A review of catalytic processes for the destruction of PCDD and PCDF from waste gases

The current literature concerning the catalytic destruction of dioxins and of related model compounds is reviewed. Several different catalyst formulations have been tested, but V-rich vanadia-tungsta-titania catalysts seem to be mostly applied and allow reducing the dioxins concentration well below the limits of 0.1 ng TEQ/Nm³, as required by the EU directives. Other catalysts (in particular the noble metal-based ones) seem to be less efficient, due to deactivation effects and/or a considerable amount of polychlorinated by-products formation during oxidation activity. The coupled de-NO_x and dioxin destruction systems compete with activated carbon adsorption for efficiency in PCDD/F removal from gases.     

膜生物反应器+反渗透工艺对再造烟叶废水的处理

采用膜生物反应器(MBR)和反渗透(RO)组合工艺,深度处理再造烟叶生产的废水。结果表明:经"MBR+RO"处理后,废水的COD、色度、氨氮、浊度等的去除率均达到95%以上,RO出水(回用水)完全可以满足生产需要,部分指标优于生活饮用水。     

垃圾焚烧飞灰熔融过程二(口恶)英分解特性

引　言焚烧处理技术凭借其高效快捷和显著的减量效果在城市固体废弃物 (MSW )处理领域日益占有重要地位 .随着社会的进步和公众环保意识的逐渐提高 ,焚烧过程的二次污染尤其是二英的排放成为限制焚烧处理推广的瓶颈问题[1,2 ] .目前我国的垃圾焚烧过程排放二英限值为 1 0ng     

烧结烟气中NO x 和二英的减排现状及发展趋势

烧结工序是钢铁工业生产链的重要环节,同时也是大气中二氧化硫（SO₂）、氮氧化物（NO _x ）和二英的主要排放源。随着烧结烟气脱硫技术日趋成熟,氮氧化物和二英的减排成为烟气污染物减排的重中之重。本文介绍了钢铁工业烧结烟气超低排放的新法规和相关标准,并从源头控制、过程减排和末端治理三个方面综述了国内外关于烧结烟气中NO _x 和二英减排的最新研究进展及相关技术工业应用现状,提出了采用全流程多技术耦合方式是实现烧结烟气多污染物低成本减排的发展方向。结合钢铁工业“碳减排”新发展要求,指出烧结烟气低温脱硝/二英催化剂的研究挑战,并对其抗水、抗硫性能提升研究进行了展望。     

一种工业废气多污染物协同处理系统

本文介绍了一种工业废气多污染物协同处理系统,主要包括系统的工艺流程、平面布置和主要设备等内容。此外,本文还基于该系统在某水泥厂的运行试验数据,对其运行效果进行了评价。结果表明：在试验工况条件下,该系统对SO₂脱除率高于99%,NO_x脱除率为58.91%;同时,在试验工况条件下,系统也能实现颗粒物、氯化氢、二恶英的超低排放。因此,该系统对多污染物中的SO₂、颗粒物、氯化氢和二恶英均有较好的脱除效果,对NO_x的脱除效果仍有一定的提升空间。     

组合膜-表面活性剂法处理垃圾渗滤液中的氨氮

氨氮是《生活垃圾填埋污染控制标准》(GB 16889-1997)严格控制的、也是传统工艺难处理的一项指标。文中以北京市北神树垃圾填埋场渗滤液为研究对象,采用组合膜-表面活性剂法对其氨氮进行了处理。水样依次通过OSMONICS微滤EW膜和超滤GE膜后,调节膜出水pH值为6.5,加入质量分数0.02%的十二烷基苯磺酸钠(SD-BS),通过静电引力与NH4+形成大分子的复合态铵,然后经反渗透SE膜进一步处理。处理后的水样清澈透明,无异味,水质达到了GB 16889-1997的一级排放标准,氨氮去除率为99.4%。另外还探讨了水样的pH值、SDBS投加量等因素对氨氮去除率的影响。     

GC-MS法对垃圾渗滤液回灌处理前后有机成分的研究

利用模拟垃圾填埋装置进行渗滤液回灌处理的研究,取回灌处理后期的渗滤液与未经回灌处理渗滤液进行水质监测,并运用GC-MS联用技术对两种水样的有机成分进行对比分析。结果表明,羧酸类物质在检出物中所占比例较大,回灌处理对渗滤液中羧酸类物质的去除率达到61.26%,接近于CODC r的去除率59.65%。对一些毒害性物质也有一定的去除,哌啶类物质去除率为79.52%,呋喃的去除率为100%。     

Applications of reverse osmosis to complex industrial wastewater treatment

Methods for treatment of hazardous and complex, aqueous industrial wastes are of great current interest. Reverse osmosis (RO) has been shown to be an efficient and cost effective process step for renovation of a broad range of complex industrial wastes. The success of RO in large-scale desalination and municipal wastewater treatment has led many industries to view this technology as a means of pollution abatement and cost savings through reuse. Applications include renovation of effluents from the chemical, textile, petrochemical, electrochemical, pulp, paper and food industries. Also, treatment of landfill leachate with RO is showing promise as a means of avoiding groundwater and surface water contamination.     

基于硫基循环抑制技术的危险废物焚烧炉二(口恶)英排放的控制

依托某危险废物焚烧炉(50 t·d^-1)开发了一套硫基循环抑制及飞灰低温热处置联用控制二(口恶)英排放的中试平台,研究了该系统对硫基的循环累积能力及对烟气中二(口恶)英合成的抑制能力.系统利用吸附剂吸附了烟气中SO₂,并在低温热处置装置中将吸附剂中SO₂脱附回烟气中,实现SO₂循环.试验结果表明,该系统能连续稳定运行,对烟气中的SO₂具有一定的富集累积能力,添加一定量外源硫基物质后系统中烟气SO₂能维持在100 mg·m^-3左右,对整体二(口恶)英排放因子的去除率达80%以上.可见,该硫基循环抑制技术对废物处理过程中二(口恶)英减排具有重要指导价值,且长期稳定运行对控制二(口恶)英低排放起关键作用,但该中试系统的相关参数需进一步优化.     

反渗透处理橡胶工业废水的研究

本文采用低压中空醋酸反渗透装置和聚砜酰胺反渗透装置对齐鲁石化橡胶厂工业废水处理进行了试验研究。结果表明，反涌透对橡胶废水的总溶解固体，硬度，有同物都有较高的去除率，对总盐量的去除率稳定在８５％左右，百对可溶性ＳｉＯ２，和碱度去除率较低，试验表明和强水质的预处理是该废水处理的重要环节。     

电混凝-反渗透工艺处理垃圾渗滤液的试验研究

采用电混凝-反渗透组合工艺处理渗滤液经膜生物反应器的出水,考察组合工艺的处理效果及电混凝作为RO进水预处理的可行性。结果表明,组合工艺出水COD和NH3-N、TP的质量浓度分别为100 mg/L和20、0.2 mg/L,去除率分别达到95%、90%、98%,可以满足GB 16889-2008的排放要求;出水电导率为355μS/cm,膜出水电导率与进水电导率的比大于0.94。电混凝工艺能够有效降低RO进水的COD、TP含量,明显地减缓膜结垢污染,改善膜的产水率,可以作为膜前预处理。     

Contribution to solving the problem of dioxins generated during waste incineration

The production of dioxins/furans during waste incineration, and particularly the development of measures for minimizing the amount of generated pollutants, continue to command a considerable scientific as well public interest. Experiments are reported which were performed at the TAMARA municipal solid waste pilot incineration, erected on the premises of the karlsruhe Nuclear Research Centre. These experiments show that the solid waste mass flow rate and moisture content influence the dioxin/furan formation, Good removal efficiencies of dioxins/furans have been In wet cleaning. Hydrogen peroxide added to the crude gas is an interesting “killer” reagent for dioxins/furans.     

双膜法处理印染废水及其回用的工程应用

采用双膜法工艺处理某印染厂印染废水并回用,结果表明,系统运行良好,对COD的去除率达到了99%以上,对浊度、色度的去除率均接近100%,反渗透对盐分的去除率在98%以上。产水水质及水量稳定,满足回用印染要求,工程投资回报率高,经济和环境效益显著。     

Effectiveness in the Removal of Organic Compounds from Municipal Landfill Leachate in Integrated Membrane Systems: Coagulation – NF/RO

The article presents the results of studies concerning the hydraulic permeability of integrated membrane systems during the treatment of municipal landfill leachate. The laboratory-scale experiments were conducted to determine the effectiveness of coagulation as a pretreatment option for treating stabilized landfill leachate and effectiveness of nanofiltration (NF) and reverse osmosis (RO) processes. The municipal landfill leachates were analyzed for the concentration of the following: polycyclic aromatic hydrocarbons (PAHs), nitrate nitrogen, ammonium nitrogen, chemical oxygen demand (COD), total organic carbon (TOC), total carbon (TC), suspended soils (SS), turbidity, pH. The commercially available coagulant – aluminum sulfate Al₂(SO₄)₃·18H₂O (alum) was used as a coagulant. The NF process was carried out at the transmembrane pressure of 1.5 MPa. The membrane separation process was based on a thin film membrane (DK). The transmembrane pressure of the RO stood at 2 MPa and for this process one polyamide membrane (AG) was used. The level of leachate treatment was defined for raw and cleaned wastewater indicators. Both NF and RO membranes allowed obtaining the high level of pollutants removal. In the coagulation–NF system, the removal efficiency was equal to 77% for PAHs, 88% for COD, 72% for ammonium nitrogen, 80% for nitrate nitrogen, 67% for TOC, 80% for TC, 96% for SS and during the RO – 86% for PAHs, 98% for COD, 93% for ammonium nitrogen, 87% for nitrate nitrogen, 89% for TOC, 100% for TC, 98% for SS. The calculations based on the assumptions of the mathematical filtration model (relaxation) made it possible to predict the efficiency of commercial filtration membranes used for leachate treatment.     

渗沥液处理系统工艺设计思路分析

目前,国内渗沥液主要的处理工艺有以下几类:(1)生化系统+MBR+NF/RO;(2)厌氧/好氧+MBR+NF/RO;(3)MVC蒸发系统+DI。文章主要介绍生活垃圾填埋场渗沥液处理系统工艺的主体设计思路,并结合实际项目案例,分析处理工艺的处理效果以及运营阶段出现的问题。     

双氰胺-甲醛絮凝剂预处理垃圾渗滤液废水的实验研究

垃圾渗滤液成分复杂,废水有机物浓度高且水质水量变化较大,因此废水处理难度较大。本文以氯化铝、双氰胺、甲醛等为原料制备的新型双氰胺-甲醛絮凝剂用于济南某垃圾填埋场垃圾渗滤液的预处理试验,研究了双氰胺-甲醛絮凝剂对垃圾渗滤液预处理的可行性及处理的最优条件。试验发现,在pH为7,絮凝剂浓度为0．75g／L时双氰胺-甲醛絮凝剂对垃圾渗滤液的COD去除率可达到80-2％、对色度的去除率可达到90％。     

广东省生活垃圾渗滤液处理现状及处理对策研究

文章首先介绍广东省生活垃圾渗滤液水质情况及处理现状,其次,根据国内外最新研究进展,分析了广东省渗滤液的处理要求与处理难点,最后重点介绍MBR+NF+RO、MVC+DI、Fenton氧化+BAF等处理工艺,并分析工艺在广东的适用范围,以期为广东省生活垃圾渗滤液的处理对策提供建议。     

混凝+UF作为RO进水前处理的适用性研究

本文采用混凝＋UF作为RO进水的前处理,以颖河河水为原水进行了中试实验研究,考察了混凝剂投加量、曝气量、不同抽滤时间对超滤系统的影响.结果表明：混凝剂（PAC）投加量为14mg/L,曝气量为7.08L/s时,超滤对原水浊度的平均去除率为99.2%,出水SDI平均值为1.26,完全达到反渗透进水的水质要求,且水质稳定,混凝和超滤膜联用作为RO前处理是完全适用的.     

电路板清洗废水处理工程设计

采用"预处理系统+UF系统+RO系统"工艺对某印刷电路板公司的一般清洗废水处理回用。整个回用系统采用模块化组合,自动控制。系统稳定运行后验收,COD去除率达到90%以上,Cu2+的去除率大于99%,导电率由2000 s/cm降至150 s/cm,水的回用率也达到了业主要求。     

Effect of pH on the flotation performance of incinerator fly ash

Flotation was proved to be effective for decarburization and removal of dioxins from hospital solid waste (HSW) incinerator fly ash, but weathering makes it difficult. The effects of three types of surfactants including nonionic (Tween 80), anionic (SDS), and cationic (CTAB) at different pulp pH values on the flotation performance of weathered HSW incinerator fly ash were investigated. Results showed that the corresponding optimal pH values of Tween 80, CTAB, and SDS were 7, 5, and 9 in terms of decarburization performance, respectively, which were validated by the measurement of Zeta potential. The total dioxins and carbon removal efficiencies showed good correlation at various pulp pH values with surfactant of Tween 80. The optimum surfactant type and pH value should be selected as Tween 80 and pH = 7 from the standpoints of the dioxin removal. Under the optimum condition, the lowest content of dioxins (2.7 ng I-TEQ/g) in the tailings was obtained. The content of heavy metals in the froths exhibited higher with addition of SDS compared with that with Tween 80 and CTAB.