Decolourization of textile dyes by the white‐rot fungi Phanerochaete chrysosporium and Pleurotus ostreatus

BACKGROUND: The ability of the fungi Pleurotus ostreatus and Phanerochaete chrysosporium to decolourize and detoxify 11 (mono‐, dis‐, poly‐ azo, and anthraquinonic type) dyes, widely used across the textile and leather industries, was tested. RESULTS: Different substrate specificities were revealed between P. ostreatus and P. chrysosporium in decolourization experiments. The latter fungus provided almost complete decolourization of the tested azo dyes up to 600 ppm and dis‐azo dyes up to 1000 ppm, and 80% decolourization of the tris‐azo dye DBU1L38 at 1000 ppm, after 6 days. P. ostreatus provided almost total decolourization of the anthraquinone type dye ABU62 (1000 ppm) after just 1 day. P. ostreatus also showed the ability to decolourize the tested dis‐azo and tris‐azo dyes, giving the best performances against the dis‐azo DBU1U1 (600 ppm) dye, which was 100% decolourized after 6 days. Laccases proved to be the main enzymatic activities acting in P. ostreatus decolourization. CONCLUSION: The potential of the fungi P. ostreatus and P. chrysosporium as efficient bio‐systems for decolourization and detoxification of several toxic industrial dyes was demonstrated. The role of laccases in the decolourization of dis‐azo dyes by P. ostreatus was demonstrated for the first time. Copyright © 2008 Society of Chemical Industry     

Combination of biological and chemical processes for the treatment of textile wastewater containing reactive dyes

The treatment of a segregated textile wastewater containing reactive dyes was investigated in two continuous‐flow process trains using ozonation and biological processes. The degree of decolorization and dissolved organic carbon (DOC) removal achieved by ozonation followed by aerobic treatment (two‐stage) was compared with that found when an anaerobic and aerobic pretreatment was added (four‐stage). Although the biological pretreatment reduced color by ～70%, similar amounts of ozone were required in both trains to achieve high degrees of overall removal of color and DOC. In both trains, ozonation increased biodegradability in the following aerobic reactor, however, in order to reach ～80% overall DOC removal, a specific ozone absorption (A*) of ～6 gO₃ gDOC_o^?1 was required and >50% of the DOC was mineralized in the ozone reactor. A comparison of cost estimates based on investment and operating costs for the process alternatives showed that a four‐stage train would reduce costs only if it enabled a decrease in A* to less than 2 gO₃ gDOC_o^?1. Difficulties in comparing treatment processes for segregated vs full‐stream wastewaters are discussed. Copyright © 2003 Society of Chemical Industry     

Anaerobic-aerobic processes for the treatment of textile dyeing wastewater containing three commercial reactive azo dyes: Effect of number of stages and bioreactor type

In this study, the effect of number of stages and bioreactor type on the removal performance of a sequential anaerobic-aerobic process employing activated sludge for the treatment of a simulated textile dyeing wastewater containing three commercial reactive azo dyes was considered. Two stage processes performed better than one stage ones, both in terms of overall organic and color removal, as well as the higher contribution of anaerobic stage to the overall removal performance, thereby making them a more energy efficient option. The employment of a moving bed sequencing batch biofilm reactor, which uses both suspended and attached biomass, for the implementation of the anaerobic stage of the process, was compared with a sequencing batch reactor that only employs suspended biomass. The results showed that, although there was no meaningful difference in biomass concentration between the two bioreactors, the latter reactor had better performance in terms of chemical oxygen demand (COD) removal efficiency and rate and color removal rate. Further exploratory tests revealed a difference between the roles of suspended and attached bacterial populations, with the former yielding better color removal whilst the latter had better COD removal performance. The sequential anaerobic-aerobic process, employing an aerobic membrane bioreactor in the aerobic stage resulted in COD and color removal of 77.1±7.9% and 79.9±1.5%, respectively. The incomplete COD and color removal was attributed to the presence of soluble microbial products in the effluent and the autoxidation of dye reduction metabolites, respectively. Also, aerobic partial mineralization of the dye reduction metabolites, was experimentally observed.     

油田含聚污水过滤工艺因素及臭氧处理效果评价

油田含聚污水随着聚合物驱的应用而黏度增加,水相含油能力强,分离难度大,对处理方式的要求越来越严格。过滤法作为常用方法,其污水处理性能受工艺因素的影响,处理效果不稳定;同时,臭氧作为快速、高效的污水处理方式日益受到关注。本文研究了不同滤料厚度比例、进水流速、滤床压降及污水pH对污水浊度等过滤参数的影响,结果表明核桃壳、石英砂厚度比为9∶13时过滤效果最优,提高进水流速、增加滤床压降和降低污水碱性有利于过滤的进行。探究了臭氧对含油含聚污水的处理效果,结果表明臭氧可通过降解聚合物以显著降低含聚污水黏度,同时污水的浊度和含油量也会显著下降。测定了臭氧降黏的有效消耗量,结果表明5mg臭氧可把500mL的含聚污水黏度从2.6mPa·s降低到1mPa·s以下。最后提出了采用臭氧对过滤污水预处理及处理过滤装置中的板结滤料、提高过滤效率的建议。     

含抗生素废水的微藻处理技术及其进展

抗生素在环境水体的累积是威胁人类健康及生态安全的全球性问题,去除环境中残留抗生素迫在眉睫。本文首先综述了环境中抗生素残留的主要来源及危害。随后,针对微藻处理含抗生素废水的特点,阐述微藻去除抗生素的生物降解、生物累积、生物表面吸附、光合降解和挥发及水解等这5种可能去除机制,比较了这些机制在不同微藻去除抗生素实验研究中的贡献。阐明为提高微藻法去除抗生素的效率,尚需优化藻种的选择和培养条件。最后,讨论了微藻法去除抗生素目前存在的去除不完全、降解产物不明了及缺乏规模化应用等问题,提出可以结合化学、物理和生物方法达到去除要求;通过组学数据等综合分析抗生素降解产物;积累中试数据,为进一步的规模化应用打下基础。     

Studies on usage of acrylamide copolymers for textile effluent treatment

The copolymers of acrylamide–maleic anhydride and acrylamide–diallyl dimethyl ammonium chloride of different ionicities were used for the removal of color, solids, etc., from effluent generated from textile industry. The studies have been carried out to remove color generated in the effluent. To estimate dye content, we prepared standard curve using UV‐vis spectrophotometer at different dye concentration following the Beer Lambert's Law. The copolymers of acrylamide–maleic anhydride and acrylamide–diallyl dimethyl ammonium chloride of known concentration were dosed in the known concentration of the dye. These polymers made flocks by adsorption with dyes and these colored flocks were filtered out. The intensity of the color of water went down on increasing the concentration of the polymers. The color of the textile effluent was removed to the extent of 97% using above mentioned polymers. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

用淀粉黄原酸盐处理含镉废水的研究

主要研究用淀粉黄原酸盐(ISX)处理含镉废水,探讨了淀粉黄原酸盐用量、反应液pH值、反应时间、废水浓度等因素对镉离子去除率的影响。结果表明:当处理20 mL含Cd2+浓度为40 mg/L废水时,pH值为8,ISX用量为0.3 g,处理时间为15 m in,废水中镉的去除率可达97%。     

二氧化钛光催化降解活性染料废水的研究进展

综述了二氧化钛光催化降解活性染料废水的研究成果,对影响二氧化钛光催化降解活性染料废水的各种因素(如催化剂的形态、溶液的pH值、光源与光照强度和溶液中其它物质等)及光催化降解动力学行为进行了讨论,并提出了今后的研究方向。     

Emerging bioremediation technologies for the treatment of textile wastewater containing synthetic dyes: a comprehensive review

The tremendous increase in human population and industrialization has exacerbated the existing problem of water pollution to a great extent. The textile industry is the major cause of this problem due to its significant use of organic synthetic dyes as coloring materials during the dyeing process. The presence of color in wastewater is a major environmental concern, as these dyes are resistant to degradation by physio-chemical treatments. Bioremediation is an attractive method that can completely degrade these dyes while also being cost-effective. This comprehensive review aims to provide a brief insight into bioremediation based on some of the latest emerging wastewater treatment technologies for the removal of synthetic dyes. Starting with the importance of decolorization of synthetic dyes and their environmental impacts, different physio-chemical treatment technologies are analyzed with a special emphasis on their limitations. The bioremediation of textile wastewater with detailed biodegradation mechanisms using different bacterial species (bacteria, fungal, algae, enzyme, and mixed culture) under aerobic and anaerobic conditions is thoroughly discussed. In this article, the major factors affecting the implementation of biological treatment are explained. In addition, the latest emerging treatment technologies, such as nano-bio materials, genetic engineering, phytoremediation, electro-bioremediation (microbial electrochemistry technology, MET), and integrated/hybrid technologies (such as biological processes with physio-chemical processes, electro-coagulation, adsorption, ultra-filtration, membrane, and advanced oxidation) are critically reviewed; their challenges and the future perspectives in textile wastewater treatment are also highlighted. © 2021 Society of Chemical Industry (SCI).     

汽车工业乳化废液超滤出水的生化处理研究

采用序批式活性污泥法(SBR)对经超滤分离后的汽车工业乳化废液进行处理,重点考察了曝气时间对COD去除率的影响。在曝气12h以上,进水COD质量浓度为1500~3000mg/L,污泥负荷不高于1.3kg[COD]/(kg[MLSS]·d)时,COD去除率可以达到74%以上;降低污泥负荷至0.6kg[COD]/(kg[MLSS]·d)以下时,COD去除率可以提高到80%以上。     

利用生物与吸附性物质联合处理焦化废水的研究

对在生化处理的同时加入吸附性物质深度处理焦化厂废水进行了实验研究 ,结果表明 ,吸附性物质的加入可明显提高废水处理效果 ,用焦粉、生物联合处理是深度处理焦化厂废水的一条有效途径。     

对处理含甲酸废水的钯催化剂的研究

采用含吡啶骨架的单体聚会、或缩聚在适当的高分子化合物的主链或在侧链上引入吡啶骨架的高分子化合物在熔融状态下同钯的化合物一起搅拌，形成配合物，再用适当的还原剂处理，得到无定形的金属状的高度分散在高分子化合物载体的钯催化剂，该钯催化剂克服了通常所用的钯催化剂的缺点，它可定量地分解甲酸，且使用寿命较长，可间歇处理甲酸废液，也可连续操作，具有工业实用价值。     

Charged membranes for ultrafiltration treatment of synthetic waste water containing peptone

Continuous ultrafiltration of synthetic waste water containing peptone was carried out by using positively and negatively charged polyacrylonitrile membranes. The filtration experiments were operated in cross-flow mode under 10 kPa of applied pressure. The filtration properties of the charged membranes were compared with those of uncharged polyacrylonitrile ultrafiltration membranes having similar molecular sieve characteristics and membrane structure to the charged ultrafiltration membranes. During the continuous filtration, the filtration rate decreased and the operation pressure increased because of the formation of a peptone gel layer on the membrane surface. It was found that, for the positively charged membrane, the decrease in the filtration rate of the charged membranes was smaller than that of the uncharged membrane. In addition, the positively charged membrane maintained the initial operation pressure during the filtration. The reduction of fouling in the positively charged membrane was discussed by analyzing the gel components on the membrane surface.     

吸附法处理重金属废水的研究进展

综述了吸附法处理重金属废水的研究进展。讨论了天然材料、合成材料、改性材料、生物材料等种类的吸附剂,探讨了各类吸附剂的吸附机理和影响吸附的因素。展望了未来水处理吸附剂的发展方向,廉价的、高效的、无二次污染的吸附剂将会得到大力开发。     

水处理剂发展方向的探讨

本文探讨水处理剂的发展方向，并提出了相应的建议。     

络合萃取法处理高浓度含酚废水的研究

采用我院自行研制的新型高效萃取剂－－HLE处理水杨酸工业废水,一级萃取率＞99．5％,反萃率＞99％,分配比达100以上。     

含酚化工废水处理方法的探讨

探讨了含酚废水的处理方法,重点介绍了处理含低质量浓度（５０～５００ｍｇ／Ｌ）酚的废水的ＰＳＢ活性污泥法,处理含中等质量浓度（１０００ｍｇ／Ｌ左右）酚在废水的生物接触氧化法、处理含高质量浓度（３００００ｍｇ／Ｌ）酚的废水的萃取法。     

利用焙烧天然黄铁矿处理含Cr6+废水的研究

天然黄铁矿对废水中Cr6 的去除能力较低,通过焙烧之后,产生大量的还原性物质,表现出较强的还原性,能有效还原废水中的Cr6 成Cr3 ,沉淀于黄铁矿的表面.考察了焙烧温度、焙烧时间、焙烧黄铁矿的用量以及处理时间对焙烧黄铁矿去除废水Cr6 效果的影响.结果表明,焙烧后,黄铁矿去除Cr6 能力提高到6～7 mg·g-1.