催化氧化活性炭除臭装置介绍

新型的催化氧化活性炭对硫化氢等臭味气体具有很强的催化氧化能力,并可通过水洗再生,克服了传统活性炭再生困难的缺点,且与其它除臭方法相比具有除臭效率高、运行管理方便等优势,是环保、市政等领域除臭的最先进技术之一。根据臭气浓度和气量的不同可设计不同类型的催化氧化活性炭除臭系统,以满足各类不同的除臭需求。     

臭味治理技术发展概况与展望

介绍了国内外臭味治理技术的发展概况,重点介绍了化学法除臭、活性炭法除臭、离子法除臭、催化氧化法除臭及生物法除臭的工作原理,并对每种方法的优缺点进行了说明。     

物联网技术在生物除臭工程中的实践应用

由于恶臭处理设施分散,且使用过程中缺少足够重视,除臭装置通常运行效率低下。本项目针对生物除臭设施运行中的常见问题,搭建了基于物联网的除臭系统远程智能监控平台,该系统由传感层、传输层和应用层构成,详细阐述了各层的实现方式与功能。在该系统上实现了异地污水厂分散除臭装置的统一监控,发挥了监控效益,实现了在线除臭装置的高效、节能运行和运行数据的有效收集,展现了物联网技术在除臭系统中应用的可行性与价值,为进一步拓开物联网在除臭领域的应用积累了重要经验。     

恶臭气体处理技术应用综述

本文对当前城市污水厂恶臭气体处理技术及其应用现状进行了综述,具体介绍应用于城市污水处理厂的生物除臭技术,离子除臭技术,化学吸收处理技术以及全催化除臭治理技术。分析表明,化学吸收技术对恶臭气体的处理简单易行,可操作性极强,但处理效率低;生物除臭技术对恶臭气体处理净化效果好,但设备运行对环境温度要求较为苛刻,该处理技术在北方低温环境应用受到局限;离子除臭技术对恶臭气体转化率高,但设备运行能耗高,且可能产生二次污染物;而全催化恶臭气体处理技术对恶臭气体中的硫化氢,有机硫组分去除率极高,运行费用低,无二次污染物生成,是一种经济高效且极具应用前景的除臭技术。     

某化工厂污水处理站除臭系统升级改造实例

工业园区恶臭治理迫在眉睫。本文以上海某化工厂污水处理站除臭系统升级改造工程为例，分析了原除臭系统在收集系统和处理工艺上的不合理之处，介绍了“两级生物滴滤+活性炭吸附”在化工厂污水处理站除臭治理中的应用。本工程案例中臭气仅通过两级生物滴滤处理，即可达到《上海市大气污染物综合排放标准》(DB31/933-2015)和《恶臭(异味)污染物排放标准》(DB31/1025-2016)中大气污染物的排放要求。活性炭作为保障工艺不投入使用，仅在异常工况时运行，节约活性炭资源。改造后的除臭系统全自动运行，节约人力资源，运行成本低。     

微波诱导活性炭催化氧化有机废水的研究进展

微波诱导活性炭催化氧化技术为有机废水处理提供了一种新的解决途径。全面阐述了该技术的催化氧化机理、微波反应器类型和处理效果,结合实际工程需求,对目前研究中存在的问题和发展趋势进行系统分析,以期为微波诱导活性炭催化氧化技术的工程化应用提供指导。     

催化氧化法处理两段炉废水

两段炉废水的处理方法和焦化废水的处理方法基本相同，是采用传统的隔油沉淀、气浮，然后进行生化处理和活性炭深度处理，但活性炭处理投资和运行成本较高，一般企业难以承担，所以不被选用。两段炉废水的处理较合理的方案是：隔油沉淀、气浮、调节池、生化处理、催化氧化法、外排。三相催化氧化法处理焦化废水和两段炉废水是一种新方法，气相是在催化氧化塔内鼓入空气，液相是氧化剂ClO２溶液，固相以活性炭为载体，以金属作为催化剂，这三相在常温常压下氧化有机污染物，将大分子有机污染物氧化分解成小分子有机物或二氧化碳和水，较好地…     

臭氧催化氧化-活性炭处理微污染源水

通过连续流试验比较了载锰颗粒活性炭催化臭氧氧化（催化氧化）与臭氧氧化及其后续活性炭过滤对微污染松花江水的处理效能。处理效率最高时,催化氧化对CODMn、UV254、DOC及三卤甲烷生成潜能的平均去除率分别为59.7%、75.8%、40.8%和42.4%,分别是臭氧氧化的3.6、1.4、5.0和2.8倍。随着时间的增加,催化氧化对有机物平均去除率下降,降低程度依次为：UV254〉CODMn〉DOC。催化氧化-活性炭工艺对水力负荷变化有较强的适应能力。臭氧氧化后水中氨氮浓度上升,而催化氧化后稍有下降,同时催化氧化后续活性炭对氨氮的平均去除率在80%左右,比臭氧氧化后续活性炭去除率高而且更加稳定。     

重质原油电脱盐污水深度处理中试研究

重质原油电脱盐污水生化性差、油含量高,采用双膜法对其进行深度处理时对预处理工艺要求高,同时膜过滤产生的浓水的处理也是后续处理的一大难题.中试采用自主研发的催化氧化工艺对浓水进行处理试验.结果表明:活性炭过滤+纤维束过滤或臭氧催化氧化预处理工艺均满足膜对污染物的控制要求;双膜系统运行稳定,浓水处理后达到国家一级排放标准,...     

高浓度双甘膦催化氧化合成草甘膦新工艺

研究了一种新的催化氧化合成草甘膦工艺.以高质量浓度的双甘膦、氧气为原料,活性炭为催化剂,55℃反应,利用高效液相色谱法有效监控反应终点,最后得到草甘膦合成液.草甘膦的收率94.5%,选择性达96.1%.     

常温下碳基活性材料催化氧化NO的研究进展

针对常温、含高浓度O₂ 的NO污染气体排放控制,典型的选择性催化还原（SCR）技术已不再适用。以碳基活性材料为催化剂的NO常温催化氧化技术得到了广泛关注,该技术在常温和高浓度O₂条件下将NO氧化为NO₂,并以硝酸或硝酸盐形式加以回收利用,因此具有环保和经济双重效益,应用前景广阔。本文简要综述了碳基活性材料常温催化氧化NO的研究进展,阐述了NO催化氧化机理,介绍了碳基活性材料的表面物化特性和反应条件（O₂浓度、NO浓度、GHSV、反应温度、水蒸气和催化剂粒径等）对催化氧化NO的影响,以及活性炭、活性炭纤维、碳纳米纤维、炭干凝胶、金属负载碳基活性材料、炭化污泥等不同碳基活性材料的催化特性,总结并展望了未来碳基活性材料低温催化氧化NO的发展方向。     

Oxidation inhibition effects of phosphorus and boron in different carbon fabrics

To improve oxidation inhibition, elemental boron and two phosphorus compounds were doped into an activated carbon cloth and a carbon felt. The hypothesis was that P can block active sites by virtue of the formation of C-P-O or C-O-P bonds at graphene edges while substitutional B can alter the chemical reactivity of the residual free active sites by reducing the electron density in the graphene layer. To increase the final dopant concentration, the carbon felt was activated in nitric acid. The crystallinity of activated carbon cloth was improved by heat treatment and substitutional B; that of carbon felt was also improved, but not necessarily due to substitutional B. In all cases the oxidation reactivity is suppressed by heat treatment and in the presence of dopants. The oxidation inhibition mechanism in P-doped samples appears to be active sites blockage because of a proportional increase of oxidation inhibition with increasing P loading. The results for B-doped samples are consistent with our previous studies in which B was found to exhibit both a catalytic and an inhibiting effect on carbon oxidation. Samples doped with both P and B showed the most effective oxidation inhibition and their oxidation behavior is described in detail.     

活性炭负载催化剂臭氧催化氧化处理印染废水研究

以堇青石蜂窝陶瓷、硅藻土、活性氧化铝和活性炭作为载体、金属氧化物(FexOy、CuO、NiO、MnxOy、BaO)作为催化活性组分,对臭氧催化氧化印染废水进行了试验对比,并对影响载铁型活性炭催化剂臭氧催化氧化印染废水的因素进行了研究。结果表明,载铁型的催化剂活性相对较高,当焙烧温度为750℃时,催化性能最好。利用载铁型活性炭催化剂,在臭氧质量浓度为10mg/L、pH值为6、反应时间为60min的条件下,催化氧化具有最佳的效果,COD去除率达86%;催化剂的重复利用性好,连续使用12次,COD的去除率仍可达64%。     

Hydrogen sulphide emission control by combined adsorption and catalytic combustion

The removal of low concentrations of hydrogen sulfide by adsorption and catalytic combustion has been studied. Concentration of hydrogen sulfide by adsorption from waste-gas streams is best effected by molecular sieve 13X, if the stream is dry, and by activated carbon, if the gas stream is moist.

Low-temperature catalytic oxidation of hydrogen sulphide in moist gas streams can be effected over activated carbon. The reaction appears to involve ionized hydrogen sulfide, dissolved in water condensed in the pores of the carbon.

At high temperatures, both supported platinum and palladium catalysts are found to be oxidation catalysts. Palladium is the best catalyst for methane oxidation but is partially deactivated in the presence of sulfur-containing gases. In contrast, platinum was more active for the same reaction in the presence of sulfur-containing gases.

Both metals were found to promote the oxidation of hydrogen sulfide above ca. 150°C. The power rate laws describing the kinetics of reaction were determined.     

活性炭催化剂臭氧催化氧化处理废水的研究进展

介绍了近年来国内外活性炭催化剂臭氧催化氧化的研究结果,对活性炭及金属负载型活性炭催化剂的反应机理进行了总结。讨论了非均相臭氧催化氧化过程中活性炭的主要作用,活性炭催化剂的表面物化性质、pH值、温度在臭氧催化氧化过程中的影响规律。并提出活性炭催化剂的降解机理以及催化剂性质与有机污染物的化学结构之间的关系还需要进一步的研究。     

Catalytic oxidation of carbon/carbon composite materials in the presence of potassium and calcium acetates

The catalytic effects of potassium acetate (KAC) and calcium acetate (CaAC) on the oxidation of carbon/carbon composites (C/C composites) used in aircraft brake system have been characterized. Potassium exhibited a very strong catalytic effect on the oxidation of the selected carbon samples, including C/C composite blocks impregnated with aqueous KAC solution and graphite powder physically mixed with KAC powder. The initial amount of catalyst loading and the pre-treatment in inert gas were found to affect its catalytic effectiveness. Impregnated calcium was also a good catalyst for the oxidation of C/C composites, but its effectiveness is much lower than that of potassium and is much less sensitive to catalyst loading amount and pre-treatment. Calcium acetate physically mixed with graphite powder only showed a slight catalytic effect. The experimental results suggested that the interfacial contact between catalyst and carbon is the key factor determining catalytic effectiveness, in agreement with previous studies using porous carbon materials. Due to its unique wetting ability and mobility on the carbon surface, potassium can form and maintain such contact with carbon and is, therefore, more effective in the C-O₂ reaction than calcium. The formation and development of such contact, which can also be affected by catalyst loading and pre-treatment process, can explain well the influence of these experimental conditions on the catalytic effect of potassium. The decreasing trend of reactivity with increasing burn-off in calcium-catalyzed oxidation is a result of interfacial contact loss because calcium does not have the necessary mobility to maintain such contact during reaction.     

Diesel fuel desulfurization with hydrogen peroxide promoted by formic acid and catalyzed by activated carbon

Desulfurization of diesel fuels with hydrogen peroxide was studied using activated carbons as the catalysts. Adsorption and catalytic properties of activated carbons for dibenzothiophene (DBT) were investigated. The higher the adsorption capacity of the carbons is, the better the catalytic performance in the oxidation of DBT is. The effect of aqueous pH on the catalytic activities of the activated carbons was also investigated. Oxidation of DBT is enhanced when the aqueous pH is less than 2, and addition of formic acid can promote the oxidation. The effect of carbon surface chemistry on DBT adsorption and catalytic activity was also investigated. Adsorption of DBT shows a strong dependence on carboxylic group content. The oxidative removal of DBT increases as the surface carbonyl group content increases. Oxidative desulfurization of a commercial diesel fuel (sulfur content, 800 wt. ppm) with hydrogen peroxide was investigated in the presence of activated carbon and formic acid. Much lower residual sulfur content (142 wt. ppm) was found in the oxidized oil after the oxidation by using the hydrogen peroxide-activated carbon-formic acid system, compared with a hydrogen peroxide-formic acid system. The resulting oil contained 16 wt. ppm of sulfur after activated carbon adsorption without any negative effects in the fuel quality, and 98% of sulfur could be removed from the diesel oil with 96.5% of oil recovery. Activated carbon has high catalytic activity and can be repeatedly used following simple water washing, with little change in catalytic performance after three regeneration cycles.     

Catalytic oxidation of sulfur dioxide on polyacrylonitrile-based active hollow carbon fiber

The catalytic oxidation of SO₂ on polyacrylonitrile-based active hollow carbon fiber (AHCF) was investigated. A single-pass reacting system was developed to study this reaction. The sulfur dioxide contained in the gas stream was oxidized to sulfuric acid in the presence of oxygen and water. Four types of active hollow carbon fibers were prepared through various conditions in order to study the influence of the structure of AHCF on the characteristics of the catalytic oxidation. The fiber sample with more mesopores and micropores showed a higher degree of reaction, but the degree of reaction declined after a period of time, possibly due to the saturation of the active sites by the reaction products. The degree of reaction from the fiber sample with fewer mesopores and micropores did not show the overshoot and reached a steady state after a period of time. © 1996 John Wiley & Sons, Inc.     

Inhibition of catalytic oxidation of carbon/carbon composites by boron-doping

The inhibition effect of high temperature boron-doping on the catalytic oxidation of carbon/carbon composites was investigated. Boron-doping at 2500 °C was found to improve the oxidation resistance of catalyst-loaded composites. Evident inhibition mechanisms include the reduction of active site number by increasing the crystallite size and the site blockage by formed boron oxide. Boron-doping at less than 1.0 wt.% was found to almost completely suppress the catalytic effect of calcium acetate after a slight carbon conversion. This inhibition effect was much less significant in the case of potassium-catalyzed oxidation where only a slight inhibition effect was observed. This is believed to be the essential result of the unique properties of potassium catalyst. Due to its wetting ability and mobility, potassium catalyst could form and maintain good interfacial contact with any exposed carbon surface regions.