柴油乳状液的稳定性及热破乳研究

以柴油乳状液模拟大庆油田三元复合驱油田采出水,采用瓶试法,考察了油水体积比,碱、表面活性剂、聚合物质量浓度,剪切速率,乳化时间对乳状液稳定性的影响,得到满足试验要求的柴油乳状液。使用恒温水浴锅加热破乳,采用激光粒度和Zeta电位仪测定粒径分布和Zeta电位,紫外可见分光光度计测定破乳后的柴油浓度。结果表明,破乳后水层含油量随着温度的升高而降低,平均粒径随着温度的升高而减小,60℃时的粒径分布峰随破乳时间而延长变宽,热破乳机理主要集中在降低油滴界面膜强度和降低体系黏度两方面。     

原油乳状液的破乳机理及破乳方法

归纳了近年来对原油乳状液破乳机理和破乳方法的研究进展,介绍了各种方法的特点、破乳机理和发展现状,对今后乳状液破乳工作的发展提出了建议。     

油水乳状液破乳技术研究进展

重点介绍了近年来乳状液破乳技术在破乳方法、破乳效果影响因素、破乳剂的开发等方面的研究进展,并分析总结了破乳技术研究存在的不足,提出了破乳技术研究的努力方向。     

乳状液膜静电破乳器破乳机理研究

分析了乳状液膜分离技术中静电破乳的主要影响因素 ,研究了乳状液在高压直流静电场和交流静电场中不同的破乳机理 ,结果表明 ,在高压直流静电场中需采用裸电极才能有效破乳 ,在交流静电场中使用裸电极或绝缘电极均可有效破乳     

乳状液超声凝聚破乳

以水为连续相、二氯乙烷为分散相,配制成稳定的乳状液,在超声驻波场条件下,对其进行凝聚破乳研究,重点考察超声声强、超声辐照时间、沉降时间、超声作用频率对乳状液破乳的影响。结果表明,超声声强的改变直接影响了乳状液分散相液滴的凝聚和发散,超声破乳的声强应在临界阈值以下;超声辐照时间存在一个最佳作用时间;超声频率对液滴凝聚有重要影响,根据体系黏度、密度、液滴粒径等性质计算了最佳超声凝聚频率,并通过了实验验证。设计了正交实验,综合考虑了能耗和破乳效率,得到该乳状液破乳最佳条件为：超声频率10 kHz、声强270 W•m^-2、辐照时间9 min、沉降温度40℃及沉降时间3 h。此条件下,其破乳率可达到91%。     

液膜乳状液连续电破乳研究

讨论了连续电破乳器的设计方法，在此基础上建立了竖式平板绝缘电极实验室用的连续电破乳装置。对于煤油－兰１１３Ｂ（表面活性剂）－ＺｎＳＯ＿４溶液体系，实验研究了各种因素对连续破乳的影响。结果表明，当乳液进破乳器的速度较小时，可以获得较高的油水分离效果。     

阳离子对稠油乳状液破乳的影响

以稠油为研究对象,考察了不同阳离子对稠油乳状液破乳效果的影响。测定了不同种类及含量的无机盐对稠油乳状液脱水率、黏度及油一水界面张力的影响。结果表明：二价离子ca^2＋,Mg^2＋可以促进破乳,一价离子Na^2＋对乳状液破乳影响不大,心对破乳有一定抑制作用。阳离子促进乳状液破乳能力由大到小依次为：Mg^2＋ca^2＋,Na^2＋,K^2＋。稠油乳液黏度、界面张力对破乳影响无规律性。     

聚醚破乳剂结构对二元驱乳状液破乳性能的影响

本文考察了破乳剂结构对模拟二元复合驱石油采出液破乳效果。结果表明:随着破乳剂支链化程度升高,破乳性能增强,具有超支化结构的聚酰胺-胺聚醚破乳剂的析水率最高,达到90%,但脱出水浑浊且存在较厚乳化中间层。聚酰胺-胺聚醚破乳剂与反相破乳剂协同作用提升破乳性能,最佳条件下析水率接近100%。     

超声与离心联用对乳状液破乳的研究

本文提出超声、离心联合作用于乳状液破乳的方法,采用正交实验研究离心时间、离心转速、超声破乳功率和超声破乳时间等因素对破乳效果的影响。研究表明,超声与离心联合作用可以使乳状液在较小的离心转速下,快速破乳。最佳工艺条件为：离心时间4min、离心转速1000r~min～、超声破乳功率40W、超声破乳时间2min,该条件下破乳率能达到97％。     

环己烷/水乳状液的超声破乳

为排除污油等复杂乳化液中的杂质干扰,采用单一组分方法,制备不同体系的环己烷/水乳状液,研究超声在乳状液中的破乳作用,考察超声声强、超声频率、超声辐照时间对乳状液破乳的影响。结果表明:乳状液的初始水含量对超声破乳效果有影响,初始水含量越低,破乳效果越好;超声声强的改变直接影响乳状液分散相液滴的凝聚和发散,超声破乳的声强应在空化临界阈值以下,以0.66 W/cm2最佳;超声辐照时间为6 min,超声频率为20 kHz时破乳效果达到最好。     

Deep desulfurization of hydrodesulfurized diesel oil by Pseudomonas delafieldii R‐8

Biodesulfurization is a promising technology for deep desulfurization. The remaining alkylated DBTs (dibenzothiophenes) in the HDS‐treated (hydrodesulfurized‐treated) diesel oil could be selectively and efficiently desulfurized by resting cells of Pseudomonas delafieldii R‐8, a Gram‐negative bacterium. The desulfurization activities of resting cells were greatly affected by W/O ratio (the volume ratio of aqueous phase to oil phase) and cell concentration. The desulfurization activity increased with the increase in the W/O ratio. When the W/O ratio and cell concentration were 2 and 25 mg cm^?3, the desulfurization activity was as high as 0.41 mg(total sulfur) g^?1(dry cell weight, DCW) h^?1, ie higher than that reported previously. GC‐AED (gas chromatography with an atomic emission detector) analysis showed that the total reductions for all the C1DBTs and C2DBTs were approximately 100%, 94.63% for C3DBT, and 97.09% for C4DBT (designated CxDBT, where x is the number of alkyl groups attached). The rates of biodesulfurization relate to the number and position of alkyl groups attached to the DBT. Copyright © 2005 Society of Chemical Industry     

Integration of flocculation and adsorptive immobilization of Pseudomonas delafieldii R‐8 for diesel oil biodesulfurization

BACKGROUND: Deep desulfurization of hydrocarbon fuels is receiving increasing worldwide attention because of the increasingly stringent regulations to meet the requirement of environmental protection. Biodesulfurization (BDS) is being explored as either an alternative or complementary process to the conventional oil refining technologies. The whole cell immobilization technique is of great importance for accelerating the industrialization of BDS. An effective technique for a BDS process employing flocculation and integration with immobilization was developed. RESULTS: Pseudomonas delafieldii R‐8 cells were successfully flocculated and immobilized by directly adding chitosan and celite into the culture broth. The one‐step immobilized R‐8 cells exhibited good catalytic activity and retained at least 85% activity after six cycles of repeated‐batch desulfurization. Extensive biodesulfurization of diesel oil resulted in 82% reduction of total sulfur from 123 to 22 µg g^?1 in 24 h. CONCLUSIONS: A novel and simple technique was developed using chitosan flocculation and integration with cell immobilization onto celite for dibenzothiophene BDS. The present report indicates that integration of flocculation and immobilization may provide a continuous and efficient method of BDS. Copyright © 2010 Society of Chemical Industry     

添加剂对柴油机润滑油油水界面性质及乳状液稳定性的影响

测定了柴油机油模拟油/蒸馏水体系的界面张力、界面剪切粘度和乳状液稳定性。结果表明,含有添加剂T154的柴油机油模拟油与蒸馏水间的界面张力明显低于无添加剂的体系的界面张力,界面剪切粘度增加,乳状液特性值比模拟油/蒸馏水体系稍大,乳状液稳定性增加;添加剂T109却使模拟油与蒸馏水体系的界面张力增大,界面剪切粘度降低,乳状液特性值比模拟油/蒸馏水体系小,乳状液稳定性降低,有一定的破乳作用。     

Temperature effect on the viscosities of palm oil and coconut oil blended with diesel oil

One of the major difficulties in using crude vegetable oils as substitute fuels in diesel engines is their relatively high viscosities. Increasing the temperature of the crude vegetable oil, blending it with diesel oil, or the combination of both offers a simple and effective means of controlling and lowering the viscosities of vegetable oils. This work reports viscosity data, determined with a rotational bob-and-cup viscometer, for crude palm oil and cononut oil blended with diesel oil over the temperature range of 20–80°C and for different mixture compositions. All the test oil samples showed a time-independent newtonian type of flow behavior. The reduction of viscosity with increasing liquid temperature followed an exponential relationship, with the two constants of the equation being a function of the volume percentage of the vegetable oil in the mixture. A single empirical equation was developed for predicting the viscosity of these fuel mixtures under varying temperatures and blend compositions.     

表面活性剂对微生物脱除柴油中有机硫的影响

采用假单胞菌(Pseudomonas delafieldii)菌株R-8和红色红球菌(Rhodococcus erythropolis)菌株N1-36研究了加氢精制柴油脱硫工艺，两株菌脱除柴油中有机硫的活性相近. 添加表面活性剂能提高菌株对柴油的脱硫率；当Tween80存在、搅拌转速为250 r/min时，菌株R-8最高可脱除硫含量<300 mg/L的柴油中72%的有机硫；但当硫含量超过1000 mg/L时，微生物脱硫率极低.     

生物柴油的研究进展

综述了生物柴油的4种制备方法,其中酯交换法以其原料易得、反应时间短、产物易分离等优点被广泛应用于工业生产中.同时分析了生物柴油的优点及在应用中存在的问题,论述了生物柴油在国内外研究现状和发展前景.     

低硫柴油润滑性能改进剂

由于低硫低芳烃柴油的润滑性能下降,会导致发动机的油泵磨损。本文介绍了柴油润滑性的判定方法及国外使用润滑性能改进剂对低硫柴油润滑性能影响的实验数据,建议我国尽早研制出与国外媲美的润滑性能改进剂。     

DZD-1柴油加氢精制催化剂的首次工业应用

概述了DZD-1加氢精制催化剂在大庆石化公司炼油厂加氢精制装置的装填、干燥、预硫化、初期活性稳定、标定及使用情况。在处理焦化柴油以及掺渣比40%的重催柴油等劣质二次加工柴油及混合油时,在操作压力7.0 MPa、空速高达270 h^－1、反应平均温度338 ℃的条件下,表现出较高的加氢精制活性,产品性质大幅度改善,柴油产品质量符合国家优等品质量指标。结果表明,DZD-1加氢精制催化剂具有良好的活性和稳定性,是新一代优良的加氢精制催化剂。     

柴油微乳液的制备及性能研究

采用油水法并结合超声分散法,在30℃下以油酸为表面活性剂、二乙基二乙醇胺为主剂,以甲醇和乙醇作为助剂,采用甲醚和乙醚作为溶剂,制备出最大增溶水量为26.16%的柴油微乳液,对柴油微乳液进行了运动粘度、稳定性、腐蚀性、密度、静置燃烧等理化性能的检测。结果表明,制备出的柴油微乳液具有较低的运动粘度,比0#柴油具有更优异的耐低温性能;室温稳定时间为205~424 d;各样品的腐蚀度均为1A级,不会对内燃机造成腐蚀。该柴油微乳液成本较低,具有广泛的应用前景。