用表面活性剂含量判定洗涤终点的探讨

利用直接两相滴定方法对洗衣剂洗涤衣物各个过程的溶液进行阴离子表面活性剂含量的测定,确定了漂洗终点时,溶液中阴离子表面活性剂含量的范围在2 mg/kg以下。同时,考察了直接两相滴定方法测定相当于实际洗涤、漂洗各溶液阴离子表面活性剂含量的十二烷基苯磺酸(LAS)溶液的重复性和精密度,得出它们相对标准偏差(RSD)分别为:0.62%(500 mg/kg),4.10%(15 mg/kg),4.88%(5 mg/kg)和11.28%(2 mg/kg)。     

Radiotracer detergency testing in a horizontal-axis washing machine

Proposed regulations by the U.S. Department of Energy have spurred development of energy-efficient washing machines that utilize less water and operate with lower energy requirements than conventional machines. As a result, major changes in washing machine design are required. Among expected changes are increased use of a horizontal-axis wash tub, an increase in fabric-to-wash liquor ratio, greater surfactant concentration in the wash water, and reduced average washing temperatures. As a result, surfactants used in future detergent formulations will be required to clean effectively in this new regime while producing minimal foam. Detergency test methods utilizing radiotracer techniques have been developed to study the detergency process in energy-efficient washing machines. Detergency and redeposition of radiolabeled oily soils can be determined in a full-size horizontal-axis washing machine through scintillation counting of wash and rinse water samples. Measurements can be made after each wash process step and combined to determine total cycle detergency. This is a distinct advantage over conventional reflectance detergency methods where only total detergency at the end of the entire washing and rinsing process can be conveniently measured. Also, in contrast to indirect reflectance methods, measurements of absolute soil removal are obtained with the radiotracer method. In this study, soil redeposition was determined by measuring residual radioactivity on fabric swatches and then performing a material balance on the oily soil.     

Pretreatment with fine bubbles for effective zinc ion precipitation and removal from zinc electroplating wastewater

Heavy metals such as zinc are widely used in plating plants for the processing of material surfaces; therefore, an adequate wastewater treatment is required afterwards to comply with wastewater regulations. However, the presence of chemicals such as degreasing agents in the wastewater generated from the plating process inhibits the formation of hydroxides, thereby making treatment of wastewater and compliance with the stipulated regulations difficult. Herein, the effects of fine bubbles on oil cleaning and wastewater treatment were investigated for developing an alternative cleaning technology to degreasing agents. The concentration of fine bubbles significantly affected the oil cleaning. The fine bubbles demonstrated remarkable cleaning of highly viscous oil, which was difficult to remove using pure water. The high cleaning effect of fine bubbles on oil was achieved because of the hydrophobic interaction of the bubbles. Furthermore, a decrease in cleaning effect was observed for samples with uneven shapes, which was attributed to the difficulty in penetration of fine bubbles in materials with irregularities. Furthermore, fine bubble cleaning exhibited better efficiency for wastewater treatment than degreaser cleaning. Therefore, fine bubble cleaning is speculated to be an excellent cleaning technology with high oil cleaning effectiveness and improved wastewater treatability.     

4种阴离子表面活性剂易漂洗性能的比较研究

采用实验室建立的同时测定模拟漂洗硬水条件下泡沫衰减性和织物上表面活性剂的初始/残留吸附量的方法,对家居织物洗涤剂中常用的4种典型的阴离子表面活性剂的易漂洗性能进行了比较研究,并考察了易漂洗性能与表面活性剂的钙离子稳定性之间的关系。实验结果表明,表面活性剂的钙离子稳定性与硬水漂洗液的泡沫性正相关,而与表面活性剂在织物上的初始/残留吸附量负相关。具有适中钙离子稳定性的改性羧酸盐(N-月桂酰基肌氨酸钠)具有最佳易漂洗性,磺酸盐(十二烷基苯磺酸钠)次之,而钙离子稳定性极低的皂类(月桂酸钠)或钙离子稳定性极高的阴-非离子型硫酸酯盐(十二烷基聚氧乙烯醚硫酸钠)均不属于易漂洗表面活性剂。这一研究结果对易漂洗阴离子表面活性剂的分子结构设计以及节水型洗涤剂的研发具有理论指导意义和应用价值。     

Biosurfactants as Alternatives to Chemosynthetic Surfactants in Controlling Bubble Behavior in the Flotation Process

To examine the usage of biosurfactants as potential alternatives to chemosynthetic surfactants in controlling bubble behavior in the flotation process, a high-speed photographic method was employed to measure the motion of single bubbles and the size distribution of bubbles in the presence of biosurfactants in a laboratory scale flotation column. Deionized water, rhamnolipid, tea saponin and t-C8phenolethoxylateEO9 were used for making various surfactant solutions. Bubble trajectory, dimensions, velocity and size distribution were then determined from the recorded frames using the image analysis software. The results show that similar to chemosynthetic surfactants, the addition of biosurfactants has significant effects on bubble motion and size distribution. The addition of a small amount of tea saponin can significantly dampen bubble deformation, slow down terminal velocity, stabilize bubble trajectory, reduce bubble size and increase the specific surface area of bubbles due to the Marangoni effect. In addition, the biosurfactant effect on bubble behavior has been also found to depend on their type and concentration. The effect of tea saponin, fairly close to C8phenolethoxylateEO9, is stronger than rhamnolipid. The findings in the present study suggest that such biosurfactant as tea saponin may be good substitutes of chemosynthetic surfactants to control bubble behavior in flotation operation.     

SEBS高黏度溶液气液鼓泡塔的流体力学研究

针对SBS加氢反应器开发与设计,以SEBS-1650己烷溶液为液相,采用差压法和床层塌落法研究了气液鼓泡塔中高黏度溶液的流体力学行为,考察了黏度对低表面张力溶液的气含率、大小气泡气含率、大小气泡上升速度和比表面积等因素的影响。结果表明,随黏度增加,大气泡增多,气含率明显降低,塔内流型处于湍流区;由床层塌落曲线确定鼓泡塔内存在三种类型的气泡：大气泡、小气泡及细小气泡,随黏度增加,小气泡与细小气泡逐渐减少;黏度对大小气泡的上升速度略有影响,比表面积随黏度增加而明显降低。根据实验结果给出了大小气泡气含率与平均气含率的计算公式。     

The effect of different types of micro‐bubbles on the performance of the coagulation flotation process for coke waste‐water

BACKGROUND: Comparison experiments were carried out with three kinds of micro‐bubbles on the coagulation flotation process treatment of coke waste‐water under optimum coagulation conditions obtained from zeta potential measurement. RESULTS: Micro‐bubble flotation with ozone showed the best performance. The ozone micro‐bubbles exhibited high absolute zeta potential values, creating repulsion forces thus avoiding the coalescence of bubbles as well as creating attractive interaction between bubbles and particles in the waste‐water. Moreover, the fluorescence intensity of three micro‐bubble samples showed that the ozone micro‐bubble system produced the most hydroxyl radicals, which contributed to the degradation of organic material in the coke waste‐water. Compared with either air micro‐bubble flotation and oxygen micro‐bubble flotation processes, pyridine removal efficiency of the ozone micro‐bubble flotation process was, respectively, 4.5 and 1.7 times higher, and benzene removal efficiency 3.6 and 1.5 times higher. Finally, drainage models and oxygen diffusion models of the three kinds of micro‐bubble water samples verified the long persistence of the three kinds of micro‐bubbles in the water. CONCLUSION: The application of ozone micro‐bubble technology in coagulation processes may provide an efficient and cost‐effective approach to the treatment of waste‐water containing refractory organic compounds. Copyright © 2011 Society of Chemical Industry     

Microemulsion Formation and Detergency with Oily Soil: IV. Effect of Rinse Cycle Design

The objective of this work was to apply a microemulsion-based formulation for the removal of motor oil in laundry detergency at low salinity. To produce the desired phase behavior, three surfactants were used: alkyl diphenyl oxide disulfonate (ADPODS), sodium dioctyl sulfosuccinate (AOT) and sorbitan monooleate (Span 80). The mixed surfactant system of 1.5% ADPODS, 5% AOT and 5% Span 80 (13 parts ADPODS, 43.5 parts AOT, and 43.5 parts Span 80 of the total actives) was found to form a middle phase microemulsion (Type III) at a relatively low salinity of 2.83% NaCl. When this formulation was diluted, detergency performance increased with increasing total surfactant concentration and leveled off above about 0.1% total actives on the three types of fabrics studied (pure cotton, 65/35 polyester/cotton blend, and pure polyester). Detergency was found to improve with increasing hydrophilicity of the fabric with cotton being cleanest after washing and polyester the most difficult to clean. To achieve a specified oil removal, less rinse water can be used if a higher number of lower-volume rinses are employed. An interesting characteristic of microemulsion-based formulations is that a substantial fraction of oil removal occurs during the rinse cycle. In this work, this removal is shown to be due to the low oil/water interfacial tension during initial rinsing and is therefore strongly correlated to residual surfactant concentration in the rinse steps. As a result, the number of rinses and the volume of water per rinse can profoundly affect detergency in these systems.

洗衣机漂洗效率及影响因素的研究

对洗衣机漂洗效率的检测方法进行了实验研究。在传统的碱性残留检测法基础上,运用两相滴定法测定残留漂洗液中活性物含量,计算了活性物漂洗率。同等漂洗条件下,活性物残留量高于碱性物质残留量,第1、2次漂洗差异明显,第3次漂洗后基本一致。运用两种检测方法分别测定漂洗比、水温、含水率、漂洗时间对漂洗效率的影响,提出了漂洗程序的改进方案。     

Weichspülmittel

Soft Washing Agents The degree of softening achieved at the surface of terry cloth by the action of a washing agent depends upon the structure of the fabric and its molecular weight as well as upon the hardness of water. This is owing to the adsorption of the washing agent on the fibre. Highest degree of softening is attained if at the last stage of washing a cation-active surfactant is added to the rinsing water. However, a quaternary ammonium compound which is employed currently, makes the fabric rather strongly water repelling. It was found out that certain sulfonium compounds impart considerable softness to the fabric without rendering them excessively water repellent.     

Stability Modeling of Water-Based Surfactant Covered Micro-bubble Fluids

Currently, due to the decrease in easy access to crude oil reservoirs, oil and gas industries have focused on production from heavy oil and depleted reservoirs. In recent years, micro‐bubble fluids with surfactant and polymer layers around the bubbles are investigated as a part of drilling fluids and their positive effect on the formation damage is proven. Stability of the bubbles in the fluid is very important, and the optimum surfactant and polymer types should be chosen at optimum concentrations. In this work, an attempt is made to analyze the stability of bubbles of the drilling fluid, based on the diffusive mass transfer concept. Mass transfer and interfacial mass transfer coefficients become more important when surfactant concentration gradient exists in micro‐bubble layers. Interfacial mass transfer coefficients have an important effect on mass transfer phenomena in Aphron fluids system; so, the precise selection of these coefficients results in the conformity of modeling and experiments. We can say that reducing the mass transfer rate from bubble layers will result in stable bubbles in the fluid and, thus, the efficiency of the fluid during drilling will not decrease. It is shown that the interfacial mass transfer coefficient decreases with an increase in surfactant concentration.     

溶气式泡载分离器内减压成泡过程

通过对压力饱和溶气水减压成泡过程的热力学分析表明,溶气压力越高,形成气泡越细密,释气较完全。采用Kolmogoroff各向同性湍流理论得出湍流场中气泡稳定存在的条件和气泡大小随操作条件的变化规律。实验考察了操作条件对气泡分布的影响,采用Gamma分布能较好地描述实验。     

Hydrogen and Oxygen Bubble Attachment to a Bitumen Drop

Air bubble – bitumen attachment is a critical step in the flotation of bitumen from mined oil sand. In this study, single bubble – bitumen drop attachment was observed directly using a novel experimental technique. Induction time is determined and used as an indication of bubble‐bitumen attachment potency for both hydrogen and oxygen bubbles. The attachment tests were conducted in deaerated municipal water (City of Edmonton tap water) at temperatures ranging from 22–50°C. Induction times measured for hydrogen bubble attachment were shorter than those for oxygen bubbles. Coalescence tests were also conducted in the absence of bitumen, and showed that hydrogen bubbles coalesced more rapidly than oxygen bubbles in both deaerated municipal water and clear (solids‐free) process water.     

Improving the dewetability characteristics of hydrophobic fine particles by air bubble entrapments

The present study deals with the role of surface hydrophobicity and air bubble entrapment on filtration / dewatering of fine coal particles (− 0.5 mm). The experimental results showed that hydrophobizing reagents increased the contact angle (or hydrophobicity) and decreased the filtrate surface tension, cake formation time and moisture content of the fine particles. In addition to these, when the air bubbles were introduced to the hydrophobic fine coal particles in water, the cake formation time and moisture content of the filter cake were further reduced, which may be attributed to the fact that micro/nano size air bubbles were entrapped on the surface of the fine particles in a slurry and increased the dewetting characteristics of the fine particles. As a result, this process may lower the amount of moisture trapped during the dewatering fine particles and increase the efficiency of the filters.     

微细气泡技术标准体系探究

微细气泡技术是面向未来、绿色可持续的技术.气泡尺寸小到微纳米级的微细气泡技术快速发展,其应用也越来越广泛,在矿物浮选分离、超声造影剂、污水处理、工业清洗和精细剥离、日用清洗和护肤、农业种植以及水产养殖、盐碱地改良和土壤修复等诸多领域,微细气泡技术均颇有建树.但是,就像其他新兴技术发展初期一样,伴随着微细气泡的研究和应用...     

单孔及微孔曝气低气速鼓泡床内气泡行为比较

引言鼓泡床反应器被广泛应用于吸收、液相氧化、好氧生化等气液反应过程,气体在液相中的分散情况对鼓泡床的反应和传质特性都有很大影响.为了提高气液传质效率,增加生产强度,工业反应器很多都是在高气速下操作(Ug>0·05m·s-1),很多研究都集中在高气速湍动鼓泡区[1~3].但对有机     

PPTA的逆流水洗工业化装置及改进

介绍了聚对苯二甲酰对苯二胺(PPTA)树脂的逆流水洗工业化装置及其工艺流程,并提出了改进措施。结果表明:采用真空带式逆流水洗机对PPTA树脂进行了水洗,使用工业纯水作为洗涤介质,经7～8级水洗,水洗液中的氮甲基吡咯烷酮(NMP)质量分数达40%以上,水洗效果好;通过在真空带式逆流水洗机后增设2级搅拌水洗装置,水洗后PPTA树脂的灰分含量可降至300μg/g,满足PPTA树脂工业化生产要求。     

密相流化床中介尺度流动结构的流体力学特性研究

在一套流化床冷模实验装置中对黄沙颗粒和黄沙-硅微粉 （20 μm）混合颗粒进行实验。测量固含率时间序列信号并进行统计分析,提出并建立复杂光纤脉动信号的解耦方法,实现稠密气固流中介尺度流动结构的准确识别。基于统计矩一致性原理提出气泡阈值的计算方法,通过遍历法确定气泡阈值。对气泡阈值变化规律进行分析,发现加入细颗粒有助于改善流化质量,随表观气速的增加,气泡阈值减小。对气泡、乳化和聚团三相的相分率进行统计,发现在黄沙颗粒中加入少量（5%,质量分数）细颗粒能够显著改善流化质量,细颗粒添加量过多时（10%）,对流化质量的改善将减弱。对气泡的流体力学特性进行分析,发现加入10%硅微粉后,气泡弦长增大,频率降低,速度略有降低。对颗粒聚团流体力学特性进行分析,发现随硅微粉含量增加,表观气速对聚团速度的影响减弱,聚团弦长略有减小。加入5%硅微粉后,颗粒聚团的出现频率较小且径向上分布均一。加入10%硅微粉后,聚团频率有所增大,说明加入过多硅微粉会促进聚团的形成。     

黏性流体中单气泡的运动特性

采用高速CCD成像技术实验测定了单个气泡在水及不同黏度甘油水溶液中的形变特性及上升终速度.结果表明,随着液相黏度的增加,小气泡均能呈良好球形,而大气泡则由类似椭球形的不规则形状逐渐向球帽形转变;气泡的周期性振荡趋于平缓,气泡上升终速度降低.提出了计算气泡上升终速度的关联方程,其预测结果与实验值吻合良好.     

改变工艺流程提高精煤产率降低副产品损失

通过取消沫煤机、旋流器等设备,简化了流程,使粉煤系统的工艺更趋合理,提高精煤产率,获得了明显的经济效益.