真菌对染料废水脱色降解的研究进展

染料属生物难降解有机物，染料和印染废水已成为当前最重要的水体污染源之一。本文列举了近年发现和研究的染料脱色真菌，并综述了真菌脱色降解染料的机理及其在染料废水处理中的应用前景。     

染料降解菌的脱色特性、降解酶系及基因定位研究进展

本文分析了当前染料废水微生物降解优势菌的降解效果及降解机制等，介绍了三种染料降解酶的催化机理和影响因素，阐明了某些降解菌中的质粒可以控制不同结构染料的脱色。最终指出了提高菌株应用价值的两种途径：一是筛选或构建出具有多功能性的超级菌；二是在不改变染料性质的前提下，向其分子结构中引入特定取代基团，以提高其生物降解性。     

理化环境条件对青霉菌和细菌吸附脱色染料的影响

在筛选到的染料吸附脱色真菌和细菌的基础上，测定了温度和pH值对青霉G-1吸附和与细菌共培养脱色降解染料的影响。结果表明，16—36℃下青霉G-1对艳紫KN-B(C．I．Re．Vi．22)和黄M--3RE(C．I．Re．Ye．145)的吸附去除能力受温度影响不大，吸附5h去除率在97．1％--98．7％，而染料的脱色时间受温度影响较大，28—36℃下脱色速度快．青霉D1对pH3-11染料水中染料的吸附去除率高，达94．9％--97．8％，对pH13的吸附去除率低，仅为55．4％和56．2％，从pH5—13染料水中吸附染料的菌丝在与细菌共培养5—26h即完成了对染料的脱色，脱色速度较快。     

流动注射分光光度法研究离子强度对活性炭吸附阴、阳离子染料的影响

运用流动注射分光光度法，考察了不同离子强度(NaCl)下，在水溶液中表面带负电的活性炭分别吸附阴、阳离子染料的动力学行为。实验结果表明，对于所考察的2种阳离子染料和3种阴离子染料，活性炭的表观吸附速率常数均随着离子强度的增大而增大。这种加速吸附效应的出现，主要是因为离子强度的增大促进了活性炭表面与染料之间的非静电力作用。     

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。     

真菌和细菌对染料吸附脱色的高效共培养体系研究

在含有真菌G－1培养液中加入染料厂污水排放口的污泥样品，从发生快速脱色降解染料的混合培养液中分离出2株染料脱色细菌L－1和L－2，经API鉴定系统鉴定，确定菌株L－1为Enterobacter sp.，菌株L－2为Pseudomonas sp.,研究比较了单一和不同组合混合的真菌G－1菌株（Penicillium sp.)，细菌L－1菌株（Enterobacter sp.)和L－2菌株（Pseudomonas sp.)对偶氮染料红M－3BE（C.I.Reactive Red 241)和蒽醌染料艳蓝KN－R（C.I.Reactive Blue 19)的去除情况，发现G－1真菌和2种细菌组合的共培养体系对50mg/L红M－3BE和艳蓝KN－R处理5h去除率达100％和97．9％，并且是以脱色降解作用为主，建立了染料脱色降解菌的最佳组合，进一步测定了此最佳共培养体系对另外13种不同结构染料的脱色降解，结果表明，除对蒽醌染料R－478脱色降解较差外，对其他染料均可在1h-3d被完全脱色降解，表现出脱色降解染料的广谱性，向培养4d的共培养体系中依次加入8种染料，菌体可对染料连续脱色，维持脱色能力达8d左右。     

染料工业废水的治理方法

扼要介绍了中国染料工业现状及染炒废水特点，这了染料废水的治理方法，重点介绍了内电解法、氧化法、生化法等，同时也介绍了其他一些该当。     

白腐菌处理染料废水的研究进展

白腐菌是一种可有效处理染料废水的丝状真菌，它可通过其分泌的特殊的降解酶系或其他机制将各种人工合成的染料彻底降解为CO2和H2O，同时，对脱色具有良好的作用。本文就白腐菌的生物学特性及其对染料的降解酶系，机理和白腐菌发酵的主要影响因子，白腐菌处理染料废水的有关研究及应用现状进行了综述。     

新型氧化—混凝剂处理染料废水研究

根据染料废水的特点，研究了自制产品新型氧化—混凝剂处理染料废水的情况，探索了药剂用量、pH值等因素对COD、色度去除率的影响。试验表明，当PH＞10、“染清”氧化—混凝剂的加入量万分之三左右、絮凝时间6min、静置沉淀35min时，该药剂对染料废水具有良好的效果，COD和色度的去除率最高分别可达97％和86％，从而证明该方法对于染料废水的处理是可行的。该处理工艺设备简单，系统运行稳定，操作方便，成本低。     

动态强化微电解法处理染料废水及其机理的研究

模拟染料废水经动态强化微电解装置处理，其色度下降95％～98％，COD降低80％～85％。研究结果表明：其脱色机理主要是基于还原作用破坏了染料分子的不饱和共轭发色基团；COD的去除是还原后的染料分子结构发生了变化，导致可溶性降低，增强了悬浮胶体在以Fe^2 为胶凝中心的絮凝体捕集和吸附的共沉作用。     

Enhanced biodegradation of azo dyes using an integrated elemental iron-activated sludge system: I. Evaluation of system performance.

The objective of this research is to evaluate an integrated system coupling zero-valent iron (Fe(0)) and aerobic biological oxidation for the treatment of azo dye wastewater. Zero-valent (elemental) iron can reduce the azo bond, cleaving dye molecules into products that are more amenable to aerobic biological treatment processes. Azo dye reduction products, including aniline and sulfanilic acid, were shown to be readily biodegradable at concentrations up to approximately 25 mg/L. Batch reduction and biodegradation data support the proposed integrated iron pretreatment and activated sludge process for the degradation of the azo dyes orange G and orange I. The integrated system was able to decolorize dye solutions and yield effluents with lower total organic carbon concentrations than control systems without iron pretreatment. The success of the bench-scale integrated system suggests that iron pretreatment may be a feasible approach to treat azo dye containing wastewaters.     

Photocatalytic and combined anaerobic-photocatalytic treatment of textile dyes

A photocatalytic process based on immobilized titanium dioxide was used to treat crude solutions of azo, anthraquinone and phthalocyanine textile dyes. In addition, the process was applied to the treat autoxidized chemically reduced azo dyes, i.e. representatives of recalcitrant dye residues after biological sequential anaerobic-aerobic treatment. Photocatalysis was able to remove more than 90% color from crude as well as autoxidized chemically reduced dye solutions. UV-absorbance and COD were also removed but to a lower extent (50% in average). The end products of photocatalytic treatment were not toxic toward methanogenic bacteria. The results demonstrate that photocatalysis can be used as a pre- or post-treatment method to biological anaerobic treatment of dye-containing textile wastewater.     

Decolorization of dyes and textile wastewater by potassium permanganate

Decolorization of 10 types of dye solutions by potassium permanganate was studied. Effects of reaction conditions on the decolorization efficiency were examined in batch experiments. The pH value had a significant effect on the decolorization efficiency. When pH value <1.5, the decolorization efficiency was very high. When pH value >4.0, the dye solutions were almost not decolorized. Concentration of potassium permanganate and temperature also showed significant effects on the decolorization efficiency. The decolorization rate of dye solutions by potassium permanganate was rapid, and most of dye solutions can be decolorized effectively. The results of total organic carbon indicated that dye solutions were degraded incompletely by potassium permanganate. The results of treatment of textile wastewater by potassium permanganate indicated that the oxidation with potassium permanganate might be used as a pre-treatment process before biological treatment.     

物化技术处理高浓度染料废水的研究进展

由于染料废水具有成分复杂、浓度高、难降解等特点，对其有效处理一直是个难题。因此，综述了国内外的物理法、化学法，特别是高级氧化技术在处理染料废水中的进展情况，并指出物化技术和生物技术相结合的发展趋势。     

电-生物耦合技术对偶氮染料的去除研究

酸性大红GR是一种较难生物降解的偶氮染料,采用一种电场和生物耦合的新型技术处理酸性大红GR模拟废水,并与单纯电化学法和好氧生物法进行试验对照。结果表明：反应6 h后,电化学法、好氧生物法、电-生物耦合技术对酸性大红GR的去除率分别达到15.7%、25.8%和71.2%,电-生物耦合技术能明显提高酸性大红GR的去除效果,起到强化生物处理的作用。在15 mA微电流条件下电-生物技术能克服50 mg/L酸性大红GR对好氧生物处理的抑制作用,为高浓度难降解染料废水的生物强化处理提供了可能。     

Fenton氧化-生化组合工艺处理染料中间体废水

针对染料中间体废水具有COD高、BOD5/COD低和具有生物毒性的特性,采用Fenton氧化-水解酸化-好氧组合工艺进行染料中间体生产废水的处理试验,试验结果表明:废水经Fenton氧化及水解酸化工序后,废水的BOD5/COD值由0.03升高至0.48,经好氧生化工序处理后的出水COD和BOD5浓度分别达122.6 mg/L和54.6 mg/L,符合《污水综合排放标准》(GB8978-1996)二级标准,该组合工艺COD总去除率达94%.     

Biodegradability oriented treatability studies on high strength segregated wastewater of a woolen textile dyeing plant

Textile dyeing and finishing industry involves considerable amount of water usage as well as polluted and highly colored wastewater discharges. Biological treatability by means of mineralization, nitrification and denitrification of high strength woolen textile dye bathes, first- and second-rinses is presented. COD fractionation study was carried out and kinetic parameters were determined. Biodegradability of organic compounds in highly loaded composite wastewater after segregation and the effluent of applied biological treatment of high strength composite wastewater were measured by determining oxygen consumption rates. The results were used in terms of assessing an alternative method for inert COD fractionation. The study implied that about 80% soluble COD, 50% color and 75% toxicity reduction were possible by single sludge biological processes. Sixteen per cent of total COD was found to be initially inert. Inert fraction was increased to 22% by production of soluble and particulate microbial products through biological treatment.     

Effect of textile auxiliaries on the biodegradation of dyehouse effluent in activated sludge

The textile industry is confronted with serious environmental problems associated with its immense wastewater discharge, substantial pollution load, extremely high salinity, and alkaline, heavily coloured effluent. Particular sources of recalcitrance and toxicity in dyehouse effluent are two frequently used textile auxiliaries; i.e. dye carriers and biocidal finishing agents. The present experimental work reports the observation of scientific and practical significance related with the effect of two commercially important textile dye carriers and two biocidal finishing agents on biological activated sludge treatment at a textile preparation, dyeing and finishing plant in Istanbul. Respirometric measurements of the dyehouse effluent spiked with the selected textile chemicals were carried out for the assessment of the "readily biodegradable COD fraction" of the wastewater. The respirometric data obtained to visualize the effect of the selected textile auxiliaries on biomass activity was evaluated by an adopted activated sludge model. Results have indicated that the tested biocides did not exert any significant inhibitory effect on the treatment performance of the activated sludge reactor at the concentrations usually encountered in the final, total dyehouse effluent. The situation with the dye carriers was inherently different; one dye carrier appeared to be highly toxic and caused serious inhibition of the microbial respirometric activity, whereas the other dye carrier, also known as the more ecological alternative, i.e. the "Eco-Carrier", appeared to be biodegradable. Finally, the respirometric profile obtained for the Eco-Carrier was described by a simplified respirometric model.     

The effect of pre-ozonation on the biocompatibility of reactive dye hydrolysates

Pre-ozonation of 14 different reactive dyestuff hydrolysates at alkaline pH was investigated to assess possible relationships between ozone transfer efficiency, first order decolourization kinetics, release of initially complexed heavy metals and relative changes in the biodegradability of the partially oxidized dye waste samples. Biocompatibility of the raw (untreated) and ozonated dye hydrolysates was comparatively tracked through specific oxygen uptake rate measurements from which the respirometric inhibition of biological activated sludge imparted by raw and ozonated reactive dye wastewater with respect to synthetic domestic wastewater was determined. It could be demonstrated that preliminary ozonation of reactive azo dyes increases their biological compatibility more significantly than formazan copper complex, copper complex azo and phythalocyanine dyes as a consequence of heavy metal release associated with the cleavage of associated chromophoric groupings right at the initial stages of pre-ozonation.     

Decolorization and biodegradation of dye wastewaters by a facultative-aerobic process

BACKGROUND: Dye wastewater is one of the main pollution sources of water bodies in China. Conventional biological processes are relatively ineffective for color removal, the development of alternative treatment methods will become important. Our subjective was that of introducing a new biotreatment technology which combined a facultative biofilm reactor (FBR) with an aerobic reactor (AR) to treat a dye wastewater. The efficiencies of color and chemical oxygen demand (COD) removal and the mechanism of dye degradation were investigated. METHODS: The anthraquinone acid dye (acid blue BRLL) concentration, organic loading rate (OLR) and hydraulic retention time (HRT) were varied in the experiments to evaluate the treatment efficiency and process stability. The biodegradation products were detected by infrared (IR) and high performance liquid chromatography and mass spectrometry (HPLC-MS). RESULTS AND DISCUSSION: The results demonstrated that the facultative biofilm process was more effective for decolorization than the anaerobic stage of an anaerobic-aerobic process. Most color removal occurred in the facultative reaction (maximum to 88.5%) and the BOD (biochemical oxygen demand): COD of the FBR effluent increased by 82.2%, thus improving the biodegradability of dyes for further aerobic treatment. The dye concentration, OLR and HRT will be the factors affecting decolorization. Color removal efficiency falls as the influent dye concentration increases, but rises with increased HRT. The infrared and HPLC-MS analyses of the effluents of FBR and AR reveal that the dye parent compound was degraded in each reactor during the process. CONCLUSION: The Facultative-aerobic (F-A) system can effectively remove both color and COD from the dye wastewater. The FBR played an essential role in the process. The average overall color and COD in the system were removed by more than 93.9% and 97.1%, respectively, at an OLR of 1.1 kg COD m(-3) d(-1) and at the HRT of 18-20 hours in the FBR and 4-5 hours in the AR. The color removal mechanism in each reactor was not only a sort of biosorption on the floc materials, but even more an effect of biodegradation, especially in the facultative process. Recommendation and Outlook. In applying the F-A system to treat a dye wastewater, the control of facultative processes and the set up of appropriate operation conditions appear to be critical factors. Also, it is suggested a moderate COD loading rate and about a 24-hour HRT will favor the F-A system.