APPLICATIONS OF FLOCCULANT IN BLEACHING AND WASHING OF KAOLIN

The difficulties of washing during the dressing of kaolin ore have been analyzed, the multistep intermittent washing model has been deduced, and effective methods for dealing with the difficulties were put forward. Experimental results show that the bleaching and washing process was enhanced, the washing time was shortened and the consumption of water was reduced by means of adding flocculant.

Study on Comparison between Enzyme Wash and Bleach Wash (Traditional vs. Sustainable Washing Machine) the Physical and Color Fastness to Rubbing Properties of Denim Garments

This study focuses on comparison between Enzyme Wash and Bleach Wash (Traditional vs. Sustainable Washing Machine) the physical and color fastness to rubbing properties of denim garments. For this experiment indigo dyed cotton denim garments (trousers) were chosen which were 98% cotton and 2% spandex and processed by enzyme with the concentration of 2 g/l, and the temperature of 45°C. In another work, enzyme treated denim garments were used for bleach wash with the concentration of 2 g/l, temperature 45°C and those samples have been processed by traditional and sustainable washing machine. After completing process, the sample properties have been compared like rubbing, tearing and tensile properties. After comparing result the color fastness to rubbing of enzyme wash was poor in traditional and sustainable machine and tensile strength, tearing strength properties down in traditional machine but the color fastness to rubbing of bleach wash was good in sustainable machine than traditional machine and a little bit lesser tensile and tearing properties in sustainable process.

Detection of Chlorophenolic Compounds in Bleaching Effluents of Chemical Pulps

Laboratory bleaching effluents from the chlorination and caustic extraction stages of mixed wood kraft pulp processing have been analysed both qualitatively and quantitatively for various chlorophenolics by using GC.A number of chlorinated derivaties of phenols,catechols,guaiacols and syringaldehydes have been detected and their concentrations are estimated.The results are compared with that of different agriculture residue/hardwood pulps,which were reported in literature.The concentrations of various compounds detected have also been compared with their reported 96LC50 values.

ECF Bleaching with Molybdenum Activated Acid Peroxide and its Impact on Eucalyptus Pulp Properties and Effluent Quality

Acid hydrogen peroxide catalyzed with molybdenum (PMo stage) is effective to decrease pulp kappa number and potentially minimize chlorine dioxide demand in subsequent ECF bleaching. This study aimed at developing cost-effective methods for applying PMo as the first stage bleaching for eucalyptus kraft pulp and evaluating their impact on pulp properties and effluent quality in relation to current ECF bleaching techniques. The PMo(EP)DP and A/PMo(EP)DP sequences proved to be most cost-effective for PMo stage application. The pulp properties and effluent quality derived from bleaching with these two sequences were compared with those of the conventional bleaching with the DHT(EP)DP sequence. The PMo(EP)DP sequence produced pulp of refinability and physical properties similar to that of the reference but the A/PMo(EP)DP one resulted in pulp of 20% lower refinability and 10% lower tearing strength. Untreated effluents of the PMo(EP)DP and A/PMo(EP)DP sequences presented similar COD, but lower AOX and color than the DHT(EP)DP effluents. None of the effluents exhibited acute toxicity. The effluents from the PMo(EP)DP sequence showed much lower BOD and BOD/COD ratio than that of the A/PMo(EP)DP one. All effluents were readily treated in bench-scale reactors, and achieved COD removal efficiencies of greater than 70%.

Gas Chromatography Analysis of Resin and Fatty Acids from Laboratory Generated Bleach Plant Effluents

Laboratory generated spent bleached liquor from the chlorination, caustic extraction stage of mixed wood kraft pulp processing has been analyzed both qualitatively and quantitatively for various resin & fatty acids by using GC. A number of resin acids, saturated and unsaturated fatty acids, chloro fatty and resin acid have been detected and their concentrations are estimated. The results are compared with results on different agriculture residue/hardwood pulps, which were reported earlier. The concentrations of various compounds detected have also been compared with their reported LC50 values.

An Experimental Investigation of Different Washing Processes on Various Properties of Stretch Denim Fabric

This research work was designed to explore the effect of different washing processes (enzyme wash, enzyme stone wash, enzyme stone wash with bleaching, heavy enzyme stone wash with bleaching) on various properties of stretch denim fabric. Different properties like tensile strength, tear strength, dimensional stability to washing, color fastness to washing, color fastness to water, color fastness to perspiration, color fastness to light, color fastness to rubbing, changes in fabric weight were investigated in context with different washing processes for stretch denim fabric. All tests were carried out according to the ISO (International Organization for Standardization). Enzyme washed fabric illustrated better performance regarding tear strength, tensile strength and dimensional stability;but showed moderate performance in different color fastness properties. But the color fastness to rubbing of heavy enzyme stone wash was excellent. No significant change was observed regarding the grade of color change and color staining for color fastness to wash, color fastness to perspiration and color fastness to light with respect to different types of washing processes like enzyme wash, enzyme stone wash, enzyme stone wash with bleaching and heavy enzyme stone wash with bleaching. The grade for dry rubbing and wet rubbing was comparatively better for enzyme wash rather than other washing processes. The GSM (gram per square meter) of stretch denim fabric also increased accordingly after different kinds of washing process rather than untreated stretch denim fabric. The dimensional stability of stretch denim fabric also altered after going through different washing process. The highest shrinkage was occurred in weft direction for heavy enzyme stone wash with bleaching.

STUDY ON TREATING ALKALI EXTRACTION-STAGE EFFLUENT FOR COLOR REMOVAL BY MICRO-ELECTROLYSIS METHOD

The micro-electrolysis technology was applied in the decolorizing treatment of bleaching E-stage effluent and the influencing factors were discussed in this paper. The initial pH and the retention time were main factors influencing the color removal rate, in addition, adding air and enough pH for neutralization were necessary for the treatment. The test showed that the decolorizing result was efficient by micro-electrolysis treatment when adding air, initial pH was 3, 20 minutes of reaction time, the final pH 10 for neutralization. The color removal rate was up to 90%. The chance of ultraviolet absorption spectrum also demonstrated the mechanism of color removal in the wastewater treatment.

2022中国国际纺织机械展览会暨ITMA亚洲展览会针织物印染前处理机械述评

介绍了2022中国国际纺织机械展览会暨ITMA亚洲展览会展出的针织染整前处理设备,包括设备的外观结构图、应用工艺流程图和的应用技术特点等。并对多家公司展出的设备进行述评,指出:针织物开幅平幅运行的连续化练漂机、除油精练机和水洗机的制造技术及其应用技术虽已趋于成熟,但当下行业中实际应用的厂家还是很少;绳状松式运行的连续化练漂机、水洗机呈现快速发展的态势,具有适应织物范围广和应用工艺范围广以及松式运行方式等优点,可弥补开幅平幅练漂机和水洗机的不足;圆筒状针织物无须剖幅就能松式运行的连续化练漂机,有许多突出优点,也应予以关注;烧毛、丝光是保证棉型针织物布面光洁度和平整度以及尺寸稳定性的重要工序,应成为针织物染整技术的重点内容。

Shewanella sp.JN01对水体系不同络合态Cu的去除效果及机理

土壤淋洗废液处理难点在于废水中含有高浓度的稳定重金属络合物.本研究分离了一株硫酸盐还原菌(Shewanella sp.JN01),探讨了其对模拟淋洗废液中不同络合态Cu(Cu-乙二胺四乙酸(Cu-EDTA)、Cu-谷氨酸N,N-二乙酸(Cu-GLDA)、Cu-柠檬酸(Cu-CA)和Cu-混合淋洗剂(Cu-MC))的去除效果及机理.结果表明,活菌体和死菌体对不同络合态Cu的去除率分别大于80%和小于8%.显然,死菌体细胞表面吸附作用对络合态Cu去除效率的贡献十分有限.因此,Shewanella sp.JN01去除络合态Cu的主要机制是先破络,再形成CuS沉淀.Shewanella sp.JN01对不同络合态Cu的去除率为Cu-CA>Cu-MC>Cu-GLDA>Cu-EDTA,这一变化趋势与它们的稳定性常数和毒性的变化趋势相反,结果进一步证实了破络是微生物去除络合态重金属的限制性步骤.Shewanella sp.JN01能够有效去除土壤淋洗废液中重金属络合物,在淋洗废液再生利用方面具有潜在应用前景.

“三线一单”生态环境分区管控在新塘镇牛仔洗漂行业转型升级中的应用

随着新塘镇牛仔洗漂产业的快速发展,其与周边居民的环境问题不断尖锐。介绍了广州市增城区为解决多年投诉顽疾,积极探索生态环境分区管控手段,先行先试在工业园区尺度上应用生态环境分区管控技术,在镇域范围开展环境控制性规划探索,在国家统一指导下开展全区“三线一单”生态环境分区管控工作,对新塘镇牛仔洗漂行业巩固升级改造成果和后续发展提出要求等工作进展,并得出结论,通过生态环境分区管控避免了对牛仔服装行业传统“一刀切”式的环境管理,实现了差别化分区管理,促使传统污染型企业转变成为先进、绿色的现代化企业。

新型有机还原剂用于钛白生产工艺的可行性研究

硫酸法钛白粉生产过程中,白度是关键指标之一。对高效有机还原剂还原能力进行考察,并利用此还原剂进行了水解偏钛酸的洗涤,同时与三价钛进行比对。结果表明,新型有机还原剂能够在硫酸法钛白粉生产过程中对一洗、二洗除铁有很大的帮助,能够有效抑制亚铁被氧化,从而使洗涤效率极大提高。而还原剂更能够适应洗涤过程中温度、酸度的变化,使其保持高效的还原能力,能够直接应用在硫酸法钛白粉工艺的漂白工序中,实验结果良好。

Fenton法深度处理制浆中段废水的工程应用

介绍了采用Fenton法深度处理制浆中段废水的工程实例,考察了各处理单元的最佳工艺参数及连续运行时的处理效果。工程运行结果表明,该方法工艺简单、占地面积小、运行费用低、运行稳定且废水处理效果好。在3个月稳定运行期间,出水CODC r<100 mg/L,色度<30倍,符合《制浆造纸工业水污染物排放标准》(GB3544—2008),达到了节能减排,保护环境的目的。

制浆中段废水污染特征及脱色处理方法

研究了木浆和竹浆中段废水的污染特征以及脱色方法。研究结果表明,制浆中段废水的生化性差,其分子质量较大的有机物是废水色度的主要来源,并且随着废水pH值的升高其色度也加深,混凝法是简单有效的脱色处理方法。

AOX漂白废水对黑鲷鱼卵及仔鱼的毒性效应

用含AOX的造纸漂白废水对人工养殖的黑鲷鱼卵和早期仔鱼进行了毒性实验．结果表明：对于AOX漂白废水的毒性，黑鲷鱼卵胚胎阶段比早期仔鱼阶段更为敏感．高浓度的AOX漂白废水对鱼卵孵化产生一定的抑制作用，对仔鱼产生尾部畸形和致死现象，鱼卵孵化的EC50和95％置信区间分别为0．018和0～0．087mL／mL；仔鱼72h LC50和96h LC50分别为0．557和0．774mL／mL，72h的LOEC和NOEC分别为0．032和0．001mL／mL，96h的LOEC和NOEC分别为0．003和0．001mL／mL．表明仔鱼对AOX漂白废水的毒性敏感性随着时间的推移而逐渐减弱．

PVA-H_3BO_3包埋白腐菌处理苇浆漂白废水的研究

用PVA-H3BO3包埋白腐菌时，添加0．5％海藻酸钠可以有效地克服PVA附聚性强、成球性难的操作困难。在较适宜的制备条件（8％PVA、0．5％海藻酸钠、3％细胞浓度）下制备的固定化白腐菌间歇式连续处理E段废水1个月，处理效果较稳定，脱色率保持80％左右，TOCI去除率50％～58％，PVA小球没有破碎。扫描电镜观察到PVA具有外密内疏的多孔结构。

生物流化床-化学絮凝法处理纸浆漂白废水

使用内循环三相生物流化床处理纸浆含氯漂白废水,经过40d左右的驯化,COD、BOD去除率达到70%以上,色度去除达到70%左右,AOX去除率达到60%左右,后续絮凝处理采用聚铁铝(PFAC)作为絮凝剂,聚丙烯酰胺(PAM)作为助凝剂,出水COD为80mg/L左右,BOD为20mg/L左右,AOX<1mg/L,色度为120C.U。

铁屑微电解-混凝深度处理麦草浆中段废水

采用铁屑微电解-混凝组合工艺对麦草制浆造纸中段废水进行深度处理。实验表明,曝气条件下,调节废水的初始pH值5.2,废水与铁屑体积比为3.0,进行微电解反应20min,然后调节pH值为9.3进行混凝沉淀,出水澄清透明,CODCr和色度去除率分别可达68.4%和98.7%;紫外光谱分析表明,出水的吸收峰范围和强度大大减小,共轭双键、芳环等基团大量减少,废水中的特征污染物得到有效去除。

Fe^(3+)存在下制浆中段废水好氧活性污泥的驯化

研究了Fe3+存在下处理制浆中段废水的好氧活性污泥的驯化过程。首先通过Fe3+对微生物生长曲线的影响确定Fe3+最佳用量为30 mg/L;然后在Fe3+用量为30 mg/L下,采用制浆中段废水对好氧活性污泥进行驯化,并设置不加Fe3+的空白组对照。结果表明,整个驯化过程中,加Fe3+组CODCr去除率和污染物去除率(以UV-254减少率表示)均高于空白组;驯化结束后,加Fe3+组和空白组CODCr去除率分别达78.2%和76.0%,污染物去除率分别为50.0%和37.7%。通过对脱氢酶活性的分析表明,加Fe3+组活性高于空白组。

制浆造纸中段废水深度处理

采用混凝水解曝气生物滤池工艺对制浆造纸中段废水进行了深度处理。结果表明,该工艺可有效去除中段废水两级生化处理后出水的COD和色度,深度处理出水平均CODCr和色度分别为60.2mg/L和55倍,低于国家排放标准。该系统具有流程简单、处理效率高、运行稳定可靠等优点。

吸附法固定白腐菌处理苇浆漂白废水的研究

将白腐菌吸附固定在煤渣表面，连续处理苇浆漂白废水，操作简单，运行费用低，处理效果稳定；用五灰水进一步进行混凝处理后，出水水质清，基本达到排放标准。