纤维对水基泡沫液稳定性影响的研究

探讨了蔗渣浆、阔叶木浆和针叶木浆漂白后的纤维原料对水基泡沫液的发泡能力和稳定性的影响,并采用光学显微镜与Image J软件结合的方法,着重研究了水基泡沫液中气泡大小及其分布情况。结果表明,较宽的纤维长度分布有利于水基泡沫液的发泡性能;纤维长、多分散性数值大的水基泡沫液的稳定性好,气泡直径较小且大小均匀;3种浆料中,蔗渣浆纤维的水基泡沫液稳定性最差,其次是阔叶木浆纤维的水基泡沫液,针叶木浆纤维的水基泡沫液稳定性最好。     

泡沫性能评价方法及稳定性影响因素综述

综述了测试泡沫性能(即发泡性和稳定性)的方法,并讨论了各方法的优缺点。评述了泡沫稳定性的影响因素,并探讨了如何改变泡沫稳定性的方法。     

日用化学品泡沫性能的多维度评价方法研究

介绍了动态泡沫分析的测试方法和测试原理，并开展了表面活性剂常用原料、洗衣液、洗发水和牙膏等常规日化产品的泡沫性能研究。在动态泡沫的测试中，基于不同样品设置了差异化的测试程序，监测了整个测试周期内泡沫高度、泡沫体积、每平方毫米气泡个数、气泡平均面积、气泡平均半径等参数随时间的演化关系，计算出体积消泡率、气泡个数变化率等反映泡沫稳定性的相关参数。利用高度测试模块中泡沫体积、泡沫高度等参数的分析评价了各样品的发泡能力；通过结构测试模块中气泡个数、平均气泡面积、平均气泡半径等参数的分析评价了各样品的泡沫微观特性；同时结合高度测试和结构测试双模块中持久值、体积消泡率、气泡个数变化率、半衰期等多角度评价了各样品的泡沫稳定性。由此经双模块测试中各参数的协同分析实现了产品发泡快慢、泡沫多少、泡沫大小和稳定性等泡沫性能的多维度评价。     

油相对含氟磺基甜菜碱泡沫性能影响研究

为了研究油相对氟碳表面活性剂泡沫性能的影响,使用气流法探讨了含油量和气液比对不同浓度的含氟磺基甜菜碱体系的泡沫性能,并通过测量表面与界面张力来分析该泡沫体系在油作用下的消泡方式。结果表明,在表面活性剂质量浓度由0.3%减至0.05%,含油体积由10%增至40%,气液比由3∶1减至1∶3的各个过程中,泡沫的起泡能力和稳定性都下降,一定条件下起泡能力受泡沫稳定性影响。发现假乳状液膜理论能很好的解释泡沫稳定性实验结果。在该泡沫体系中油通过形成不稳定的油桥使泡沫膜破灭。     

油相对含氟磺基甜菜碱泡沫性能影响研究

为了研究油相对氟碳表面活性剂泡沫性能的影响,使用气流法探讨了含油量和气液比对不同浓度的含氟磺基甜菜碱体系的泡沫性能,并通过测量表面与界面张力来分析该泡沫体系在油作用下的消泡方式。结果表明,在表面活性剂质量浓度由0.3%减至0.05%,含油体积由10%增至40%,气液比由3∶1减至1∶3的各个过程中,泡沫的起泡能力和稳定性都下降,一定条件下起泡能力受泡沫稳定性影响。发现假乳状液膜理论能很好的解释泡沫稳定性实验结果。在该泡沫体系中油通过形成不稳定的油桥使泡沫膜破灭。     

原油对水相泡沫稳定作用机理研究进展

为了评述原油对水相泡沫稳定性的影响机理,分别介绍了原油在水相泡沫中的存在状态,原油对泡沫的稳定或破坏机理。原油对泡沫的稳定性有着显著影响,稳泡或消泡也极大程度上决定了石油与天然气开采作业中,诸如泡沫驱油、泡沫堵水、堵气、泡沫排液、泡沫压裂等作业效率。重点阐述了假乳液膜对泡沫稳定性的影响机理,总结出原油在水相泡沫体系中以溶解油或乳化油两种状态存在。原油溶解于水相胶束中(溶解油)可降低泡沫的稳定性。大多原油在水相泡沫中以乳化油滴形式存在,油滴与气泡之间被假乳液膜隔开,假乳液膜决定了泡沫体系的稳定性。假乳液膜稳定性好能促进三相泡沫的稳定性;而假乳液膜稳定性差就加剧了三相泡沫地破裂。通过评述指出了原油与水相泡沫相互作用研究领域今后的研究方向。     

短链两亲分子活性剂制备氮化硅泡沫陶瓷

采用直接起泡法制备氮化硅泡沫陶瓷,研究了长链表面活性剂与短链两亲分子活性剂对泡沫稳定性的影响,分析了Si3N4泡沫陶瓷的微观结构。结果表明：与长链表面活性剂稳定的泡沫相比,短链两亲分子稳定的泡沫稳定性较好,泡体呈现球形或椭球形。通过控制发泡工艺制备出气孔尺寸分布均匀的开孔和闭孔两种不同孔结构的多孔氮化硅泡沫陶瓷,闭孔氮化硅泡沫陶瓷的气孔率和抗弯强度分别为40%和106MPa;开孔氮化硅泡沫陶瓷的气孔率和抗弯强度分别为80%和28MPa。     

泡沫流体稳定性受温度影响分析

实验研究了温度对泡沫剂泡沫稳定性的影响。从微观层面分析了温度对泡沫流体的影响。结果是:随着温度的升高,泡沫剂溶液的发泡体积先增加,然后趋于最大值,后又有所下降,但是变化幅度很小,各种泡沫剂的半衰期均成下降的趋势;低温和高温下的泡沫衰变机理不同;高温时较长的疏水基团对泡沫的稳定性有促进作用,较长的烷基链对于泡沫的稳定性有利,但烷基链太长,对泡沫的稳定性是不利因素。     

明胶溶液浓度对其发泡性能的影响

明胶具有发泡性能,该性能在食品、医药、洗涤、化妆品等行业具有很好的潜在应用价值。明胶浓度对其体系的发泡性能和发泡稳定性产生的影响,将直接影响到其产品的质量和性能。因此,本文采用搅拌法,在60℃水浴条件下,采用100mL明胶溶液,研究了明胶溶液浓度对其发泡性能和泡沫稳定性的影响。实验结果表明:在相同的温度和转速条件下,随着明胶溶液浓度的增加,其发泡量逐渐减少,而泡沫稳定性则越来越好。A型明胶溶液浓度为1%时发泡量最大,最大值为71mL;在浓度为9%时泡沫半衰期为86min,表现出较好的泡沫稳定性。B型明胶溶液浓度为1%时发泡量最大值为52mL;溶液浓度为9%时泡沫半衰期为3min。A型明胶和B型明胶两者相比,A型明胶具有更好的发泡性能及泡沫稳定性。     

泡沫起泡性、稳定性及评价方法

本文论述了泡沫的两个基本性质:起泡性和稳定性。对起泡性和提高泡沫稳定性的方法作了评价。     

泡沫稳定剂增强泡沫稳定性的研究

泡沫是气体分散于液体中的多相分散体系。气体是分散相,液体是分散介质。制备泡沫的过程中,液体中的气泡在密度差的作用下易在液面上形成以少量液体构成的液膜隔开气体的气泡聚集物——泡沫。泡沫流体是气体组成的气泡分散体系,具有极高的表面自由能,是热力学不稳定体系,所以泡沫会发生衰变,原因普遍认为有两方面：泡沫中液体的析出和气体穿透液膜扩散。泡沫以其独特的性能在钻井、采油、采气、消防等领域中得到越来越多的应用,如泡沫驱油、泡沫钻井、泡沫水泥固井、泡沫酸酸化、泡沫冲沙洗井、泡沫压裂、泡沫采气、蒸汽驱泡沫调剖、泡沫-聚合物复合驱等,     

Simple and generally applicable method of determination and evaluation of foam properties

A new, simple foam test, in which a well-controlled volume of gas is introduced into a definite volume of solution, is presented along with the method of analysis. Aqueous solutions of sodium dodecyl sulfate (SDS), n-octyl-β-d-glucopyranoside, hexadecyltrimethylammonium bromide (CTAB), and n-hexanol, i.e., four systems forming metastable and transient foams, were studied. The parameter R5, defined as the ratio of the height of the foam at 5 min after formation to the initial height, is proposed for the evaluation of foam stability. Foams having R5 values higher than 50% can be considered as metastable. Lower R5 values indicate low-stability foams. Changes of R5 values with concentration are similar to those of foam half-life with concentration. Thus, instead of measurements lasting hours for the foam half-life, one can obtain similar information from tests lasting only a few minutes. With this test also one can obtain information about the solution contents in foams. This parameter can be used as an additional criterion for the evaluation of foam stability. In the case of metastable foams formed by SDS, CTAB, and n-octyl-β-d-glucopyranoside, the initial foam volume was almost equal to the volumes of the dispersed gas and the solution carried into the foam by the bubbles. This shows that there was practically no rupture of foam films at the stage of the foam formation.     

Research on the influence of wollastonite fibers on the stability of foam extinguishment agent and its effect on the extinguishing efficiency of pool fire

Aqueous film-forming foam (AFFF) is a frequently used foam extinguishment agent for oil fires, but the foam stability of AFFF is not perfect, which results in poor fire extinguishing performance. In order to improve the foam stability of AFFF, wollastonite fibers were explored to increase the performance of foam extinguishment agent. The influences of wollastonite fibers' concentration on foam extinguishment agent's stability are studied. When the concentration of wollastonite fibers is 30.00 g/100 mL, the drainage time is prolonged, which is the best among all the formulas. Moreover, the fire resistance and fire-fighting performances are increased significantly due to the incorporation of wollastonite fibers. In order to reveal the effect of wollastonite fibers on the stability of foam extinguishment agent, the structure of the foam and the diameter of the bubbles are investigated. The results show that the complexity and compactness of foam layer's structure are very important for foam stability, and the fire-extinguishing performance is improved due to the introduction of wollastonite fibers.     

Stabilization of natural gas foams using different surfactants at high pressure and high temperature conditions

Natural gas foam can be used for mobility control and channel blocking during natural gas injection for enhanced oil recovery, in which stable foams need to be used at high reservoir temperature, high pressure and high water salinity conditions in field applications. In this study, the performance of methane (CH₄) foams stabilized by different types of surfactants was tested using a high pressure and high temperature foam meter for surfactant screening and selection, including anionic surfactant (sodium dodecyl sulfate), non-anionic surfactant (alkyl polyglycoside), zwitterionic surfactant (dodecyl dimethyl betaine) and cationic surfactant (dodecyl trimethyl ammonium chloride), and the results show that CH₄-SDS foam has much better performance than that of the other three surfactants. The influences of gas types (CH₄, N₂, and CO₂), surfactant concentration, temperature (up to 110°C), pressure (up to 12.0 MPa), and the presence of polymers as foam stabilizer on foam performance was also evaluated using SDS surfactant. The experimental results show that the stability of CH₄ foam is better than that of CO₂ foam, while N₂ foam is the most stable, and CO₂ foam has the largest foam volume, which can be attributed to the strong interactions between CO₂ molecules with H₂O. The foaming ability and foam stability increase with the increase of the SDS concentration up to 1.0 wt% (0.035 mol/L), but a further increase of the surfactant concentration has a negative effect. The high temperature can greatly reduce the stability of CH₄-SDS foam, while the foaming ability and foam stability can be significantly enhanced at high pressure. The addition of a small amount of polyacrylamide as a foam stabilizer can significantly increase the viscosity of the bulk solution and improve the foam stability, and the higher the molecular weight of the polymer, the higher viscosity of the foam liquid film, the better foam performance.     

二氧化碳泡沫稳定性及聚合物对其泡沫性能的影响

基于CO₂气体性质的特殊性以及CO₂泡沫在多孔介质中表现出不同于其他气体泡沫的现象,利用气流法,选用十二烷基苯磺酸钠（SDBS）作为起泡剂,研究了CO₂泡沫的稳定性和衰减规律,以及聚合物部分水解聚丙烯酰胺（HPAM）对CO₂泡沫性能的影响。结果表明,在相同条件下,CO₂泡沫的稳定性比N₂泡沫差,并且CO₂泡沫的稳定性基本不受表面活性剂浓度的影响;CO₂泡沫的衰减曲线近似一条直线,泡沫形成后体积迅速减小。CO₂在水中具有较大的溶解度,泡沫的液膜渗透率系数大,因而泡沫稳定性差,也是造成CO₂泡沫在岩心内渗流规律区别于N₂泡沫的一个重要原因。HPAM的加入可以在一定程度上增强CO₂泡沫的稳定性,但同时也会使溶液起泡性能降低,所以实际应用时需要综合考虑泡沫特性,选择最佳的聚合物浓度。     

起泡剂的起泡性能及使用浓度优选研究

起泡剂的起始发泡体积和泡沫稳定性是决定起泡剂起泡性能的两个重要因素,也是实际应用当中筛选起泡剂的重要指标.采用Ross-Miles法对13种不同类型起泡剂在常温下的起泡性能进行了评价.结果表明：不同类型起泡剂的起始发泡体积和泡沫稳定性具有显著的不同.不同起泡剂的起始发泡体积随浓度的增加而增大.当起泡剂浓度增加到0.5％时,起始发泡体积趋于稳定,由此确定起泡剂的最佳使用浓度为0.5％.     

温度对高浓度SDS水溶液泡沫稳定性及分离的影响

高浓度表面活性物质的分离是泡沫分离过程的难题,也是制约泡沫分离技术应用于工业化生产的瓶颈.为了解决高浓度表面活性物质泡沫分离的难题,以阴离子表面活性剂十二烷基硫酸钠(SDS)水溶液为体系,研究了在其临界胶束浓度(CMC)附近时,温度对SDS水溶液气泡直径、泡沫稳定性、富集比及回收率的影响.结果表明:温度对高浓度表面活性物质的泡沫分离有显著影响.当SDS水溶液浓度分别为1.2、2.3、3.5g·L-1,温度从30℃升高到70℃时,泡沫稳定性先增大后减小,在pH 6.9、表观气速2.4×10-3 m·s-1、装液量200 mL的操作条件下,气泡直径先减小后增大,富集比提高了3～5倍,回收率降低了34％～65％.     

烷基糖苷的泡沫扫描研究

采用泡沫扫描方法全面研究了APG质量浓度、N2流量和NaC l质量浓度对APG泡沫性能的影响。结果表明,在1000 s内所有样品泡沫高度不变,稳泡性很好,除ρ(APG)=0.25 CMC泡沫时间为149 s外,其余质量浓度下发泡时间都在(144±2)s,随表面活性剂质量浓度增加,泡沫相对电导、泡沫最大密度和泡沫稳定指数值都增加。N2流量对体系发泡性能影响较大,最佳N2流量为40 mL/min。随盐含量增加发泡时间微减少,而泡沫稳定指数增加。在稳泡阶段,随时间延长和N2流量增加,泡沫数量越来越少,泡沫单个面积越来越大。盐含量高时泡沫数量较多。随表面活性剂质量浓度增加,泡沫数量增加,但泡沫总面积和平均面积减小。     

泡沫稳定剂在阻燃高回弹聚氨酯泡沫塑料中的应用

分别采用L-5 333,Y-10 366和B-8716三种泡沫稳定剂制备阻燃高回弹泡沫塑料;探讨了泡沫稳定剂对阻燃高回弹聚氨酯（FRHRPU）组合料反应活性、泡孔结构及制品力学性能的影响。结果表明：泡沫稳定剂Y-10 366制备的FRHRPU的拉伸强度为171.18 kPa,撕裂强度为3.23 N/cm和回弹性为58.70%,均高于其他两种硅油的,并且当Y-10 366与多元醇的质量比从0.5/100增加到1.2/100时,制品的泡孔孔径先减小后增大,而制品的开孔率从93%降低到35%。