果表明：初始COD浓度为1 100 mg/L～1 300 mg/L的垃圾渗滤液,以铁层柱蒙脱石作为催化剂,在微波功率600 W,辐照时间30 s条件下,经微波诱导催化处理后,COD去除率达到39%,并对微波作用机理进行了初步探讨。     

DEVELOPMENT OF AN ELECTROCHEMICAL OXIDATION PROCESS FOR THE TREATMENT OF LANDFILL LEACHATES

Some landfill site operators use wastewater treatment plants for the discharge of complex leachate waste. However, for the water company involved in managing the wastewater plant, leachates can pose a problem to the quality of the effluent, due to the high levels of Chemical Oxygen Demand (COD), ammonia and inorganic metal constituents. Electrochemical oxidation of landfill leachate has been successfully used by researchers^(1,2,3,4) with current densities of 5 to 100 mA/cm². A new laboratory system has been developed which utilises a low current density of 2.42 mA/cm² and the performance has been evaluated with synthetic and 'real' landfill leachates from 2 wastewater sites.
This system reduces COD of synthetic mixtures by 58%, with complete removal of ammonia. For real leachates, 5 out of 8 samples resulted in ammonia reduction, with 2 samples experiencing approximately. 60% COD reduction. Power costs for treatment have been determined and the potential for a full-scale installation considered.     

UASB/吹脱塔/SBR/纳滤工艺处理生活垃圾渗滤液

采用UASB/吹脱塔/SBR/纳滤工艺处理垃圾渗滤液,处理规模为800m3/d,垃圾渗滤液COD为8 000～12 000mg/L、BOD5为3000～5 500mg/L、SS为500～800mg/L、NH3-N为1 000～2 000 mg/L,出水COD≤l00mg/L、BOD5≤30 mg/L、SS≤30 mg/L、NH3-N≤25 mg/L,达到国家新建<生活垃圾填埋场污染控制标准>(GB 16889-2008).运行结果表明,该工艺运行稳定,处理效果好.