实沸点蒸馏过程中的影响因素

实沸点蒸馏时原油评价的首要工作,实验过程中各馏分的精确分离是准确评价原油性质的基础,通过对蒸馏过程中各种影响因素的分析探讨,减小蒸馏误差,提高实沸点蒸馏数据的准确性。     

超声波对混合原油稳定性的影响

由于原料的限制,我国炼油企业普遍采取原油混炼的措施。不同性质原油混合时,出现絮凝现象,给原油储运和加工带来影响,本文开展超声波对混合原油稳定性的研究,实验结果表明,混合原油经超声波处理能提高其稳定性。     

不同类型添加剂强化原油蒸馏过程及机理

引　言由于石油中的组分不是简单地以分子形式混合形成的真溶液 ,因此在原油蒸馏时一部分烃类分子难以转入气相 ,导致原油的拔出率降低 .据文献报道[1] ,在常压渣油中约有 5 %的沸点低于 35 0℃的轻组分不能通过蒸馏作用拔出 .由此可见 ,对原油蒸馏装置尚有较大潜力可挖 .目前 ,普遍认为用加入活性添加剂以强化原油蒸馏过程、提高其拔出率是非常有效而又简单易行的方法 .国内外研究人员所采用的添加剂 ,按其类型主要有芳烃浓缩油[2 ] 、表面活性剂[3] 和复合活化剂[4 ] (即前两类添加剂复配 ) .根据石油体系的特点 ,本文又研究开发出一类添…     

强化蒸馏助剂的应用研究

介绍了在原油蒸馏中通过添加强化蒸馏助剂提高拨出率的理论、实践和强化蒸馏助剂的作用机理。实验表明,强化蒸馏助剂可提高西安石油化工厂沥青油和陕北原油的轻质油收率;添加助剂质量分数为100×10^－6时可提高收率1.3个百分点,具有技术经济可行性。     

提高油水自动分离效率的方法

轻质油当被蒸馏出来之后,又再次被混合在原油当中时,分离不好的轻质油回掺将对整个系统的密度及含水将会造成一定的影响,有的时候甚至会影响原油外输产量,因此如何提高油水自动分离效率,找出合理的方法,有效控制轻质油掺入量成为可能。     

延长混合原油综合评价与加工方案的研究

对延长混合原油进行了综合评价,分析了原油和各个馏分油的性质。实验结果表明,该混合原油具有密度小、凝点低、硫含量低的特点,属于低硫石蜡-中间基原油。实沸点蒸馏及窄馏分性质分析表明,该混合原油初馏点<40℃,小于200℃直馏汽油收率22.29%,140~240℃喷气燃料馏分收率9.96%,200~350℃柴油馏分收率28.43%,350℃前馏分油收率合计50.72%,且混合原油灰分含量低,重金属含量不高,氮含量较低,适宜生产燃料和润滑油型炼厂加工。     

300万吨年大庆原油常压塔设计

石油炼厂中的第一个生产装置一般都是蒸馏装置,人们通过蒸馏将石油分割成相应的直馏汽油、化工原料、轻柴油或重柴油馏分及其他馏分。所谓原油的一次加工,就是指原油蒸馏而言。借助于蒸馏,我们可以将原油分割成各种半成品馏分油,也可将原油分割成一些二次重整加工的原料。在一些二次加工的装置中,蒸馏过程也是不可缺少的组成部分。蒸馏过程是炼厂中一种最基本的,也是最重要的一种工艺。蒸馏过程和设备的选型设计是否合理,操作是否良好,对炼厂生产影响较大。因此,必须通彻了解蒸馏工艺的本质规律,掌握其影响因素和设计方法,对炼油工艺的专业人员来说是相当重要的。     

膜蒸馏技术用于高盐污水回用研究

将膜蒸馏技术应用到高盐污水处理回用领域,以石化反渗透浓水为实验体系,采用几种现有的疏水膜材料,研究了不同类型的各种材质的膜对膜蒸馏过程通量及产水水质的影响。在此基础上,采用酸碱清洗液对膜蒸馏的膜污染进行了清洗,并进行了清洗效果的表征。     

原油加剂强化蒸馏的研究进展

为了提高轻质油收率,解决石油市场的供需矛盾,人们提出并开发了原油强化蒸馏技术。为此,介绍了加剂强化蒸馏作用机理,归纳了活化剂的设计原则和主要成分,通过对原油强化蒸馏的实验研究和工业应用的总结,指出了其目前存在的问题,并对原油强化蒸馏今后的发展提出一些建议。     

水泥与减水剂相容性的研究

减水剂与水泥之间的相容性是现代混凝土生产与施工所必须考虑的问题,也是水泥生产企业应该关注的问题。本文研究了两种高效减水剂对不同企业生产的水泥的相容性,研究了掺不同混合材时水泥与减水剂的相容性。结果表明,同一种水泥与不同减水剂之间的相容性不一样;同一种减水剂与不同厂家的水泥之间的相容性也不一样;各种混合材对减水剂的适应性也有较大的差距。分析了影响水泥与高效减水剂相容性的因素。     

The optimization and prediction of properties for crude oil blending

Research into the properties of mixed crude oils has been the most important research for refineries and oil transportation. Because the desirable nature of mixed crude oils is a powerful guarantee for normal operations and corporate earnings. In this paper, the optimization and prediction model for Shanbei crude oil blending is established. The objectives were to improve the total yield of fractions and the compatibility and to reduce the viscosity of the mixed crude oils. After solving the model, two applicable proportions for mixed crude oils were given. With these proportions, two samples of mixed oils were prepared and distilled. The test results showed that the model was valid. The study of the viscosity and compatibility index was introduced to the optimization model because forecasting those properties in mixed crude oils has a certain significance.     

Removal of chlorinated pesticides from crude vegetable oils by simulated commercial processing procedures

Crude soybean and cottonseed oil were processed using simulated commercial processing procedures to determine if oil processing would remove chlorinated pesticide contaminants of either natural or spiked origin. Two crude oil lots were spiked with endrin, DDT, DDE, aldrin, dieldrin, heptachlor and heptachlor epoxide before processing. Representative samples of crude oil and products following each processing step were analyzed for pesticide contamination. Results indicated that alkali-refining or subsequent bleaching did not reduce chlorinated pesticide contamination. Hydrogenation prior to deodorization reduced endrin contamination. Deodorization, with or without hydrogenation, eliminated chlorinated pesticides. The results of this study indicate that normal commercial processing of crude vegetable oils for human consumption effectively removes any chlorinated pesticides which may be present in crude oils. It is hypothesized that chlorinated pesticide removal is achieved by volatilization during deodroization, which is supported by known volatilization characteristics, similarity of behavior in pesticides studied, and absence of the pesticide or its conversion products in the finished oils, or both.     

六种国外原油品质评价与加工方案可行性浅析

将来自不同国家和地区的六种国外原油分别进行实沸点蒸馏。对这些原油的一般性质、直馏产品收率、各馏分油的性质进行了对比与分析，以及原油加工方案的可行性进行了初步探讨，为优化加工方案提供参考。     

Thermal degradation of FA and catfish and menhaden oils at different refining steps

The thermal degradation (weight loss) of individual FA and of catfish and menhaden oils collected from different refining steps was investigated by thermogravimetric analysis. The heat resistance of FA was partially dependent on chain length and degree of unsaturation. The weight loss of catfish and menhaden oils increased with increased heating temperatures, regardless of the oil refining process. All oil samples (except crude catfish oil) were decomposed after the heating temperature reached 550°C. Based on the thermogravimetric curves, the following thermal stability sequence at different refining steps for both catfish and menhaden oils was proposed: crude > degummed > neutralized > bleached > deodorized oils.     

Studies on the pigments of some citrus,prune and cucurbit seed oils when processed with or without cottonseed oil

Pigments of citrus, prune and cucurbit fruit seed oils were studied spectrophotometrically. The citrus fruits used were: orange (O), mandarin (M), bitter orange (BO) and lemon (L). The prunes used were apricot (A), peach (P) and plum (PL); while melon (M), watermelon (WM) and Winter squash (S) were the cucurbits. Absorption spectra and Lovibond color were studied for crude, refined and bleached oils. Cottonseed oil (CSO) was mixed with some of the previous oils in the crude state, then refined and bleached. Absorption spectra of the crude fruit seed oils revealed carotenoid pigments at 400, 425, 455 and 480 nm, chlorophyll at 610 and 670 nm and unknown pigments at 525, 570 and 595 nm. Refining did not remove these pigments, whereas bleaching eliminated them completely. In oil mixtures of CSO+A, CSO+M and CSO+S, interference occurred between gossypol ‘360 nm’ from CSO and the pigments of A, M and S seed oils. Refining the oil mixtures removed gossypol, but its effect on carotenoids, chlorophyll and unknown pigments was limited. Bleaching completely removed all these residual pigments. Lovibond color for all bleached oils was very low (0.2–2 yellow). The refined oils, except those containing Winter squash seed oil, were found to have an acceptable color (0.8–15 yellow). Results of the proposed process reveals the possibility of mixing crude edible oil with crude fruit seed oils, then processing the oil mixture by the conventional methods of refining and bleaching.     

Colored components of processed palm oil

The compounds responsible for the colors of palm oils at various stages of processing have been isolated by gel permeation chro matography. The isolated colored compounds have been characterized by visible spectroscopy and, in some cases, further fractionated by high performance liquid chromatography. All palm oils studied contained colored compounds of both higher and lower molecular weight than triglycerides. Oils at different stages of processing contained different proportions of these high and low molecular weight, colored compounds. While the color of crude palm oils was primarily due to the low molecular weight carotenoids, the color of finished oils was due to compounds other than carotenoids. High molecular weight compounds were significant, sometimes predominant, contributors to finished oil colors. These results demonstrate the importance of high molecular weight, colored compounds to the color of finished palm oils. Further, these results suggest that the difficulties associated with decolorization of certain crude palm oils may be due either to the presence of high molecular weight, colored compounds or to the presence of precursors capable of generating these compounds during the decolorization process.     

A comparison of wesson loss and cup refining loss analyses of crude cottonseed and soybean oils

Wesson loss and cup refining loss were determined on 100 samples of crude cottonseed and soybean oils produced in different sections of the country. The Wesson method gave more reproducible results than the cup method. Wesson loss results were found to be closely indicative of the total neutral oil content of crude oils. The average ratio of cup loss to Wesson loss was 2.3 for crude cottonseed oil and 1.7 for crude soybean oil. The ratio varied considerably for individual crude oils of a given kind, or type within each kind, or a local producing section. Therefore, no real useful correlation between the results of the two methods was found to exist.     

Wax composition of sunflower seed oils

Waxes are natural components of sunflower oils, consisting mainly of esters of FA with fatty alcohols, that are partially removed in the winterization process during oil refining. The wax composition of sunflower seed as well as the influence of processing on the oil wax concentration was studied using capillary GLC. Sunflower oils obtained by solvent extraction from whole seed, dehulled seed, and seed hulls were analyzed and compared with commercial crude and refined oils. The main components of crude sunflower oil waxes were esters having carbon atom numbers between 36 and 48, with a high concentration in the C₄₀−C₄₂ fraction. Extracted oils showed higher concentrations of waxes than those obtained by pressing, especially in the higher M.W. fraction, but the wax content was not affected significantly by water degumming. The hull contribution to the sunflower oil wax content was higher than 40 wt%, resulting in 75 wt % in the crystallized fraction. The oil wax content could be reduced appreciably by hexane washing or partial dehulling of the seed. Waxes in dewaxed and refined sunflower oils were mainly constituted by esters containing fewer than 42 carbon atoms, indicating that these were mostly soluble and remained in the oil after processing.     

Polycyclic aromatic hydrocarbons in crude and deodorized vegetable oils

The efficiency of the refining process in removing polycyclic aromatic hydrocarbons (PAH) from crude vegetable oils was studied. Samples of the crude oils (coconut, soybean and rapeseed oils) and the corresponding refined, deodorized oil were taken on-line in three Swedish oil refineries and margarine manufacturing plants and analyzed for 20 different PAHs. Of the crude oils, coconut oil had by far the highest PAH levels. However, the PAH levels in the refined coconut oils were very low. This shows that the activated charcoal treatment used for removing PAHs from coconut oil achieves the desired effect. The crude soybean and rapeseed oils contained relatively low, but varying, amounts of PAH. At present these oils are not purified by activated charcoal. Nevertheless, the PAH levels in the refined oils were considerably lower than those in the corresponding crude oils. This probably is due to evaporation of PAH in the deodorization process, where steam is passed through the hot oil under high vacuum. However, deodorization has only a marginal effect on the high molecular PAHs, of which several are classified as carcinogens.     

Oxidation and quality of soybean oil: A preliminary study of the anisidine test

The anisidine test, a measure of secondary oxidation products in glyceride oils, was applied to a number of soybean salad oils processed from sound and damaged soybeans. A highly significant correlation (−0.68) was found between the anisidine values of salad oils from sound soybeans and their flavor scores. Multiple correlations between flavor scores, anisidine, and peroxide values yielded a correlation of 0.81 and provided a method for predicting the initial flavor scores of sound soybean salad oils. Similar data for oils from damaged beans gave a highly significant, but lower, correlation (−0.65). Comparative studies indicated that sound crude oils usually contain lower levels of oxidation products than damaged crude. Oxidation in both sound and damaged crudes increased roughly in proportion to iron content. Reproducibility of the test and the effects of hydrogenation, accelerated storage, and fluorescent light on anisidine values were studied. Analysis of damaged oils before and after deodorization showed that little, if any, reduction of anisidine value occurred. Deodorization of sound oils, however, lowered anisidine values. In comparison with damaged oils, the anisidine values of sound oils were lower at comparable stages of processing. The poor quality of damaged soybean oil was substantiated by organoleptic evaluations. Flavor scores of oils given special processing treatments increased as anisidine values decreased.