差示扫描量热法测定费托蜡滴熔点的研究

采用DSC法对费托蜡滴熔点进行测定,研究了升降温速率、升温次数、起始和终止温度、氮气吹扫气流量、平衡时间、试样质量等对测试结果的影响,确定了DSC法测定滴熔点的适宜条件,考察了DSC法测定费托蜡滴熔点的重复性、准确性和再现性。实验结果表明,DSC法测定费托蜡滴熔点的适宜条件为：第一次升降温速率20℃/min、第二次升温速率5℃/min、熔融过程的起始温度为室温、终止温度高于预估滴熔点20～30℃、取样质量5～10 mg、氮气吹扫气流量10～50 mL/min、熔融与结晶过程转变平衡时间2 min。DSC法测定费托蜡滴熔点操作简单、试样用量少、检测速率快、重复性和再现性良好、测试结果准确,可作为传统方法的替代手段。     

采用DSC法测定原油的比热容

采用DSC法测定了原油的比热容,以蒸馏水为标准物质,考察了升温速率、试样用量和工作气流量等因素对测定结果相对偏差的影响,得到了较佳的实验条件。实验结果表明,将实验误差控制在最小值的实验条件为:试样皿和参比皿的质量偏差控制在±0.1 mg内、试样用量5 mg左右、工作气流量20 mL/min、升温速率2℃/min。通过将测试的原始数据进行修正,可进一步降低DSC法的系统误差,最终可将系统误差降至2%以内,提高了DSC法测定原油的比热容的精确度。与绝热量热法相比,采用DSC法测定原油的比热容,操作简单,可行性强,可满足实验测定要求。     

DSC法测定汽油馏分的低温比热容

用差示扫描量热计（ＤＳＣ）测定５个汽油馏分（沸点小于２００℃）在２４３～２９９Ｋ范围内的比热容,测量误差在±２％以内。比较了比热容实测值与国外常用计算方法的预测结果。还由比热实验值计算低温焓,它们与铜量热计测得的高温焓间具有较好的一致性     

干酪根的差示扫描量热法(DSC)的研究

作者以抚顺、茂名、黄县油页岩干酪根和黄县褐煤有机质为试样,采用差示扫描量热法(DSC).对干酪根的热演化进行研究,并根据干酪根结构参数的变化,讨论其母质类型及油气生成潜力.      

石蜡微胶囊中脲醛树脂壁材渗透性的研究

利用差示扫描量热法研究了石蜡微胶囊中脲醛树脂壁材对水及甲苯的渗透性 ,结果表明 ,水不能透过脲醛树脂壁材 ,而甲苯则易透过脲醛树脂壁材。因此 ,该石蜡微胶囊不能用于芳香族溶剂存在的场合。     

对差示扫描量热法测定原油中蜡的质量分数的思考

SY/T 0545存在着原油析蜡热焓定义不准确,热焓图谱示意不当,热焓积分面积基线等问题。用差示扫描量热法测定原油中蜡的质量分数,应该按不同区块的原油选择不同的热焓积分温度区间,用差示扫描量热法检测区块标准原油的析蜡热焓,用SY/T 0537—2008检测该标准原油中蜡的质量分数。这两个数值参与计算本区块其他待测油样的蜡含量,其结果会更准确,与传统方法更具可比性。     

利用发汗工艺制取低熔点半精炼石蜡

介绍了应用石蜡发汗工艺以酮苯脱蜡装置副产的蜡膏为原料生产低熔点半精炼石蜡的过程。指出采用二次发汗的生产方案,得到的成品质量指标较为接近要求,熔点降至48.2℃,但含油量高于1.5%（质量分数,以下同）;而采取二次发汗、再结合分段切割措施,生产出的成品熔点为48.2℃、含油量为0.82%,适用于调和美容蜡等特种蜡的低熔点半精炼产品。     

酮苯脱蜡装置蜡下油中固态烃的组成研究

以中国石化高桥分公司3号酮苯脱蜡装置加工的减二线和减五线蜡下油为原料,分别采用低温发汗和酮苯脱蜡脱油试验的方法,从轻馏分（减二线）的蜡下油中,得到了固态烃化学组成以正构烷烃为主的低熔点石蜡,从重馏分（减五线）的蜡下油中,得到了固态烃化学组成以大量的环烷烃和异构烷烃为主的低熔点微晶蜡。对低熔点石蜡分析结果表明,该石蜡具有吸热温度范围窄、吸热量高、相变温度和峰顶温度适中等特点,可以开发为相变石蜡产品。同时,低熔点微晶蜡的化学组成较好地解释了一直以来工业生产中一段脱蜡二段脱油工艺"对轻馏分效果好,而对重馏分效果差"的现象,为今后生产高熔点、低含油量石蜡方案提供了依据。     

Correlations Between the Pour Point/Gel Point and the Amount of Precipitated Wax for Waxy Crudes

The amount of precipitated wax is one of the key factors that governs the flow properties of waxy crudes. Experimental results of 24 crudes have shown that approximately 2 wt% precipitated wax is sufficient to cause a virgin waxy crude gelling. Accordingly, a correlation between the pour point and the temperature at which 2 wt% of wax has precipitated out from a crude oil; i.e., T_c(2 wt%), and a correlation between the gel point and T_c(2 wt%) have been developed. The proposed correlation of the pour point is in accordance with the correlation developed by Letoffe et al. (1995) on the basis of 14 crudes from eight countries. The development of the gel point correlation and further verification of the pour point correlation indicate that there is a relationship between the gelling of virgin waxy crudes and the amount of precipitated wax. According to these correlations and the amount of precipitated wax, which can be determined only with a little sample by thermodynamic models or Differential Scanning Calorimetry (DSC) experiment, the gel point and pour point of virgin waxy crude can be predicted even if the oil sample is very limited. Heat treatment and chemical treatment can greatly improve flow behavior of waxy crudes, and more precipitated wax is present when the beneficiated (thermally beneficiated or PPD-beneficiated) crude oils gel. Experimental results showed that approximately two or three times the amount of precipitated wax presents at the gelling temperature when the oils were in their beneficiated (thermally beneficiated or PPD-beneficiated) conditions.     

Correlations Between the Pour Point/Gel Point and the Amount of Precipitated Wax for Waxy Crudes

Abstract:

The amount of precipitated wax is one of the key factors that governs the flow properties of waxy crudes. Experimental results of 24 crudes have shown that approximately 2 wt% precipitated wax is sufficient to cause a virgin waxy crude gelling. Accordingly, a correlation between the pour point and the temperature at which 2 wt% of wax has precipitated out from a crude oil; i.e., T _c (2 wt%), and a correlation between the gel point and T _c (2 wt%) have been developed. The proposed correlation of the pour point is in accordance with the correlation developed by Letoffe et al. (1995) Letoffe, J. M., Claudy, P., Kok, M. V., Garcin, M. and Vollet, J. L. 1995. Fuel, 74(6): 810–817. [CSA][CROSSREF][Crossref] , [Google Scholar] on the basis of 14 crudes from eight countries. The development of the gel point correlation and further verification of the pour point correlation indicate that there is a relationship between the gelling of virgin waxy crudes and the amount of precipitated wax. According to these correlations and the amount of precipitated wax, which can be determined only with a little sample by thermodynamic models or Differential Scanning Calorimetry (DSC) experiment, the gel point and pour point of virgin waxy crude can be predicted even if the oil sample is very limited. Heat treatment and chemical treatment can greatly improve flow behavior of waxy crudes, and more precipitated wax is present when the beneficiated (thermally beneficiated or PPD-beneficiated) crude oils gel. Experimental results showed that approximately two or three times the amount of precipitated wax presents at the gelling temperature when the oils were in their beneficiated (thermally beneficiated or PPD-beneficiated) conditions.     

Physical Properties of Petroleum Waxes. I. Effect of Oil Content

The effect of oil content on the physical properties of five microcrystalline waxes having widely different oil content have been investigated. It has been observed that the physical properties are affected to a great extent by the variation in oil content. Oil content has a profound effect on viscosity, hardness, and crystallinity of waxes. The effect is not so profound in the case of melting point.     

Physical Properties of Petroleum Waxes. I. Effect of Oil Content

Abstract

The effect of oil content on the physical properties of five microcrystalline waxes having widely different oil content have been investigated. It has been observed that the physical properties are affected to a great extent by the variation in oil content. Oil content has a profound effect on viscosity, hardness, and crystallinity of waxes. The effect is not so profound in the case of melting point.     

Investigation on Microcrystalline Wax Doped Asphalts by Temperature Control Mode of Atomic Force Microscopy

Because of its economical and environmentally friendly characteristics, the warm mix asphalt(WMA) is widely used in pavement engineering. However, the lack of microscopic study of WMA brings difficulties in understanding of its mechanical behavior and mechanisms at macroscopic scale which finally hinders the enhancement of WMA's performance. Therefore, this article aims to use atomic force microscopy(AFM), a promising microscopic technique, to investigate the effects of wax-based warm mix agents on asphalt microstructures and micromechanical properties at different temperatures. For simplicity's sake, microcrystalline waxes are selected as an alternative of these wax-based additives. It is shown that the sample preparation method has a vital impact on the morphology of asphalt samples. The effects of microcrystalline wax on asphalt's mechanical properties can be well captured by AFM tests. Results show that the blending of #70, #80 and #90 microcrystalline waxes lowers the modulus(20—60 MPa) of Pen70 asphalt at 25 ℃ while increasing its adhesion force(5—20 n N). The results of this study may shed some light on the comprehension of the effects of wax-based additives on asphalt materials at macroscopic level which can help estimate and predict its actual performance.     

辽化蜡油降凝剂的合成

以反丁烯二酸、14醇与26醇的混合物(混合醇)、醋酸乙烯酯为原料,采用"先酯化后聚合"的方法,合成了一种适用于辽化蜡油的降凝剂——反丁烯二酸混合醇酯-醋酸乙烯酯(简称酯-酯)共聚物。利用FTIR,1H NMR,GPC等方法分析了该共聚物的结构。通过单因素及正交实验确定了合成该共聚物适宜的酯化条件和聚合条件分别为:n(反丁烯二酸)∶n(混合醇)=1∶1、酯化溶剂甲苯的用量25.0%(w)(基于反应体系质量,下同)、对甲苯磺酸催化剂用量1.5%(w)、酯化时间3.0 h;n(反丁烯二酸混合醇酯)∶n(醋酸乙烯酯)=1∶1.25、聚合溶剂甲苯的用量50.0%(w)、过氧化苯甲酰引发剂用量1.75%(w)、聚合温度85℃、聚合时间3.5 h。酯-酯共聚物用作辽化蜡油降凝剂时,适宜的降凝条件为:共聚物用量0.4%(w)(基于辽化蜡油的质量)、热处理温度70℃、热处理时间30 min。     

高含蜡柴油用PCH降凝剂应用效果评价

简述了国内外降凝剂发展概况,分析了南阳石蜡精细化工厂生产的柴油对目前国内外降凝剂感受性差的主要原因,选择PCH降凝剂作为高含蜡柴油降凝剂。实验及工业应用表明,PCH降凝剂能有效地降低该厂柴油的冷滤点,当加入量为0．05％,调合柴油的冷滤点下降4℃,满足了油品的使用标准;并使柴油收率提高2％,经济效益明显。PCH降凝剂与现行国内外降凝剂产品相比,具有独特效果,对高含蜡柴油具有极好的推广应用价值。     

Wax Deposition in Flow Lines Under Dynamic Conditions

The wax deposition in the tubing, pipeline, and surface flow line is the major problem in the oil fields. It generates additional pressure drop and causes fauling and ultimately increases the operating cost during production, transportation, and handling of waxy crude oil. In this work, attempts were made to study the wax deposition in the flow lines due to Indian crude oil under dynamic condition. The experimental work was carried out for neat crude oil and pour point depressants treated crude oil at different ambient/surface temperature and pumping/reservoir temperature. It was observed that temperature has significant effect on the wax deposition of the crude oils. From these studies, ideal temperature of crude oil to pump in the pipeline or flow line was determined. The present investigations also furnishes that the selected pour point depressant in this work decreases the wax deposition significantly and may be used for controlling the wax deposition problems in case of Indian crude oil.     

新型蜡晶分散助剂的制备及柴油降凝研究

以乙二胺、丙烯酸甲酯、丙烯酸高碳酯为原料，乙醇钠为催化剂，通过Michael加成和酰胺化反应，合成了一种含有长链烷基和多氨基、酰胺基极性官能团的柴油蜡晶分散助剂。红外光谱检测表明产物与理论设计相符。降凝实验表明，单独添加1000μg/g蜡晶分散助剂时，冷滤点降低2—4℃；与降凝剂T1804复配时，凝点最大降低15℃，冷滤点最大降低9℃；与自制降凝剂复配后，凝点最大降低11℃，冷滤点最大降低7℃。说明制备的蜡晶分散助剂与降凝剂有良好的协同效应。