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1.
为丰富和发展表面活性剂减阻体系,研究了阳离子Gemini表面活性剂丙撑基双(十八烷基二甲基氯化铵)(18-3-18)与水杨酸钠(NaSal)组成的新型胶束体系的流变和减阻性能。考察了不同浓度胶束体系的流变特性,讨论了该胶束体系的摩擦阻力系数和减阻率随广义雷诺数的变化关系,并比较了在光滑管及粗糙管中该体系的减阻效果。结果表明,18-3-18/NaSal胶束体系具有良好的黏弹性、触变性和剪切变稀性。随胶束体系浓度增大,减阻效果提高。对18-3-18/NaSal(5 mmol L 1/10 mmol L 1)胶束减阻体系,存在临界广义雷诺数,最大减阻率为78.5%;对18-3-18/NaSal(7.5mmol L 1/15 mmol L 1,10 mmol L 1/20 mmol L 1)胶束体系在光滑管中的最大减阻率可分别达到82.3%和81.7%。该胶束体系在光滑管中的减阻效果优于粗糙管中的减阻效果,表明18-3-18/NaSal胶束是一种新型减阻胶束体系。  相似文献   

2.
通过矩形管道压降实验研究了壁面微沟槽和表面活性剂的减阻性能及联合减阻的增益效果,用粒子成像测速仪分析了流场特性。实验所用的微沟槽为3种不同结构的顺流向V形沟槽,表面活性剂为十六烷基三甲基氯化胺(CTAC),水杨酸钠(NaSal)作为补偿离子。结果表明,壁面微沟槽和表面活性剂溶液均有减阻效果,二者耦合后减阻率进一步提升,最高减阻率为48.26%。微沟槽的减阻性能主要作用在近壁区,通过影响边界层平均流速、速度脉动强度和涡结构,减少表面活性剂的湍动能损耗。当超过表面活性剂的临界雷诺数后,沟槽尖端的高剪切力会加剧胶束结构分解。表面活性剂能抑制湍流涡的演变,扩大微沟槽有效减阻的雷诺数范围。  相似文献   

3.
在全球能源紧张的背景下,“过程节能”手段的探索具有重要意义。消防工作在国民经济和社会发展中占据重要地位,将添加剂湍流减阻技术引进到消防系统,能提高消防水的射出速度和射程,在提高灭火效率的同时节省水泵功耗。根据消防水流特点,初步选定聚氧化乙烯/十八烷基三甲基氯化铵的聚合物/表面活性剂复配体系作为研究对象,借助介观分子动力学模拟手段,计算了此体系的抗剪切能力及表面张力。发现此体系的抗剪切能力较聚合物、表面活性剂单一体系有明显提升,且体系的表面张力较纯表面活性剂溶液有所提高,初步证明此体系适用于消防减阻。同时从分子动力学角度深入分析了复配体系内聚合物、表面活性剂分子之间的作用机制,可为进一步寻找适用于消防减阻的聚合物/表面活性剂复配添加剂体系提供理论指导。  相似文献   

4.
魏进家  姚志强 《化工学报》2007,58(2):335-340
利用ARES流变仪对具有湍流减阻作用的阳性界面活性剂CTAC/NaSal水溶液的剪切黏度进行了测量。溶液的质量浓度范围为5×10-5 ~2×10-4,温度范围为20~40℃。对实验数据的分析发现,Giesekus模型可较好地拟合不同浓度和温度下界面活性剂溶液的剪切黏度。得到了不同溶液浓度下Giesekus模型参数与温度的关联式,从而揭示了溶液减阻特性与其流变特性的内在联系。利用对向喷嘴装置RFX流变仪对CTAC/NaSal水溶液的拉伸黏度进行了测量。  相似文献   

5.
新型羟基磺基甜菜碱表面活性剂与相对分子质量为2 500万的聚丙烯酰胺进行复合,测定体系的界面张力、黏弹性及乳化性能。结果表明,新型羟基磺基甜菜碱表面活性剂在浓度2.16 mmol/L时,表面张力33.39 m N/m,且乳化性能较好,具有较好的表面活性剂性能。相比于单独的表面活性剂,二元复合体系使溶液的临界胶束浓度增大,且界面张力也升高。当表面活性剂浓度为1.3 g/L,聚合物浓度为0.5 g/L时,体系的界面张力达到最低。聚合物的加入能显著降低体系的粘弹性,且随着聚合物浓度的增加,出现黏度最大值的表面活性剂的浓度越低。当表面活性剂水溶液质量浓度1.3 g/L,聚合物浓度1.5 g/L时,体系乳化性能最佳,实验表明,在低渗透岩心中,可以提高采收率5.78%。  相似文献   

6.
新型羟基磺基甜菜碱表面活性剂与相对分子质量为2 500万的聚丙烯酰胺进行复合,测定体系的界面张力、黏弹性及乳化性能。结果表明,新型羟基磺基甜菜碱表面活性剂在浓度2.16 mmol/L时,表面张力33.39 m N/m,且乳化性能较好,具有较好的表面活性剂性能。相比于单独的表面活性剂,二元复合体系使溶液的临界胶束浓度增大,且界面张力也升高。当表面活性剂浓度为1.3 g/L,聚合物浓度为0.5 g/L时,体系的界面张力达到最低。聚合物的加入能显著降低体系的粘弹性,且随着聚合物浓度的增加,出现黏度最大值的表面活性剂的浓度越低。当表面活性剂水溶液质量浓度1.3 g/L,聚合物浓度1.5 g/L时,体系乳化性能最佳,实验表明,在低渗透岩心中,可以提高采收率5.78%。  相似文献   

7.
合成了胶原基有机硅表面活性剂(CBES),并研究了CBES的表面张力、临界胶束浓度、HLB值、乳化性能以及与非离子表面活性剂异构十三醇聚氧乙烯醚复配后的表面活性和乳化性能。通过吊片法测得CBES可使水的表面张力降低至30.5 mN/m,临界胶束浓度为0.44 g/L;采用乳化法测定CBES的HLB值为14~15,表明CBES为水溶性表面活性剂。此外,CBES乳化大豆油、氨基硅油和聚醚硅油的乳化率分别为10.5%,48.7%和90.0%,且与异构十三醇聚氧乙烯醚复配在乳化效力上具有协同增效作用。  相似文献   

8.
合成了一种耐温抗盐表面活性剂,通过红外光谱分析了该表面活性剂的结构。将其与2500万分子量聚丙烯酰胺进行复配,考察了复配体系的表面、界面性能。研究结果表明:所合成的产物为目标产物;磺基甜菜碱表面活性剂的临界胶束浓度(cmc)为2.19×10^-3mol/L,临界胶束浓度下的表面张力(γcmc)为25.51mN/m;加入聚合物后临界胶束浓度变为4.09×10^-3mol/L,γcmc变为26.65mN/m;表面活性剂质量浓度在0.8—1.5g/L,可使胜利原油油水间的界面张力达到超低数量级(10^-3mN/m);聚合物的加入有利于乳状液的形成。  相似文献   

9.
两性/阴离子表面活性剂复配体系性能研究   总被引:4,自引:1,他引:3  
采用环氧氯丙烷与磷酸二氢钠反应制备中间体,再与十二叔胺反应,制备甜菜碱型磷酸酯两性表面活性剂,并与十二烷基苯磺酸钠(SDBS)进行复配。测定复配前后产品的表面张力、临界胶束浓度、泡沫稳定性和乳化能力等性能。结果表明,在最佳合成工艺条件下,甜菜碱型磷酸酯两性表面活性剂的表面张力为30 mN/m,临界胶束浓度为7.98 g/L。对于复配体系,当甜菜碱型磷酸酯表面活性剂与SDBS以质量比6∶4进行复配时增效作用最好,其表面张力为23 mN/m,临界胶束浓度为4.84 g/L,对松节油的乳化性能较好。  相似文献   

10.
以无患子为原料,提取得到天然表面活性剂无患子皂苷,研究其与阳离子表面活性剂十六烷基三甲基溴化胺(CTAB)的复配性能,并将无患子皂苷和复配表面活性剂用于溶剂热法制备氢氧化镍复合材料。考察了反应溶剂、温度和表面活性剂对材料形貌的影响。研究表明:复配体系具有优异协同增效作用,当无患子皂苷与CTAB以质量比50:50复配时,表面活性剂溶液的临界胶束浓度(CMC)及临界胶束浓度下对应表面张力(γCMC)分别由无患子皂苷的1 g/L和41.97 mN/m大幅度降低到0.18 g/L和24.63 mN/m。对氢氧化镍复合材料的形貌分析及XRD分析结果显示:在乙醇体系中,以无患子皂苷为表面活性剂,180℃时制得形貌均匀的具有孔隙花球状微球结构复合材料,其纳米片多且厚;以无患子皂苷/CTAB复配体系为表面活性剂,在乙醇体系中,140℃制得形貌均匀的珊瑚球形复合微纳米材料;两种不同形状的氢氧化镍复合材料均为Ni(OH)2/NiOOH型复合材料。  相似文献   

11.
Turbulent drag reduction behaviour of a mixed nonionic polymer/cationic surfactant system was studied in a pipeline flow loop to explore the synergistic effects of polymeric and surfactant drag reducing additives. The nonionic polymer used was polyethylene oxide (PEO) at three different concentrations (500, 1000, and 2000 ppm). The surfactant used was cationic octadecyltrimethylammonium chloride (OTAC) at concentration levels of 1000 and 2500 ppm. Sodium salicylate (NaSal) was used as a counter‐ion for the surfactant at a molar ratio of 2 (MR = Salt/OTAC = 2). Relative viscosity and surface tension were measured for different combinations of PEO and OTAC. While the relative viscosities demonstrated a week interaction between the polymer and the surfactant, the surface tension measurements exhibited negligible interaction. The pipeline results show a considerable synergistic effect, that is, the mixed polymer–surfactant system gives a significantly higher drag reduction (lower friction factors) as compared with pure polymer or pure surfactant. The addition of surfactant to the polymer always enhances drag reduction. However, the synergistic effect in mixed system is stronger at low polymer concentrations and high surfactant concentrations. © 2011 Canadian Society for Chemical Engineering  相似文献   

12.
表面活性剂减阻由于其机械、化学、光、热稳定性 ,越来越为工程界所重视。文中开展了目前较少研究的中等质量分数 (采用 170、 80 0 μg g两种质量分数的溶液 )CTAC (Cetyltrimethylammoniumchloride,十六烷基三甲基氯化铵 )溶液与伴随离子 (Sal+ )共存条件下的减阻实验。研究表明 ,在一定CTAC及伴随离子质量分数范围内 ,溶液的减阻性能随CTAC及伴随离子质量分数的增加而下降 ;伴随离子在高雷诺数区域对减阻效应几乎没有影响 ;溶液的减阻性能曲线没有明显的“发生 (onset)”点。对以上实验观测到的现象机理进行了探讨  相似文献   

13.
Although extensive research work has been carried out on the drag reduction (DR) behaviour of polymers and surfactants alone, little progress has been made on the synergistic effects of combined polymers and surfactants. In this work, the interactions between drag‐reducing anionic polymer (copolymer of acrylamide and sodium acrylate, referred to as PAM) and drag‐reducing cationic surfactant (octadecyltrimethylammonium chloride, OTAC) are studied. Solutions are prepared using both deionised (DI) water and tap water. The measurement of the physical properties such as electrical conductivity and viscosity are used to determine the surfactant–polymer interactions. The addition of surfactant to the polymer solution has a significant effect on the properties of the system. The critical micelle concentration (CMC) of the mixed surfactant–polymer system is found to be different from that of the surfactant alone. With the addition of surfactant to a polymer solution, a substantial decrease in the viscosity occurs. The observed changes in the viscosity of mixed polymer–surfactant system are explained in terms of the changes in the extension of polymeric chains, resulting from polymer–surfactant interactions. The anionic PAM chains tend to collapse upon the addition of cationic OTAC. The pipeline flow behaviour of PAM/OTAC mixtures is found to be consistent with the bench scale results. The DR ability of PAM is reduced upon the addition of OTAC. At low concentrations of PAM, the effect of OTAC on the DR behaviour is more pronounced. The DR behaviour of polymer solutions is strongly influenced by the nature of water (DI or tap). © 2011 Canadian Society for Chemical Engineering  相似文献   

14.
用阳离子聚丙烯酰胺(CPAM)分别插层改性钠基膨润土及十六烷基三甲基溴化铵(CTMAB)有机膨润土,分析了改性膨润土的结构,并研究了其对模拟及实际印染废水的脱色性能.结果表明,CPAM复合插层改性的CTMAB有机膨润土的层间距d001(20.480A)大于CTMAB有机膨润土(19.211A)、CPAM改性膨润土(13,604A)和钠基膨润土(13.270A)的层间距.用100mgCPAM复合插层改性膨润土处理200mL(30mg/L)活性艳红K-2G模拟染色废水时,脱色率达99%以上;处理实际印染废水时,脱色率可以达到94%,表现出优良的吸附、脱色、絮凝沉降的协同作用.  相似文献   

15.
摘要:以一种功能性疏水单体与丙烯酰胺(AM)、丙烯酸(AA)和2-丙烯酰胺-2-甲基丙磺酸(AMPS)为原料,合成了一种疏水缔合聚合物HAWP-18。采用流变仪考察了疏水缔合聚合物HAWP-18的耐剪切性能、黏弹性及触变性,结果表明,HAWP-18属于假塑性流体,临界缔合浓度为2.31g/L,表现出较强的耐剪切性能;黏弹性测试表明,HAWP-18是典型的黏弹性结构流体,具有较宽的线性黏弹区,该体系的储能模量G''大于损耗模量G'',并且黏度越大,弹性特征越强;采用稳态剪切测试研究了不同质量浓度HAWP-18的剪切应力与剪切速率的关系,HAWP-18具有触变性,并且触变性随质量浓度增大而增强;使用自制摩阻测试仪测定了不同质量浓度HAWP-1的减阻性能,结果表明,HAWP-18减阻率随质量浓度的增加先上升后降低。HAWP-18的耐剪切性及其良好的黏弹性、触变性和减阻性能为其应用于压裂液提供了实验支撑。  相似文献   

16.
减阻型纳米流体在圆管内的流动和换热特性   总被引:1,自引:1,他引:0       下载免费PDF全文
孙斌  张志敏  杨迪  李洪伟 《化工学报》2015,66(11):4401-4411
实验测定了在Reynolds数4000~16000范围内,质量分数0~0.5%的石墨、多壁碳纳米管、Al2O3、Cu、Al、Fe2O3、Zn纳米粒子加入到100~400 mg·kg-1浓度的十六烷基三甲基氯化铵(CTAC)减阻剂中所制备的减阻型纳米流体的摩擦阻力系数和对流传热系数。结果表明:在CTAC中加入水杨酸钠(NaSal)与去离子水所配制的减阻剂具有一定的稳定性和很强的减阻特性,当减阻剂浓度为200 mg·kg-1时其减阻特性最优。石墨纳米粒子在增强对流换热和减少流动阻力方面具有较佳的综合性能,当石墨纳米颗粒质量分数为0.4%时,其综合性能因子K是去离子水的5倍。最后给出了减阻型石墨纳米流体在圆管内的流动阻力和换热关联式,其计算值和实验值吻合良好。  相似文献   

17.
Skin–friction drag accounts for a large portion of resistance encountered by water‐based vehicles, such as ships and submarines. Developing drag reduction methods to improve drag reduction performance has drawn worldwide attention recently. UV‐induced polymerization has been investigated as a way to graft the drag reduction agent PAM on to a PVC substrate with a biomimetic riblet surface. The effects of AM concentration and irradiation time on the grafting rate were explored to determine optimal grafting parameters. UV grafting polymerization was clarified by comparing the peak absorption variation of the infrared spectrum before and after grafting. The PAM thin film grafted on riblet surface was measured approximately 10 µm in thickness. A rotating disk apparatus was built to measure the synthetic drag reduction performance. The drag reduction rate of the grafted PAM riblet surface was tested at approximately 14%, higher than the 6% of the traditional riblet surface. Moreover, the excellent drag reduction performance of grafted PDMS riblet surface lasted for 12 days. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42303.  相似文献   

18.
In the paper, the hydrophobic associating polymer ACS-210 was prepared by solution polymerization of acrylamide, acrylic acid, salt-resisting monomer and hydrophobic monomer. Chemical structure and properties of the polymer was characterized by FTIR, TGA and XRD. The rheological property of ACS-210 solution was investigated by rheometer. The frictional resistance of the ACS-210 solutions at different application condition was examined using friction testing system. Results showed that the thermal stability of polymer ACS-210 increases and crystallinity of ACS-210 declines after incorporating of hydrophobic monomer. The viscosity of ACS-210 solution of different concentration decreased with prolonging the shearing time and the retention rate of viscosity is relatively high after long shearing time. The relation curve between the viscosity of polymer solution and shear rate followed the power law model. When the concentration of ACS-210 aqueous solution was less than the critical associating concentrations, storage modulus G’ is less than loss modulus G”, the association was weaker between the molecular chains, and the effective spatial structure did not form. After increasing the concentration of the polymer solution, G’ is more than G”, the degree of association of polymer is stronger. The synthesized polymer has favorable drag reduction effect. The molecular weight is not the only factor to determine drag reduction efficiency. The hydrophobic association can also improve the drag reduction efficiency.  相似文献   

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