冷冻机油关键技术指标及评价方法综述

传统制冷剂(如氟利昂)会破坏臭氧层和引起温室效应,严重危害到人类赖以生存的生态环境,因而其正全面被臭氧消耗潜能值(ODP)和全球变暖潜能值(GWP)相对较小的、环境友好的新型制冷剂取代。但新型制冷剂存在与传统矿物冷冻机油和烷基苯冷冻机油相溶性不佳等问题,需要研制新型合成冷冻机油(包括聚酯型冷冻机油,聚醚型冷冻机油和聚乙烯醚型冷冻机油)与之配套。由于使用环境的特殊性,冷冻机油与制冷剂的相溶性,冷冻机油/制冷剂混合物与制冷系统材料的相容性,冷冻机油/制冷剂混合物的物性以及冷冻机油/制冷剂混合物的润滑性等是新型冷冻机油的关键技术指标。对冷冻机油的关键技术指标及评价方法进行了讨论。     

HCFCs制冷剂替代对冷冻机油产品需求的影响

文章总结了我国冷冻机油的产品现状、制冷行业的发展方向和冷冻机油的需求情况。目前国内合成型冷冻机油和知名品牌冰箱用低黏度冷冻机油主要为国外进口产品,对国内开发这两种类型冷冻机油的期望与要求非常迫切;国内正在积极研究以R290为制冷剂的压缩机,相关研究机构应积极开发与R290匹配的冷冻机油。     

润滑邮

问:如何选择汽车空调冷冻机油?答:目前市场上车用空调冷冻机油品种繁多,使用的制冷剂R12与R134a并存,因此在加装冷冻机油时必须注意选择,以免加错冷冻机油,造成系统故障。如何选择汽车空调冷冻机油呢?首先要观察系统所用制冷剂,由于制冷剂对冷冻机油的影响甚为关键,因此应首先观察车用空调所使用的是何种制冷剂。R12制冷剂国家虽已禁止使用,但在维修市场,仍有部分制冷剂采用R12。对制冷剂为R12的冷     

新型环保冷冻机油的研制

新型冷冻机油具有与制冷压缩机同寿命等特点，本文采用中压加氢处理组合工艺新技术生产的基础油，复配功能添加剂后，解决了冷冻机油与制冷剂R600a相溶性及与制冷剂共存时的热稳定性、抗磨损等关键问题。所研制的100冷冻机油通过了加西贝拉压缩机台架试验，满足了环保型冷媒R600a冰箱制冷压缩机用冷冻机油对基础油的要求。     

与R134a相容的冷冻机油的研制

研制了适用于R134a制冷剂的季戊四醇酯冷冻机油,该合成冷冻机油加有抗氧剂、抗磨剂和酸捕捉剂,具有倾点低、闪点高、水含量低、与R134a相容性良好、热氧化安定性好和润滑性优良的特点。     

R22型空调压缩机专用冷冻机油的研制

在ISO6743／3B-1988《润滑剂、工业油和有关制品（I级）分类第3B部分：d类（气体和冰箱压缩机）》冷冻机油分类标准中,根据其组成特性及蒸发器操作温度,冷冻机油产品被分为4类,即L—DRA、L—DRB、L—DRC、L—DRD。目前我国GB／T16630一1996《冷冻机油》标准中只有L—DRA和L—DRB这2类冷冻机油,用于全封闭型空调压缩机及热泵的ISOL—DRC冷冻机油尚未形成产品标准．     

替代制冷剂与冷冻机油技术现状及发展浅析

<正>本文对替代制冷剂及与不同制冷剂配套的冷冻机油的现状进行了阐述;介绍了国内冷冻机油生产现状;对国内冷冻机油的发展提出了建议。臭氧层的破坏和全球气候变化是当今世界面临的主要环境问题之一。由于制冷空调热泵行业广泛采用的氟氯烃(CFCs)与氢氟氯烃(HCFCs)类制冷剂对臭氧层有破坏作用以及产生温室效应,使该行     

振动弦法测定制冷剂/冷冻机油混合介质的黏度

运动黏度是润滑油关键的技术指标之一,在一定程度上可以反映润滑油的润滑性,但仅依据冷冻机油的运动黏度却无法准确判断冷冻机的润滑状况。因为在冷冻机中冷冻机油与制冷剂相互溶解形成制冷剂/冷冻机油混合介质,冷冻机油被稀释,运动黏度显著下降,润滑性能也会随着下降。为了预测冷冻机油的润滑性,测定实际工况条件下制冷剂/冷冻机油混合介质的运动黏度十分必要。为此开发了测定制冷剂/冷冻机油混合介质运动黏度的振动弦法,该方法的相对偏差在±3.0%以内,可为预测冷冻机油在冷冻机中的润滑性以及为研制新型的冷冻机油提供帮助。(图3表2参考文献3)     

冷冻机油对R600a型冰箱压缩机制冷性能的影响

采用GB 9098-1996压缩机制冷性能评定方法,对不同类型、不同黏度等级冷冻机油与R600a型冰箱压缩机制冷性能之间的关系进行分析.结果表明:适宜的低黏度型冷冻机油有助于提高R600a型冰箱压缩机的制冷性能;制冷量与制冷系数随冷冻机油黏度变化趋势曲线的交叉点处为压缩机发挥最佳制冷性能的控制点;冷冻机油对R600a型...     

4522合成冷冻机油在丙烷制冷系统上的应用

为了替代进口冷冻机油,对4522合成冷冻机油的性能及在炼油连续重整装置丙烷制冷系统上的应用情况进行了考察。分析表明,4522合成冷冻机油的性能达到了进口冷冻机油的水平。在近1年的实际应用中,丙烷制冷系统的工作参数正常,4522合成冷冻机油的监测数据在指标范围内,还可以继续使用。说明了4522合成冷冻机油能够满足炼油连续重整装置丙烷制冷系统的润滑要求,可以代替进口冷冻机油使用,实现了丙烷制冷系统冷机油的国产化。     

用于R134a和R22的合成冷冻机油研究

根据制冷系统对冷冻机油的性能要求、合成冷冻机油性能特点,参照美国海军商业规范提出研制油的主要技术指标,制备一种以改性聚醚作基础油的合成冷冻机油。对研制油的理化性质、与制冷剂R134a和R22的互溶性、化学稳定性（密封管试验）、稳定性（菲利浦试验）、电绝缘性、润滑性等进行评价,并在斜盘式汽车空调压缩机上与R134a配套使用。评价和应用结果表明,研制的合成冷冻机油满足制定的技术指标要求,并可以用于R134a和R22制冷系统。     

矿油型螺杆式制冷机组通用冷冻机油的研制

对比分析了以R717(氨)及R22(一氯二氟甲烷)为冷媒的螺杆式制冷机组用油特点,选取合理的环烷基馏分及加工工艺,配合适宜的添加剂方案,使产品具有良好的抗磨损性能、氧化安定性及与制冷剂共存时的化学稳定性,研制产品通过了两种制冷机组的使用试验。     

4522合成冷冻机油在MYCOM冷冻机组上的应用

介绍了4522合成冷冻机油在MYCOM冷冻机组上的应用情况，4522合成冷冻机油可以替代进口油用于MYCOM冷冻机组的润滑。     

合成润滑油在冷冻系统中的应用

综述了聚α-烯烃、烷基苯、聚醚、双酯、新戊基多元醇酯、硅酸酯、氟油等合成润滑油在冷冻系统中的应用。     

采用加氢工艺研制56号冷冻机油

以克拉玛依环烷基原油减二线馏分油为原料,采用国产加氢精制、临氢降凝催化剂,在100 mL小型加氢实验装置上,经过工艺条件的优化,评选出适宜的工艺条件,研制出可满足56号冷冻机油产品要求的基础油,通过加入适宜的添加剂配方,可生产出市场需求的56号冷冻机油产品。     

Variations in wetting behavior of mixed-wet cores resulting from probe oil solvency and exposure to synthetic oil-based mud emulsifiers

Mixed wettability (MXW) results from adsorption from crude oil on rock surface which is not overlain by bulk water. Crude oil/brine/rock interactions and their effect on oil recovery are often investigated after replacing the crude oil with a mineral oil. If crude oil is displaced directly by mineral oil, extreme wettability alteration, referred to as MXW-DF (direct flood), is observed. Less change is observed if an intermediate solvent, such as decalin, is used to avoid destabilization of asphaltenes contained in the crude oil; wettability conditions attained by this treatment are referred to as MXW-F (film). The oil used in a displacement test is referred to as the probe oil, the most common choice being either crude oil or mineral oil. There is strong practical interest in developing MXW-F cores that have wetting properties that are comparable to wettability at reservoir conditions. The main objective of this work is to compare the effect of probe oil solvency, characterized by refractive index, on wetting behavior, characterized by spontaneous imbibition, with MXW wettability given by the parent crude oil. The tested probe oils included mineral oils, alkanes, decalin, toluene, alpha-methylnaphthalene (AMN), crude oils and modified crude oils with both increased and reduced solvency, and base oils and solutions of emulsifiers used in synthetic oil-based mud (SBM) formulations. Wettability established by direct displacement of crude oil with an alkane (MXW-DF) showed systematic increase in water wetness with increase in solvency of the probe oil. Other approaches to tuning MXW-F wettability states by choice of probe oil are also presented. Base oils used in the formulation of SBM had essentially no effect on the imbibition behavior of MXW-F, whereas exposure of MXW-F cores to two kinds of emulsifier resulted in persistently suppressed imbibition for a wide range of probe oils.     

国产油在MYCOM丙烷冷冻机中的应用实践

根据天然气处理装置中MYCOM丙烷辅助制冷系统的特点,依据冷冻机油的选用原则,选取了某国产油为备选进口替代油品。通过红外谱图、常规理化指标、润滑性能、热氧化安定性、混油试验的评价,确认了该国产冷冻机油可作为进口油的代用油品的可行性。从油品监测、运行参数监测、设备振动趋势监测的结果来看,该国产冷冻机油的应用完全满足MYCOM丙烷冷冻机的运行要求,可替代进口油用于MYCOM丙烷冷冻机。     

碳氢化合物在制冷工质替代过程中的应用

氟利昂类物质由于会破坏臭氧层并产生温室效应而被限制使用，并规定了禁用年限，因而寻找一种对环境不产生危害的环保制冷剂就成为了制冷行业的当务之急。碳氢化合物类制冷剂如丙烷（HC290）、丁烷（HC600）、异丁烷（HC600a）等ODP值为零，GWP值很小，具有很好的热力学特性，且为天然物质，因此是一种很好的氯氟烃制冷剂替代物。为此，分析了常用碳氢化合物制冷工质的物性、热力学特性、循环特性，并与二氟一氯甲烷（CFC12）、二氟二氯甲烷（HCFC22）和四氟乙烷（HFC134a）等氯氟烃制冷工质作了对比分析，总结了它们在制冷空调等领域的应用和研究现状，并对其可燃性和在制冷行业的应用前景进行了分析。     

Stability of Water-in-Crude Oil Emulsions: Effect of Oil Aromaticity,Resins to Asphaltene Ratio,and pH of Water

Abstract

The formation of tight water-in-oil emulsions during production and transport of crude oils is a great problem challenging the petroleum industry. Tremendous research works are directed to understanding the mechanism of formation, stabilization, and controlling of oil field emulsions. This article presents experimental results of some of the factors controlling the formation and stabilization of water-in-crude oil emulsions. In this study, asphaltenes and resins separated from emulsion samples collected from Burgan oil field in Kuwait have been used to study emulsion stability. Model oils of resin to asphaltene ratio of 5:1 and toluene-heptane mixtures have been used to study the effect of oil aromaticity on emulsion stability. Results indicate that at low toluene content (below 20%) or high content (above 40%) less stable emulsions are formed. At a threshold value of 30% toluene, a very tight model oil emulsion is formed. The effect of resins to asphaltene (R/A) ratio on stability of model oil has also been investigated. Results reported in this paper show that as the R/A increases the emulsions become less stable. The effect of pH on stability of model oil emulsion made of 50/50 heptane-toluene mixture having R/A ratio of 5:1 have been studied. Experimental results revealed that as the pH of the aqueous phase of model oil increased from 2 to 10, the emulsion became less stable. At high pH, the asphaltene particles are subjected to complete ionization leading to destruction of the water-oil interface and eventually breakdown of the emulsion.