应用于垃圾渗滤液预处理工艺的研究

针对垃圾渗滤液高COD、高氨氮的特征,选用了混凝沉淀、Fenton氧化、蒸发及其组合工艺对垃圾渗滤液进行预处理,通过单因素试验,探讨了各工艺的最佳运行条件。试验结果表明,采用混凝沉淀法时,PAFC最佳投加量为30 mg/L,PAM最佳投加量为4 mg/L;采用Fenton氧化法时,H2O2最佳投加量为1.5‰,H2O2∶Fe2+最佳质量比为10∶3;垃圾渗滤液的最佳预处理工艺为混凝沉淀+Fenton氧化+蒸发,此时COD,NH4-N+的去除率分别为91.22%,86.73%,为后续生化处理提供了良好的反应条件。     

Fenton法处理垃圾渗滤液的影响因素分析

在半连续操作模式下进行了Fenton法处理垃圾渗滤液的试验。结果表明，用已建立的统计模型对早期渗滤兴的COD去除率进行预测时吻合程度较差。虽然渗滤液的TOC值也随Fenton氧化过程而降低，但其下降程度没有OCD显著，这是氧化过程中平均氧化状态升高所致。当Fe^2 的投量固定为0．44mol/L、H2O2与Fe^2 的投量比在2．86－7．03变化时，CDO的去除率变化大。当H2O2与Fe^2 的投量比固定为0时，COD的去除经随H2O2与初始COD摩尔比的升高而升高，并可超过80％。     

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.     

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。     

两级Fenton-BAF用于垃圾渗滤液深度处理工程

垃圾渗滤液经过常规工艺处理后,COD和TN仍然很高,难以达到排放标准。垃圾渗滤液生化处理出水COD约为1 500 mg/L,TN约为400 mg/L,采用两级Fenton-曝气生物滤池(BAF)组合工艺对垃圾渗滤液生化处理出水进行深度处理。双氧水加药量按照与COD的质量比为1∶1来控制,硫酸亚铁的投加量按照与COD的质量比为2∶1来控制,Fenton反应pH值控制在3左右,单级Fenton的反应时间控制在10 h。BAF脱氮反应的进水碳氮比控制在4∶1左右,单级BAF的停留时间约为2 d。实际工程运行结果表明:该工艺运行稳定,出水水质好,对COD与TN的去除率分别为96%和95%,出水COD和TN分别为60 mg/L和20 mg/L,达到了《生活垃圾填埋场污染控制标准》(GB 16889—2008)的表2标准。     

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。     

Fenton试剂处理垃圾渗滤液

为提高垃圾渗滤液的COD去除率,研究了Fenton试剂处理垃圾渗滤液过程中H2O2和Fe2＋的摩尔比、反应温度、pH值以及Fenton试剂的总加入量等条件对COD去除率的影响,研究发现：pH值约8.6,温度50 ℃,H2O2/Fe2＋为4,1.5倍化学计量需求量的Fenton试剂可以取得最高的COD去除率.     

UV/TiO2/Fenton光催化氧化垃圾渗滤液的研究

采用UV/TiO2与Fenton法的联合工艺处理垃圾渗滤液,考察了反应温度、pH值、TiO2投加量、H2O2用量等对COD去除率和脱色率的影响,比较了单一的Fenton法、UV/TiO2法和UV/TiO2/Fenton法处理垃圾渗滤液的效果.结果表明,反应温度越高,对垃圾渗滤液中COD的去除率和脱色率也越高;pH值为4时处理效果较好,pH值过低会抑制·OH的产生,pH值过高则水中胶体不易被去除,且Fe2+易失去催化活性;TiO2投加量需适当,TiO2过量会引起光散射,降低紫外光辐射效率;过量的H2O2会引发自由基链反应终止;UV/TiO2与Fenton试剂耦合,可促进TiO2表面羟基化,提高·OH的生成效率,加快自由基的链传递,提高对污染物的降解速率.     

UV/Fenton光催化氧化法处理液晶显示屏清洗废水

采用UV/Fenton光催化氧化法处理难生物降解、含高浓度表面活性剂的液晶显示屏清洗废水,考察了反应时间、亚铁盐及双氧水投加量、UV光强、体系pH、有机物初始浓度等对处理效果的影响。结果表明,当初始pH值为3~7.2时,经2 h左右的反应后可将废水的COD值由1 468 mg/L降至100 mg/L以下。对COD的去除率随反应时间的延长而增大并最终趋于平稳,合适的反应时间约为2 h。当H2O2与Fe2+的物质的量之比较低时,对COD的初始去除率较高。合适的FeSO4.7H2O投加量为543.5 mg/L,双氧水投加量为2.5~3 mL/L,且一次性投加即可。增加紫外光光强、投加TiO2等对有机污染物的去除有显著促进作用。     

TiO2、Cu2O和氧化石墨烯复合氧化垃圾渗滤液效能

针对垃圾渗滤液中成分复杂的污染物,在自然光照条件下,使用TiO₂/氧化石墨烯、Cu₂O/氧化石墨烯和TiO₂/Cu₂O三种复合催化剂分别对垃圾渗滤液原液进行催化氧化。结果表明,3种复合催化剂中,TiO₂/氧化石墨烯复合催化剂对有机物的去除效果最好,当催化剂与渗滤液COD的质量比为0.7时为该催化剂的最佳投加量,最佳反应时间为2 h。在最佳试验条件下,对垃圾渗滤液原液进行催化氧化后,对COD的去除率达到92.57%,此时渗滤液出水COD为964.79mg/L,出水NH4⁺-N为2015.84 mg/L,BOD₅/COD值达到0.83。     

Application of ferrous-hydrogen peroxide for the treatment of H-acid manufacturing process wastewater

1-Amino-8-naphthol-3,6-disulfonic acid (H-acid) is widely used in chemical industries for synthesis of direct, acid, reactive and azoic dye. The wastewater from H-acid manufacturing process is rich in various substituted derivatives of naphthalene and is one of the most hardly-treated wastewaters. A pretreatment method, ferrous ion-peroxide oxidation combined with coagulation, has been studied. The results have shown that the optimum pH value is below 4 and the suitable ferrous ion dosage is 200 mg/l. The COD removal of H-acid wastewater is about 50% and the residue have proved biodegradable when hydrogen peroxide dosage is 30 g/l. Ferrous ion-peroxide oxidation process can also improve efficiency of coagulation treatment. The overall COD removal can reach 90% or more when the concentration of ferrous ion is 200 mg/l, the dosage of hydrogen peroxide is 3 g/l and the ferric chloride dosage of two stage coagulation treatment is 15 g/l and 5 g/l, respectively. The groups on naphthalene ring, such as − + NO₂, SO⁻₃ etc., are substituted by hydroxyl free radical, and then the ring is broken down during oxidation process of H-acid.     

Application of ferrous hydrogen peroxide for treatment of DSD-acid manufacturing process wastewater

A pretreatment method for the biological treatment of wastewater from 4,4'-diaminostilbene-2,2'-disulfonic acid (DSD-acid) manufacturing processes, a refractory dye intermediate wastewater, based on combined ferrous hydrogen peroxide oxidation and coagulation-flocculation, was developed. When the wastewater was treated with ferrous hydrogen peroxide oxidation ([Fe2+] = 2.7 mmol/L, [H2O2] = 0.21 mol/L) after a flocculation using an organic flocculant TS-1 at a dosage of 3 g/L, the overall COD and color removals were 64 and 62%, respectively. BOD5/COD value of the effluent was 0.3. Ferrous hydrogen peroxide oxidation treatment can reduce the solubility of organic molecules with sulfonic group and increase the efficiency of coagulation treatment. The COD and color removals were both more than 90% when FeCl3 was used as the coagulation (dosages of two-step coagulation were 0.031 and 0.012 mol/L respectively) after a ferrous hydrogen peroxide oxidation pretreatment at a H2O2 dosage of 0.06 mol/L.     

微波强化Fenton氧化处理垃圾渗滤液的研究

以负载铁(Ⅱ)的颗粒活性炭(GAC)为催化剂,采用微波强化Fenton氧化处理老龄垃圾渗滤液,考察了对垃圾渗滤液的处理效果及微波的作用机理。结果表明,微波对Fenton氧化反应有催化作用,且可促进渗滤液中胶体的絮凝,微波作用时间是影响处理效果的主要因素;当GAC的铁负载量为33.32mg/g、微波功率为720W、微波时间为30min时,对COD和NH3-N的去除率最高,分别达到了95.64%和88.63%;COD主要通过催化氧化作用被去除,而NH3-N主要通过絮凝、吸附作用被去除;另外,微波可使GAC再生,提高了GAC的利用率。     

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。     

改性硅藻土处理垃圾渗滤液的中试研究

利用改性硅藻土对老龄垃圾填埋场渗滤液进行了处理,中试结果表明改性硅藻土的后处理效果比预处理效果好。若提高pH值、增加改性硅藻土投量还可提高COD去除率。采用两级硅藻土反应器串联处理老龄填埋场渗滤液生物处理出水,COD去除率可达到57%。     

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.     

高铁酸钾深度处理垃圾渗滤液的试验研究

采用自制的高铁酸钾深度处理垃圾渗滤液二级生化处理出水,考察了处理效果。结果表明,高铁酸钾投量、pH值和反应时间对COD和NH3-N的去除效果均有显著影响。当pH值为6,高铁酸钾投量为110 mg/L,反应时间为30 min时,对COD的去除效果最好;当pH值为8,高铁酸钾投量为125 mg/L,反应时间为24 min时,对NH3-N的去除效果最佳。渗滤液初始COD浓度低不利于高铁酸钾对COD的去除。     

AF-MBBR技术处理高盐垃圾渗滤液的试验研究

采用厌氧生物滤池一好氧移动床工艺（AF—MBBR）处理垃圾卫生填埋场高盐渗滤液。结果表明：好氧移动床生物反应器对渗滤液中的氨氮具有非常高的去除率；但高盐量对AF—MBBR去除COD产生了明显的抑制作用，致使对COD的平均去除率仅为22％。经研究发现从垃圾渗滤液中分离、筛选出的专性耐盐菌，对高盐渗滤液生物处理系统具有显著的强化作用。     

电解氧化处理垃圾渗滤液研究

采用电解氧化法对垃圾渗滤液进行深度处理的研究结果表明,电解氧化过程中,NH3－N优先于COD被氧化去除;SPR三元电极的处理效果优于DSA二元电极和石墨电极;酸性条件比碱性条件更有利于电解氧化作用对COD及NH3－N的去除;Cl^-浓度高时,有利于COD及NH3－N被氧化去除。试验得到的适宜电解氧化条件是：pH值为4、Cl^-浓度为5000mg/L、电流密度为10A/dm^2、SPR三元电极为阳极、电解时间为4h。当COD及NH3－N浓度分别为693mg/L和263mg/L时,COD去除率为90．6％,NH3－N的去除率为100％。