“氧化·脱色·絮凝”协同法处理含吡啶酮废水

根据染料中间体吡啶-2-酮生产废水的特点,提出了利用“氧化、脱色和絮凝”三位一体的物化方法处理这种废水;探究了搅拌速度、絮凝反应时间、pH值、药剂用量、废水浓度和温度对COD去除率和脱色率的影响,得出了最佳工艺条件.研究结果表明,在常温下,两性聚丙烯酰胺NDPAM用量35 mg/L,氧化交联剂PDO用量0.55 mL/L,pH=5.7,搅拌速度80 r/m in,絮凝时间为15 m in和静止时间为30 m in的条件下,COD的去除率和脱色率均达到98%,处理后的废水达到了可生化的指标范围.并对处理成本和絮凝动力学机理进行了探讨.     

复合型高效絮凝脱色剂处理印染废水的研究

选用自制的双氰胺甲醛作为絮凝脱色剂处理高浓度印染废水,并与硫酸铝、三氯化铝作了对比实验。考察了投加量、pH值、反应温度等因素对絮凝效果的影响。实验结果表明在用量较少并且其它操作条件相同的情况下,双氰胺甲醛制备的脱色絮凝剂具有很好的絮凝脱色效果及COD_(Cr)去除率。在最佳的操作条件下(投加量120 mg/L,pH=7,反应温度25℃),此脱色絮凝剂对分散、酸性、活性印染废水的COD_(Cr)去除率分别为79.1%、78.5%、79.0%,对分散、酸性、活性印染废水的脱色率分别为94.0%、97.1%、72.9%,减轻了后续处理难度。在与无机絮凝剂的对比试验中,在相同的条件下有机絮凝剂的处理效果总体比无机絮凝剂的处理效果好。     

分散液液微萃取-微量分光光度法测定再造烟叶废水中烟碱

基于2,6-二氯靛酚与烟碱的荷移反应生成红色络合物,以氯仿为萃取剂,乙腈为分散剂,建立了分散液液微萃取(DLLME)-微量分光光度法测定烟碱含量的方法,用于再造烟叶废水中烟碱的测定。研究了酸度、萃取剂种类及用量、分散剂种类及用量等条件对测定的影响。在优化条件下,此方法的线性范围为1~100 mg/L(R2=0.9996),检出限为0.42 mg/L。相对标准偏差为1.3%~3.5%(n=6),加标回收率为95.9%~102.1%。该方法可满足再造烟叶废水中烟碱快速测定的要求。     

红霉素生产废水的树脂吸附法处理研究

采用XDA-1大孔吸附树脂对琥乙红霉素和红霉素碱两种生产废水分别进行动态吸附处理,研究影响吸附的一些因素.结果显示,在室温、原废水pH和较低流速条件下,经处理后废水的COD降低72%～88%;经丙酮解吸后再从解吸液蒸馏回收99%的醋酸丁酯,从琥乙红霉素废水中还可回收大约0.4kg/m3的红霉素粗品.     

近红外光谱结合偏最小二乘判别分析区分造纸法再造烟叶产品

本文采集162个造纸法再造烟叶产品的近红外光谱,结合偏最小二乘判别分析(PLS-DA)建立了再造烟叶产品的分类模型,实现了不同牌号再造烟叶产品的快速分类,并对45个预测集样品的牌号进行了分类预测。所建模型对校正集和预测集的预测正确率分别为100.0%和95.5%,与主成分分析(PCA)相比,PLS-DA对不同牌号再造烟叶产品的分类具有更好的效果。该模型为不同牌号再造烟叶产品分类提供了一种新的快速鉴别分析的方法,同时可初步监测再造烟叶产品的质量稳定性。     

利用造纸污泥制备木素基阳离子絮凝剂及其性能的研究

以造纸污泥中提取的木质素为原料,合成了木素基阳离子絮凝剂。研究了催化剂种类、反应物配料比、反应温度、反应时间等对合成产物脱色性能的影响,确定了较佳合成工艺条件为:引发剂K2S2O8用量为木质素磺酸钠质量的0.7%,活化时间1.5 min,木质素磺酸钠与单体质量比为1∶1.5,反应温度为70℃,反应时间1.5 h,采用红外光谱对产物结构进行了表征。产物对几种模拟染料废水具有良好的脱色性能,在酸性(pH1～2)条件下,脱色率均达84.4%以上。通过比较木质素与接枝产物的絮凝效果以及絮体的微观形貌,对其絮凝机理进行了初步探讨。     

优势菌固定化细胞对偶氮染料脱色的研究

利用紫外线诱变技术选育出高活力偶氮染料活性艳红X-3B脱色菌UVM7-9，以海藻酸钠为载体，采用包埋法固定UVM7-9细菌细胞用于处理含X-3B模拟废水。以固定化细胞对X-3B的脱色率和脱色寿命为试验指标，确定了最佳脱色条件，并与游离细胞对X-3B的脱色效果进行比较。结果表明，固定化细胞适应环境条件的范围更宽，脱色能力强，在30-35℃环境温度条件下，控制溶液pH为8，24h内对浓度为50mg／L的X-3B模拟废水的脱色率达93．8％。     

再造烟叶循环白水中细菌检测方法的确立

以再造烟叶生产过程中循环白水为研究对象,通过对几种常用细菌检测方法的分析和比较,结果发现,吖啶橙染色直接计数法的检测结果,在表征循环白水中的细菌总数时效果最好,适合用于白水系统中细菌的测定.对吖啶橙染色直接计数检测法进行了合理的改进,确立了适用于再造烟叶循环白水中细菌总数的检测方法.     

铁炭微电解-亚铁还原氧化法处理花菁废水的研究

研究了微电解-亚铁还原氧化法在处理花菁废水上的应用,结果显示,经过处理,废水色度的去除率>97%,化学需氧量(COD)的去除率>90%.研究了影响处理效果的因素,对于废水中有机物的去除、脱色以及废水可生化性的提高进行了探讨,并通过紫外-可见光谱和色质联用(GC/MS)对处理前后的废水组分进行了分析.     

复合型絮凝剂处理油墨废水的研究

以3-氯2-羟丙基三甲基氯化铵(CHPTMAC)、玉米淀粉、AlCl_3、Al_2(SO_4)_3、PAC、FeSO_4、FeCl_3等无机絮凝剂为原料制备出一种有机无机复合型絮凝剂(PMSF),并用于福建某油墨生产企业,系统考察了其对油墨废水进行处理时的最优条件。试验发现,PMSF对油墨废水有很强的絮凝和脱色效果,废水的COD去除率可达到86.8%,色度去除率可达到94.6%。对比试验结果表明,PMSF处理油墨废水的絮凝综合性能明显优于季铵化淀粉絮凝剂(MSF)。     

Industrial indigo dyeing wastewater purification: Effective COD removal with peroxi-AC electrocoagulation system

Direct current (DC) electrocoagulation has obvious decolorization effect on indigo dyeing wastewater produced in actual production, while the removal rate of chemical oxygen demand (COD) was less than 40%, accompanied by serious electrode corrosion and high energy consumption. In order to enhance the COD removal rate, reduce the electrode loss and power consumption, a peroxi-alternating current (AC) electrocoagulation (EC) system was constructed. With COD as the main evaluation index, the effects of power type, electrode combination and process parameters on COD removal rate and decolorization rate were focused on and explored, as well as revealing the degradation mechanism of COD. The results showed that AC electrocoagulation enhanced the floc adsorption capacity by improving the floc structure, and the COD removal rate after treatment was 51.19%. The coupled system of peroxi-AC electrocoagulation further removed sulfite and residual dyes in the wastewater, and the COD removal and decolorization rate of the treated wastewater reached 78.09% and 98.47%, respectively. In addition, the specific energy consumption analysis of COD removal showed that the coupled system was far less energetic than the DC electrocoagulation process, with only 30% of its energy consumption. The uniform corrosion of the electrode under the action of AC weakened the passivation, which reduced the electrode loss and power consumption by 22.73% and 43.75%, respectively. Results from the present work indicated that the peroxi-AC EC system could be an effective method for reducing the concentration of COD in indigo dyeing wastewater.     

Screening thermotolerant white-rot fungi for decolorization of wastewaters

To select a thermotolerant fungal strain for decolorization of wastewaters, ligninolytic enzyme production (lignin peroxidase, manganese peroxidase [MnP], and laccase), decolorization, and removal of total phenol and chemical oxygen demand (COD) were detected. Thirty-eight fungal strains were studied for enzyme production at 35 and 43°C on modified Kirk agar medium including 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and MnCl₂. Thirteen strains grew on manganese-containing agar and provided green color on ABTS-containing agar plates under culture at 43°C. Decolorization of wastewater from alcohol distillery (WAD) by these strains was compared under static culture at 43°C, and Pycnoporus coccineus FPF 97091303 showed the highest potential. Thereafter, immobilized mycelia were compared with free mycelia for WAD decolorization under culture conditions of 43°C and 100 rpm. The immobilized mycelia on polyurethane foam enhanced the ligninolytic enzyme production as well as total phenol and color removal. At about the same COD removal, MnP and laccase produced by immobilized mycelia were 2 and 19 times higher than by free mycelia; the simultaneous total phenol and color removal were 3.1 and 1.5 times higher than the latter. Moreover, decolorization of synthesis dye wastewater was carried out at 43°C and 100 rpm. More than 80% of 300 mg/L of reactive blue-5 was decolorized by the immobilized mycelia within 1 to 2 d for four cycles.     

Efficient photocatalytic treatment of sugar mill wastewater with 2%Ag3PO4/Fe/GTiP nanocomposite

The large amount of colored substances exist in the sugar mills wastewater that give higher organic load to the effluent. Therefore, a novel study of sugar mill wastewater treatment was carried out under photocatalysis by using a nanocomposite of silver phosphate-iron-graphene oxide-titanium phosphate (Ag₃PO₄/Fe/GTiP). The catalyst was prepared by simple chemical process with 2% content of Ag₃PO₄ to Fe/GTiP. The light, catalyst dosage, pH, and scavenger impacts on the decolorization and chemical oxygen demand (COD) removal from the sugar mill wastewater were observed. The highest decolorization and COD removal of 85.02% and 80.3% was achieved under pH-1 by using 50 W visible halogen light at catalyst dosage of 100 mg/75 ml in 200 min. The excellent recycled results were observed up to four cycles. The obtained results proves that this catalyst has high photocatalytic efficiency to treat the sugar mill wastewater.     

Current Technologies for Biological Treatment of Textile Wastewater–A Review

The release of colored wastewater represents a serious environmental problem and public health concern. Color removal from textile wastewater has become a big challenge over the last decades, and up to now, there is no single and economically attractive treatment method that can effectively decolorize the wastewater. Effluents from textile manufacturing, dyeing, and finishing processes contain high concentrations of biologically difficult-to-degrade or even inert auxiliaries, chemicals like acids, waxes, fats, salts, binders, thickeners, urea, surfactants, reducing agents, etc. The various chemicals such as biocides and stain repellents used for brightening, sequestering, anticreasing, sizing, softening, and wetting of the yarn or fabric are also present in wastewater. Therefore, the textile wastewater needs environmental friendly, effective treatment process. This paper provides a critical review on the current technology available for decolorization and degradation of textile wastewater and also suggests effective and economically attractive alternatives.     

The effect of recycling flux on the performance and microbial community composition of a biofilm hydrolytic-aerobic recycling process treating anthraquinone reactive dyes

Synthetic dyes are extensively used and rarely degraded. Microbial decomposition is a cost-effective alternative to chemical and physical degradation processes. In this study, the decomposition of simulated anthraquinone reactive dye (Reactive Blue 19; RB19) at a concentration of 400-mg/L in wastewater by a biofilm hydrolytic-aerobic recycling system was investigated over a range of recycling fluxes. The 16S rDNA-based fingerprint technique was also used to investigate the microbial community composition. Results indicated that the recycling flux was a key factor that influenced RB19 degradation. The RB19 and COD removal efficiency could reach values as high as 82.1% and 95.4%, respectively, with a recycling flux of 10 mL/min. Molecular analysis indicated that some strains were similar to Aeromonadales, Tolumonas, and some uncultured clones were assumed to be potential decolorization bacteria. However, the microbial community composition in the reactors remained relatively stable at different recycling fluxes. This study provided insights on the decolorization capability and the population dynamics during the decolorization process of anthraquinone dye wastewater.     

SnO2的制备及催化臭氧氧化活性

采用沉淀法制备了SnO2催化剂,以SnO2催化臭氧氧化降解糖蜜酒精废水脱色为探针反应,对催化剂的活性进行了评价.采用X射线衍射、红外光谱及热分析(TG-DSC)等技术对催化剂进行表征,研究了沉淀剂及焙烧温度等制备参数对SnO2催化臭氧氧化活性的影响.结果表明,SnO2催化剂对臭氧氧化降解糖蜜酒精废水脱色具有较高的催化活性,反应60 min后,糖蜜酒精废水的脱色率从单独臭氧氧化的43.04%提高到60.24%.沉淀剂对SnO2催化剂的活性影响很大,其中以氨水为沉淀剂制备的SnO2催化剂去羟基化反应程度高,所制得的催化剂活性最大.催化剂适宜的焙烧温度为723 K.SnO2吸附吡啶的红外光谱表明,催化剂表面存在L酸中心.臭氧在SnO2表面吸附的红外光谱表明,通过臭氧的末端氧原子与表面羟基及L酸中心成键,生成的活性氧可氧化降解糖蜜酒精废水.     

Preparation for Magnetic Nanoparticles Fe3O4 and Fe3O4@SiO2 and Heterogeneous Fenton Catalytic Degradation of Methylene Blue

Dyestuff textile wastewater treatment has become a research hotspot due to its high chroma, poor biodegradability, and low toxicity characteristics. In this paper, we have synthesized magnetic Fe₃O₄ and core‐shell Fe₃O₄@SiO₂ materials by hydrothermal methods. These materials were characterized by XRD, TEM, N₂ adsorption‐desorption and so on. These materials’ heterogeneous Fenton has been applied to dye wastewater treatment. Methylene blue was used as a typical target of dye wastewater. Decolorization ratios of methylene blue were determined by different nanostructure composites catalysts. A serious of results of study showed that decolorization ratios of magnetic nanoparticles and core‐shell composites arrived at above 90 % under the weakly acidic or neutral conditions and room temperature. When these catalysts were reused, the results show that Fe₃O₄@SiO₂ materials were possessed with good cycle performance.     

Textile Dye Biodecolorization by Manganese Peroxidase: A Review

Wastewater emissions from textile factories cause serious environmental problems. Manganese peroxidase (MnP) is an oxidoreductase with ligninolytic activity and is a promising biocatalyst for the biodegradation of hazardous environmental contaminants, and especially for dye wastewater decolorization. This article first summarizes the origin, crystal structure, and catalytic cycle of MnP, and then reviews the recent literature on its application to dye wastewater decolorization. In addition, the application of new technologies such as enzyme immobilization and genetic engineering that could improve the stability, durability, adaptability, and operating costs of the enzyme are highlighted. Finally, we discuss and propose future strategies to improve the performance of MnP-assisted dye decolorization in industrial applications.     

A cost-effective anionic flocculant prepared by grafting carboxymethyl cellulose and lignosulfonate with acrylamide

How to efficiently utilize most abundant biomass of cellulose, lignin and their derivatives has become an emerging challenge as the anticipative oil depletion. In this paper, the ternary anionic copolymer of carboxymethyl cellulose-acrylamide-lignosulfonate (CAL) was successfully prepared by hydrothermal polymerization. Based on the flocculation characteristics of cationic methylene blue, the optimal polymerization process was confirmed as the raw material ratio of 1:1:1, initiator dosage of 0.9 wt %, the reaction time was 5 h and the reaction temperature was 55 °C. The results showed that the decolorization ratio was 87.5% at the CAL dosage of 600 mg/L for the 500 mg/L methylene blue simulated wastewater. The CAL achieved fast flocculation kinetics and super color removal ratios in the wide ranges of environmental pH, temperature and salt concentration. The flocculation mechanism is single charge neutralization. Moreover, the estimated treatment cost of CAL is 68.3% lower than that of commercial anionic PAM. The prepared anionic CAL flocculant has the characteristics of environmental safety, excellent flocculation performance and cost-effectiveness, which shows great potential in the field of dye wastewater treatment, and also provides a feasible way for the effective utilization of biomass resources.