零价铁及其复合工艺降解印染废水的应用研究

印染废水因具有高色度、高有机物浓度、难生物降解的独特性质,一直是国内外环境领域关注的重要水体污染源之一。零价铁由于其独特的性质,已成为国内外研究处理印染废水的主要方向之一。介绍了零价铁的研究现状,分析了零价铁降解印染废水的作用机理、动力学及影响因素,着重介绍了近几年新兴的几种零价铁与其他水处理技术联用的复合工艺对印染废水的降解作用。最后,对现存的一些技术问题进行了讨论。     

零价铁法处理染料废水脱色效果研究

本文研究了零价铁降解染料废水的工艺条件:如pH值、搅拌时间、铁屑投加量,并在最佳工艺条件下处理了直接大红?直接艳红?活性红混合染料废水,色度去除率达98.83%;探讨了零价铁处理染料废水的机理。     

零价铁处理含铀废水的试验研究

就零价铁处理含铀废水进行了试验研究,考察了pH、震荡时间、静止时间、铁的投加量等因素对铀去除率的影响,得到了最佳实验条件.通过试验对比了铁粉和废铁屑对铀废水的处理效果,发现废铁屑比铁粉对铀的去除率更高.最后分析探讨了铁粉和废铁屑对废水中铀的去除机理,指出零价铁对废水中铀的去除符合Langmuir吸附规律.     

超声降解染料废水研究进展

本文介绍了超声降解的机理、影响因素以及在研究染料降解中取得的成果,主要包括超声波与臭氧、光降解、Fenton试剂、生物法、磁化学、零价铁及电化学氧化技术的联用,并对超声处理染料废水技术的发展趋势提出了见解。     

零价铁联用技术处理废水的研究进展

零价铁联用技术结合零价铁和其他技术优点去除水中难降解有机污染物、重金属、放射性物质等多种污染物,克服了零价铁单独使用易被氧化、去除效率低等缺点,提高了废水处理效果。主要介绍了当前常见的几种零价铁联用技术:零价铁-PRB技术、零价铁-过硫酸盐技术、零价铁-微生物技术、零价铁-Fenton技术,分析零价铁联用技术当前研究进展、作用机理、应用中存在问题,指出如何将纳米零价铁与相关技术联用进行常规水处理,或针对处理某种难降解污染物,将是未来零价铁体系新的研究方向。     

纳米级金属铁还原脱氯技术的改进研究

零价铁处理环境中有机卤化物、重金属等污染物是目前公认的一种有效的环境修复技术,具有良好的应用前景。但无论是金属铁可渗透反应墙还是铁纳米颗粒原位注射技术都存在缺陷,对零价铁反应性能的改进十分迫切。文章综述了国内外对零价铁反应性能改进的研究进展,详细介绍了当前最热门的铁纳米颗粒负载技术及铁纳米颗粒分散稳定技术对零价铁反应性能的改进机理及优势,指出了目前研究存在的一些问题,并对零价铁技术修复环境的工程应用提出了展望。     

纳米零价铁的制备及其对废水中铬的去除作用研究

采用液相还原法制备了纳米零价铁材料,借助扫描电镜对制备材料进行了微观形貌分析。利用制备的纳米零价铁对配制含铬废水的处理效果进行了考查,探究了纳米零价铁投加量、废水中Cr(Ⅵ)初始浓度、废水初始pH值及反应时间对Cr(Ⅵ)去除率的影响。实验结果表明使用该纳米零价铁处理含铬废水的最佳工艺条件为:废水中Cr(Ⅵ)初始浓度为20 mg/L、纳米零价铁投加量为500 mg/L、废水初始pH值为3、反应处理时间为4.5 h。在最佳工艺条件下Cr(Ⅵ)的去除率可达99.45%。     

负载型纳米零价铁复合材料去除U(Ⅵ)的研究现状

近年来,纳米零价铁在治理含铀废水得到了广泛的应用,但是纳米零价铁本身易团聚、易失活和易造成二次污染使它的应用前景得到了限制。因此,国内外研究学者针对其缺点研究出了负载型纳米零价铁,这一技术从根本上提高了了纳米铁的稳定性和分散性,防止纳米零价铁的团聚和失活,提高了纳米零价铁的反应性能从而更高效的去除了含铀废水中的铀。总结了负载型纳米零价铁的制备方法以及国内外应用负载型纳米零价铁治理含铀废水的研究进展,并对负载型纳米零价铁在修复环境中铀污染的工艺中存在的问题以及今后的发展路线提出了建议。     

添加零价铁的反硝化系统中发生的主要反应

分别采用零价铁、反硝化污泥及零价铁+反硝化污泥的系统处理含NO_3~--N的废水,探讨零价铁的添加对反硝化系统脱氮效果的影响及系统中发生的主要反应。结果表明,零价铁系统对废水中的NO_3~--N无去除效果;当零价铁+反硝化污泥系统对废水中NO_3~--N的去除率达到100%时,反硝化污泥系统对废水中的NO_3~--N去除率仅为60.1%。零价铁+反硝化污泥系统中主要发生零价铁参与的氧化还原反应及微生物参与的生物反硝化反应。     

零价铁降解地下水卤代烃技术研究进展

随着卤代烃类有机污染物越来越多地出现在自然水体中,卤代烃降解工艺的研究也越来越受到人们的重视。该文简述了卤代烃的物理性质以及用途,与零价铁有关的处理卤代烃的相关工艺如零价铁还原、纳米零价铁技术、零价铁-氧化剂联用技术、零价铁-厌氧微生物技术等,展望了零价铁技术的发展前景。     

零价铁及其耦合技术强化抗生素废水的处理

抗生素被广泛应用于治疗疾病、畜牧养殖业及病虫害防治等,然而抗生素大规模的生产及使用,对生态系统造成了持久性破坏。同时,未完全降解的抗生素在环境中逐步积累,导致抗生素抗性基因（ARGs）的富集,对环境造成极大的威胁,因此亟待开发经济、高效且可削减ARGs的抗生素处理方法。零价铁（ZVI）因廉价、易操作、不产生二次污染,被广泛用于含难降解污染物的污水处理过程,并在抗生素废水的处理中进行了广泛研究。本文从ZVI及其耦合技术对抗生素的作用机制与ZVI对厌氧消化的影响等方面,综述ZVI及耦合技术在处理抗生素废水中的应用。文章指出,ZVI主要通过产生羟基自由基（·OH）氧化降解抗生素,此外ZVI被腐蚀后形成的氢氧化物、氧化物也可吸附去除大量抗生素。零价铁-光芬顿与零价铁-电芬顿耦合工艺分别通过光能与电能促进·OH的产生,并实现Fe²⁺的循环利用。ZVI耦合厌氧生物处理过程中,ZVI可优化微生物群落,提高酶活性,从而促进厌氧消化降解抗生素,并削减部分ARGs。针对以上工艺特点,合成廉价高效的ZVI材料、探索ZVI对厌氧消化过程中ARGs的削减机制将是ZVI及其耦合技术强化抗生素废水处理的研究重点。     

Performance of a ZVI‐UASB reactor for azo dye wastewater treatment

BACKGROUND: Zero valent iron (ZVI) is expected to be helpful for creating an enhanced anaerobic environment that might improve the performance of the anaerobic process. Based on this idea, a ZVI packed upflow anaerobic sludge blanket reactor (ZVI‐UASB) was developed to enhance azo dye wastewater treatment. RESULTS: The ZVI‐UASB reactor was less influenced by a decrease in the operational temperature from 35 °C to 25 °C than a reference UASB reactor that did not contain ZVI. In addition, chemical oxygen demand (COD) and color removal efficiencies of the ZVI‐UASB reactor at an HRT of 12 h exceeded those of the reference reactor at an HRT of 24 h. The hydraulic circulation in the ZVI bed enhanced the function of ZVI so that it improved the COD and color removal efficiencies. Moreover, fluorescence in situ hybridization experiments revealed that the abundance of Archaea in the sludge of the ZVI bed was significantly higher than that at the reactor bottom, which made the reactor capable of greater COD removal under low temperature and short HRT conditions. CONCLUSION: This ZVI‐UASB reactor could adapt well to changes in the operational conditions during wastewater treatment. Copyright © 2010 Society of Chemical Industry     

Reductive transformation and dechlorination of chloronitrobenzenes in UASB reactor enhanced with zero‐valent iron addition

BACKGROUND: Zero‐valent iron (ZVI) is increasingly being applied in biological wastewater treatment to enhance the conversion of various contaminants. The objective of this present study was to investigate the effect of ZVI on the anaerobic biotransformation and dechlorination of chloronitrobenzenes (3,4‐DClNB and 4‐ClNB). Experiments were conducted in two upflow anaerobic sludge blanket (UASB) reactors, one (R2) with 30 g L^?1 ZVI added, and the other (R1), serving as control reactor. RESULTS: ZVI‐based anaerobic granular sludge (ZVI‐AGS) composed of bacteria associated with precipitated FeCO₃ and FeS was successfully developed within 5 months in reactor R2. ZVI addition obviously enhanced 3,4‐DClNB transformation and dechlorination efficiencies under high 3,4‐DClNB loads, and further promoted dechlorination of 4‐chloroaniline (4‐ClAn) to aniline. Compared with the AGS formed in R1 reactor, iron and its corrosion products were observed and colonized with anaerobes such as methanothrix in ZVI‐AGS, and the specific transformation rates of 3,4‐DClNB and 4‐ClNB using ZVI‐AGS were improved by 34.0% and 64.4%, respectively. Furthermore, ZVI‐AGS provided higher 3,4‐dichloronailine and 4‐ClAn dechlorination efficiency than AGS. Abiotic transformation of ClNBs by ZVI, appropriate concentration of iron corrosion products, lower redox potential and greater hydrogen production were the main factors providing enhanced transformation and dechlorination of ClNBs in the UASB reactor. CONCLUSION: Addition of ZVI to a UASB reactor enhanced the reductive transformation and dechlorination of ClNBs. It provides a feasible proposal for the design and optimization of a high‐rate anaerobic wastewater treatment technique for industrial wastewater. Copyright © 2010 Society of Chemical Industry     

零价铁促进厌氧微生物降解喹啉效能的研究

对比考察了厌氧生物处理(AD)、ZVI处理和ZVI-AD协同处理对喹啉的处理效果。结果表明,ZVI能够明显促进厌氧微生物降解喹啉的能力。通过考察协同体系中p H和ZVI投加量对降解喹啉的影响,得出体系的最佳p H=7.5,ZVI投加质量浓度3 g/L。在最佳试验条件下,处理96 h时,喹啉降解率可提高到80.5%,而甲烷产量比单独AD处理提升2.4倍。     

工业废水中锑的检测和治理方法研究进展

随着含锑产品的生产和广泛应用,大量含锑工业废水直接排放到环境中,严重污染了环境,对人体健康也造成危害。因此,工业废水中的锑的测定方法和除去方法研究日益受到重视,本文对近年来工业废水中锑的检测和治理方法的研究进展作一简要概述。     

循环式活性污泥法的工艺特性及其应用

介绍了循环式活性污泥法(CAST)的工作原理，概述了国内外关于循环式活性污泥法在城市及工业废水处理中的操作运行条件及实际应用现状。认为循环式活性污泥法将SBR工艺和生物选择器的原理结合在一起，具有防止污泥膨胀、强化脱氮除磷效果、耐冲击负荷等显著特点。在城市生活污水、工业有机废水，尤其是含氮、磷工业废水处理中有良好的研究开发价值和广阔的推广应用前景。     

Enhanced biodegradation of 2‐chloronitro‐benzene using a coupled zero‐valent iron column and sequencing batch reactor system

BACKGROUND: This study focused on the effectiveness of the zero‐valent iron (ZVI) pre‐treatment for enhancing the biodegradability of 2‐chloronitrobenzene (2‐ClNB), and further to evaluate the performance and mechanism of a coupled ZVI column–sequencing batch reactor (SBR) system treating 2‐ClNB contained wastewater. RESULTS: 2‐ClNB was readily transformed into 2‐chloroaniline (2‐ClAn) with the efficiency over 99.9% by ZVI column, and its biodegradability was significantly enhanced via ZVI pretreatment. The transformed effluent was subsequently fed into the SBR followed by 2‐ClAn loading of 3.4–117.2 g m^?3 d^?1 and COD loading around 1000 g m^?3 d^?1. A 2‐ClAn removal efficiency over 99.9% and COD removal efficiency of 82.0–98.1% were obtained. Moreover, 91.9 ± 0.1% TOC removal efficiency and 107.1 ± 6.0% chloride recovery efficiency during one cycle confirmed the complete biodegradation of 2‐ClAn in the coupled system. 16S rDNA PCR‐DGGE analysis suggested that ZVI pretreatment enhanced the diversity of the microbial community and promoted enrichment of the functional microorganisms degrading 2‐ClAn in the following SBR. CONCLUSION: ZVI pretreatment significantly enhanced the biodegradability of 2‐ClNB, and the coupled ZVI–SBR system demonstrated excellent performance when treating wastewater containing 2‐ClNB. Copyright © 2011 Society of Chemical Industry     

GC-MS解析炼化污水中挥发性有机物组成和变化

对西北某大型炼化企业炼油、化工两条污水处理流程的关键工艺环节进行水样采集,采用紫外可见光谱及吹扫捕集-气相色谱与质谱联用（GC-MS））解析了污水水样中挥发性有机成分的组成和含量的变化。共鉴定出有机物19类76种,化工污水当中的有机物（43种）相对炼油污水（32种）更加复杂。研究表明,炼油污水含较多的含硫化合物（硫醚、噻吩）,是恶臭气体的主要来源;化工污水含较多的含氮化合物（硝基化合物、腈类、氰类）,是氨氮及总氮的主要贡献者;芳香化合物种类多达数十种,对VOCs贡献较大。指出化工污水水解环节可产生部分醇、酮类化合物,提高后续污水可生化性。生化处理环节能去除污水中的绝大部分烷烃、烯烃、炔烃和少部分醇、酮;而芳香烃、多环芳烃、氯代烃生物降解性相对较差,生化后依旧具有残留,是污水处理COD残留的重要原因,可作为炼化特征有机污染物。提出分子水平的精细解析,能够为污水处理工艺评价提供科学依据,进而对工艺开发和工艺改进提供帮助。     

Capacity of Cr(VI) reduction in an aqueous solution using different sources of zerovalent irons

Zerovalent iron (ZVI) has drawn intense interest as an effective and inexpensive tool to enhance degradation of various environmental contaminants. Reduction of Cr(VI) to Cr(III) by ZVI merits environmental concern as a hazardous species is transformed into a non-hazardous one. Objectives of this research were to assess kinetics and capacity of Cr(VI) reduction by different sources of ZVIs, of which chemical parameters can base in situ application of ZVI to treat Cr(VI) contaminated water. Reduction kinetics were first-order and rapid showing that 50% of the initial Cr(VI) was reduced within 7.0 to 347 min depending on Cr(VI) concentration, temperature and ZVI source. The reduction rates were increased with decreasing the initial Cr(VI) concentrations and increasing the reaction temperatures. The J ZVI (Shinyo Pure Chemical Co., Japan) was more effective in Cr(VI) reduction than PU (Peerless Metal Powders, USA). The maximum reduction capacities of J and PU ZVIs at 25°C were 0.045 and 0.042 mmol g⁻¹ Fe⁰, respectively. A relatively higher value of the net reaction energy (E _a ) indicated that Cr(VI) reduction by ZVI was temperature dependent and controlled by surface properties of ZVI. Chemical parameters involved in the Cr(VI) reduction by ZVI such as temperature quotient, kinetic rates, and stoichiometry indicated that the ZVI might be effective for in situ treatment of the Cr(VI) containing wastewater.     

纳米TiO2光催化降解含活性红K-2BP染料废水技术研究

本文以纳米二氧化钛为光催化剂,采用自制的间歇式悬浆体系光催化反应器对活性红K-2BP染料模拟废水进行光催化降解试验,考察废水pH值、初始浓度等因素对反应的影响,在试验条件下,染料模拟废水的COD去除率可达70%以上,反应后废水可生化性提高,其光催化降解反应符合Langmuir-Hinshewood模式,光催化氧化法是处理难降解染料废水的有效方法。