印染废水脱色技术与理论述评

文章介绍了印染废水典型脱色技术的现状和进展,并着重分析了各种脱色技术的脱色机制,突出了典型脱色训的理论因素,介绍并阐明了一些脱色理论新观点,如吸附剂改性增效原理、分子结构与絮凝效果的联系、小剂量氧化剂偶合絮凝、脱色菌的质粒对脱色率的影响等,并从工艺角度分析了各种脱色方法的应用。     

造纸废水治理技术研究现状及展望

介绍了造纸废水的各种处理技术：生物处理技术、絮凝沉淀法、过滤法、气浮法、造纸废水中主要碱回收技术、光催化氧化技术、人工湿地处理系统，并分析了治理技术的发展趋势。     

微生物絮凝剂L-3絮凝性能及废水处理研究

研究了影响微生物絮凝剂L 3絮凝活性的因素 ,并考察了其在染料废水处理方面的应用前景。结果表明 ,该絮凝剂絮凝膨润土悬浮液的最适宜pH值为 8,Ca2 + 、Mg2 + 等阳离子对其絮凝具有促进作用 ,对酸性湖兰A、碱性品红、活性翠绿KN R和直接深紫NM具有较好的脱色性能 ,脱色率分别达到 93%、84 2 %、75 5 %和 86 %。对赣州毛纺厂印染废水的处理结果为 :脱色率达 94 0 % ,COD去除率为 70 8%。     

微生物絮凝剂絮凝机理的研究方法

微生物絮凝剂是一种新型的絮凝剂,为了为微生物絮凝剂絮凝机理的研究提供全面、系统的研究技术,对微生物絮凝剂的絮凝机理,影响絮凝产生的因素进行了综述,并结合不断发展的现代生物技术与仪器分析技术,剖析了絮凝机理的各种研究方法,最后还提出了微生物絮凝剂絮凝机理的研究方向.     

微生物絮凝剂L-3絮凝性能及废水处理研究

研究了影响微生物絮凝剂L-3絮凝活性的因素，并考察了其在染料废水处理方面的应用前景。结果表明，该絮凝剂絮凝膨润土悬浮液的最适宜pH值为8，Ca^2 、Mg^2 等阳离子对其絮凝具有促进作用，对酸性湖兰A、碱性品红、活性翠绿KN-R和直接深紫NM具有较好的脱色性能，脱色率分别达到93％、84．2％、75．5％和86％。对赣州毛纺厂印染废水的处理结果为：脱色率达94．0％，COD去除率为70．8％。     

高色度印染废水和染料废水的脱色新技术应用

应用氧化絮凝复合新技术处理高色度印染废水和染料废水,研究了影响脱色效果的一系列物理化学因素。本技术应用于高色度印染废水和染料废水的脱色处理,可使其脱色率达99％以上,CODcr去除率也在80％以上。     

氧化-絮凝耦合处理酸性大红废水的机理研究

用氧化-絮凝耦合法处理酸性大红GR废水,以高锰酸钾为氧化剂、聚硅硫酸铁为絮凝剂,脱色率达到94.9%,COD去除率达到55.2%.通过用倒置式生物显微镜观察絮体,对反应机理进行推测.对高锰酸钾与酸性大红之间氧化还原反应产物和氧化-絮凝耦合处理的絮体进行紫外和红外吸收光谱扫描分析,探讨了氧化-絮凝耦合的反应历程和机理:酸性大红被高锰酸钾氧化成小分子有机物而脱色,还原产物新生态水合二氧化锰胶体吸附小分子有机物,并被聚硅硫酸铁卷裹成紧密絮体,氧化与絮凝之间产生协同作用,从而有效去除了色度和COD.     

新型复合聚铁硅絮凝剂处理生活污水的研究

采用新型的复合聚铁硅絮凝剂处理生活污水 ,通过混凝实验探讨了复合聚合硫酸铁硅PFSS、聚硅酸铁PSFS的脱色除浊、COD去除及氮、磷去除效果 ,并与常用的聚合硫酸铁PFS进行絮凝效果及经济成本的对比分析。结果表明 ,用复合型聚铁硅絮凝剂处理生活污水絮凝效果好 ,除浊率达 99%以上 ,脱色率 6 5 %～ 70 % ,COD去除率 70 % ,而且氮、磷去除效果好 ,成本低廉 ,具有较好的推广应用前景     

新型复合聚铁硅絮凝剂处理生活污水的研究

采用新型的复合聚铁硅絮凝剂处理生活污水，通过混凝实验探讨了复合聚合硫酸铁硅PFSS、聚硅酸铁PSFS的脱色除浊、COD去除及氮、磷去除效果，并与常用的聚合硫酸铁PFS进行絮凝效果及经济成本的对比分析。结果表明，用复合型聚铁硅絮凝剂处理生活污水絮凝效果好，除浊率达99％以上，脱色率65％～70％，COD去除率70％，而且氮、磷去除效果好，成本低廉，具有较好的推广应用前景。     

废润滑油絮凝脱色试验研究

废润滑油的回收再生利用不仅可以节约石油资源,而且是防治废润滑油污染、保护环境的主要措施.针对有污染的传统酸-白土废润滑油再生工艺,提出了以絮凝为主的无污染再生新技术,重点考察了影响废润滑油脱色再生效率的各种因素.结果表明,在絮凝剂用量为1.2%(体积分数)、搅拌时间为5 min、反应温度为75℃、沉降温度为80℃、沉降时间为2.0 h的条件下,废润滑油絮凝脱色效果最佳.废润滑油经过絮凝脱色和白土精制后理化指标得到了较大改善,基本接近该级别新油SC40的标准.     

印染废水混凝脱色技术的分子结构基础

印染废水的混凝脱色效果取决于染料分子的分子结构及其在水中的分子分散状态和染料的染色机制。大量研究结果表明，所选用的染料分子的分子结构决定了印染废水混凝脱色技术的混凝机制和混凝效果，合成絮凝剂与选择絮凝剂应充分考虑染料分子的分子结构与空间构型。     

亚铁羟基络合物还原转化水溶性偶氮染料

偶氮染料是印染工艺中应用最广泛的一类染料,目前染料废水脱色是污水处理难题。亚铁混凝处理染料废水过程中可能存在亚铁的还原作用,本实验制备了比溶解态亚铁更具还原反应活性的亚铁羟基络合物(ferrous hydroxycomplex,FHC),以5种不同类型的水溶性偶氮染料为目标污染物,研究FHC还原水溶性偶氮染料的脱色性能。实验结果表明,FHC对活性艳红X-3B、酸性大红GR和阳离子红X-GRL有较好的还原脱色效果,仅投加含铁89.6 mg/L的FHC,染料脱色率达到90%以上,继续增大FHC投加量可以完全脱色;中性枣红GRL的FHC还原脱色效果较差,需加入313.6 mg/L的FHC才能达到90%以上脱色率;134.4 mg/L的FHC能够将直接耐酸大红4BS完全脱色,但其脱色主要以混凝沉淀为主;溶液pH对FHC的还原性能产生重要影响,FHC还原染料脱色的适宜的pH值范围为4～10。该研究为亲水性染料脱色提供了一种新的技术,也为FHC运用于印染废水脱色提供了理论基础。     

陶瓷印花废水处理的混凝剂及工艺条件

采用混凝剂聚合氯化铝（PAC）、聚丙烯酰胺（PAM）、聚合硫酸铁（PFS）对陶瓷印花废水进行混凝沉降处理,监测水样的吸光度、浊度、悬浮物,以脱色率、浊度去除率、悬浮物去除率评价混凝处理的效果。结果表明：PAC是陶瓷印花废水沉降处理的理想混凝剂;水样的吸光度、浊度、悬浮物随混凝剂用量增大和沉降时间延长而呈降低趋势,而脱色率、浊度去除率、悬浮物去除率随混凝剂和沉降时间的增大呈增大的趋势;PAC投加量为20mg／L,沉降时间约为24h,水样脱色率达到90．0％,而当PAC投加量达到100mg／L,沉降时间约为4h,陶瓷印花水的脱色率可达到96．0％。证明了药剂用量的增加与沉降时间的延长对混凝过程具有增效作用。     

PFMS-PDMDAAC复合絮凝剂的制备及其絮凝性能

以硫酸亚铁、硫酸镁和聚二甲基二烯丙基氯化铵(PDMDAAC)为原料,制备了一种新型无机-有机复合絮凝剂PFMS-PDMDAAC,考察了碱化度、铁镁摩尔配比、有机絮凝剂与无机絮凝剂质量比(D/FM)和废水pH等对絮凝剂絮凝性能的影响,并应用于实际印染废水的处理。实验结果表明,PFMS-PDMDAAC在较宽的pH范围内有着良好的脱色性能,两者复配呈现出显著的协同作用,絮凝效果明显提高。在PFMS中引入PDMDAAC后,絮凝剂的Fe(Ⅲ)的优势形态含量增加;同时絮凝剂水解产物的Zeta电位亦明显升高,电中和能力增强。     

Functional group influences on the reactive azo dye decolorization performance by electrochemical oxidation and electro-Fenton technologies

Electrochemical water treatment technologies are highly promising to achieve complete decolorization of dyebath effluents, as demonstrated by several studies reported in the literature. However, these works are focused on the treatment of one model pollutant and generalize the performances of the processes which are not transposable since they depend on the pollutant treated. Thus, in the present study, we evaluate, for the first time, the influence of different functional groups that modify the dye structure on the electrochemical process decolorization performance. The textile azo dyes Reactive Orange 16, Reactive Violet 4, Reactive Red 228, and Reactive Black 5 have been selected because they present the same molecular basis structure with different functional groups. The results demonstrate that the functional groups that reduce the nucleophilicity of the pollutant hinder the electrophilic attack of electrogenerated hydroxyl radical. Thereby, the overall decolorization efficiency is consequently reduced as well as the decolorization rate. Moreover, the presence of an additional chromophore azo bond in the molecule enhances the recalcitrant character of the azo dyes as pollutants. The formation of a larger and more stable conjugated π system increases the activation energy required for the electrophyilic attack of ^?OH, affecting the performance of electrochemical technologies on effluent decolorization.     

Mechanism of decolorization and degradation of CI Direct Red 23 by ozonation combined with sonolysis

The decolorization and degradation of CI Direct Red 23, which is suspected to be carcinogenic, were investigated using ozonation combined with sonolysis. The results showed that the combination of ozonation and sonolysis was a highly effective way to remove color from waste water. The operational parameters, namely concentration of the dye, pH, ozone dose and ultrasonic density, were investigated during the process. The decolorization of the dye followed pseudo-first-order kinetics. Increasing the initial concentration of Direct Red 23 led to a decreasing rate constant. The optimum pH for the reaction was 8.0, and both lower and higher pH decreased the removal rate. The effect of the ozone dose on the dye decolorization was much greater than that of the sonolysis density. Intermediates such as naphthalene-2-sulfonic acid, 1-naphthol, urea and acetamide were detected by gas chromatography coupled with mass spectrometry in the absence of pH buffer, while nitrate and sulfate ions and formic, acetic and oxalic acids were detected by ion chromatography. A tentative degradation pathway was proposed without any further quantitative analyses. During the degradation, all nitrogen atoms and phenyl groups of Direct Red 23 were degraded into urea, nitrate ion, nitrogen and formic, acetic and oxalic acids, etc.     

Highly efficient decolorization of Malachite Green by a novel Micrococcus sp. strain BD15

Purpose

Malachite Green (MG) is used for a variety of applications but is also known to be carcinogenic and mutagenic. In this study, a novel Micrococcus sp. (strain BD15) was observed to efficiently decolorize MG. The purposes of this study were to explore the optimal conditions for decolorization and to evaluate the potential use of this strain for MG decolorization.

Methods

Optical microscope and UV?Cvisible analyses were carried out to determine whether the decolorization was due to biosorption or biodegradation. A Plackett?CBurman design was employed to investigate the effect of various parameters on decolorization, and response surface methodology was then used to explore the optimal decolorization conditions. Kinetics analysis and antimicrobial activity tests were also performed.

Results

The results indicated that the decolorization by the strain was mainly due to biodegradation. Concentrations of MG, urea, and yeast extract and inoculum size had significantly positive effects on MG decolorization, while concentrations of CuCl₂ and MgCl₂, and temperature had significantly negative effects. The interaction between different parameters could significantly affect decolorization, and the optimal conditions for decolorization were 1.0 g/L urea, 0.9 g/L yeast extract, 100 mg/L MG, 0.1 g/L inoculums (dry weight), and incubation at 25.2°C. Under the optimal conditions, 96.9% of MG was removed by the strain within 1 h, which represents highly efficient microbial decolorization. Moreover, the kinetic data for decolorization fit a second-order model well, and the strain showed a good MG detoxification capability.

Conclusion

Based on the results of this study, we propose Micrococcus sp. strain BD15 as an excellent candidate strain for MG removal from wastewater.     

Decolorization of direct dyes by salt fractionated turnip proteins enhanced in the presence of hydrogen peroxide and redox mediators

The present paper demonstrates the effect of salt fractionated turnip (Brassica rapa) proteins on the decolorization of direct dyes, used in textile industry, in the presence of various redox mediators. The rate and extent of decolorization of dyes was significantly enhanced by the presence of different types of redox mediators. Six out of 10 investigated compounds have shown their potential in enhancing the decolorization of direct dyes. The performance was evaluated at different concentrations of mediator and enzyme. The efficiency of each natural mediator depends on the type of dye treated. The decolorization of all tested direct dyes was maximum in the presence of 0.6mM redox mediator at pH 5.5 and 30 degrees C. Complex mixtures of dyes were also maximally decolorized in the presence of 0.6mM redox mediator (1-hydroxybenzotriazole/violuric acid). In order to examine the operational stability of the enzyme preparation, the enzyme was exploited for the decolorization of mixtures of dyes for different times in a stirred batch process. There was no further change in decolorization of an individual dye or their mixtures after 60 min; the enzyme caused more than 80% decolorization of all dyes in the presence of 1-hydroxybenzotriazole/violuric acid. However, there was no desirable increase in dye decolorization of the mixtures on overnight stay. Total organic carbon analysis of treated dyes or their mixtures showed that these results were quite comparable to the loss of color from solutions. However, the treatment of such polluted water in the presence of redox mediators caused the formation of insoluble precipitate, which could be removed by the process of centrifugation. The results suggested that catalyzed oxidative coupling reactions might be important for natural transformation pathways for dyes and indicate their potential use as an efficient means for removal of dyes color from waters and wastewaters.     

PAC混凝沉降法处理陶瓷废水操作条件的优化

采用PAC混凝沉降法对陶瓷废水进行处理,考察PAC用量、搅拌强度、搅拌时间、进水pH和沉降时间对处理效果的影响,获得优化的操作条件。实验表明:水样的脱色率、浊度去除率和悬浮物去除率随着PAC用量、搅拌强度、搅拌时间和沉降时间的增大和进水pH的降低而呈现增大的趋势;最佳操作条件为:当废水量小、处理时间充足时,选用PAC用量为12 mg/L、搅拌强度为中速、搅拌时间为10 min、进水pH为6、沉降时间为2 h,此条件下水样的脱色率、浊度去除率和悬浮物去除率分别达到95.6%、95.7%和85.6%;当废水量大、处理时间不充足时,选用PAC用量为60 mg/L,沉降时间为30 min,此条件下水样的脱色率、浊度去除率和悬浮物去除率分别达到94.1%、93.4%和84.4%。证明混凝法对于去除陶瓷废水中的悬浮与胶体颗粒均是有效的。     

日本大气污染和控制技术研究进展

本文详细地介绍了日本大气污染现状及其趋势,对主要污染物的污染状况进行了分析。概述了日本几十年来大气污染防治技术研究的进展。对改善燃烧、电子束法、NO_x处理触媒研究、NO_x吸附剂的研究、活性炭法干式脱硫、利用煤炭的干式脱硫、半干式简易脱硫、静电的应用、微生物的应用、电除尘、过滤除尘等大气污染防治技术的研究,做了详细介绍。对目前人们普遍关心的含氟气体排放控制问题进行了探讨。还简要介绍了日本大阪府等地,准备偿试的汽车排气总量控制的研究状况。