原油组分低温氧化机理和反应活性实验研究

分析了原油和原油组分低温氧化的机理,通过实验进行了不同油品低温氧化反应,考察了氧化反应前后原油族组成的变化,并研究了单组分(正十六烷、蜡、蒽、沥青质)在不同温度下的低温氧化速率和反应活性,得出了不同原油组分的低温氧化反应的活化能。结果表明,稠油较轻质油有更好的氧化反应活性,在较低温度下稠油更容易被氧化,原油中不同组分及含量是影响氧化反应活性和氧化反应速率的重要因素,重组分的沥青质和长链烷烃在低温下(70~90℃)氧化活性较高,正十六烷和蒽反应活性较之重组分低。揭示了原油组分低温氧化反应机理以及不同组分氧化反应活性的区别,为油田注空气工艺方案设计提供基础。     

低温氧化对原油组成的影响

通过空气与原油在油藏温度和一定压力下低温氧化过程的模拟实验,对反应前后气体与原油的组成进行分析.结果表明,实验条件下低温氧化反应后原油芳烃含量减少,胶质含量增加,饱和烃含量和沥青含量基本不变,正构烷烃轻重组分比增加;原油黏度有所增加.     

催化剂对原油低温氧化的影响

在模拟地下油藏条件下,加入催化剂进行重质原油低温氧化反应实验研究,对氧化前后的气体组成及含量变化、原油组分变化进行分析.结果表明,加入催化剂后在150℃以下显著提高了原油低温氧化效率,且与未加入催化剂的低温氧化反应对比,加入催化剂后氧气消耗更多,生成二氧化碳含量增加.200℃以下原油重质组分含量下降,饱和烃、芳香烃轻质组分含量增加.     

油藏矿物和化学剂强化稠油水热裂解降黏研究

采用大庆、辽河两种稠油,研究了油藏矿物、硫酸镍催化剂以及四氢萘供氢剂对其水热裂解反应的影响。结果表明,与单纯水热裂解相比,油藏矿物的加入能使两种稠油的平均相对分子质量减小,饱和烃和芳香烃组分含量增加,胶质和沥青质组分含量减少,稠油的降黏率分别从7.41%和12.95%增加到16.05%和25.29%,油藏矿物对稠油水热裂解反应具有催化作用;将硫酸镍和四氢萘加入反应体系后,稠油平均相对分子质量进一步降低,族组分中饱和烃和芳香烃进一步增加,胶质和沥青质组分进一步减少,稠油黏度明显降低,降黏率可高达84.39%。     

压力对塔里木原油四组分热解性能的影响

压力对深层油藏原油热化学过程的影响尚存在较大争议,为研究其在油藏原油热解成气过程中的作用机理,我们在450℃、5~40 MPa压力下对塔里木原油四组分(饱和分、芳香分、胶质和沥青质)进行了封闭体系的热解实验,通过气相色谱(GC)和气相色谱/质谱(GC/MS)分别对原油四组分热解反应的气体产物及饱和分热解过程的液态产物进行了分析。结果表明,在450℃、24 h及不同压力下,沥青质热解产气率高于胶质、芳香分和饱和分;四组分的气相热解产物中,C1的产率明显高于C2~C5组分。增大压力抑制沥青质、胶质及芳香分的热解产气过程而促进饱和分的热解产气过程。随压力的增大,饱和分热解的液态产物的主峰组分碳数先减小,再增大。压力低于20 MPa时,饱和分热解过程中以裂解反应为主;高于30 MPa时,增大压力有利于缩合反应。研究结果可为认识深层油藏原油的稳定程度及天然气的成因提供一定的理论参考。     

自由基引发剂强化稠油催化水热裂解降黏行为

本文考察了自由基引发剂对胜利油田单56区块稠油样品催化水热裂解反应过程的协同强化作用.在反应温度为220℃,添加0.2 wt%的引发剂——过氧化二叔丁基,使水热裂解后的降黏率由不加引发剂时的61.4%升高到72.7%.此外,在引发剂存在、150℃条件下,降黏率可达到69.0%,表明引发剂的加入可显著提高较低反应温度下的水热裂解效果.对反应前后油样进一步分析发现,反应样品中饱和分、芳香分、胶质和沥青质平均分子量均下降;饱和分、芳香分含量增加,而胶质、沥青质含量下降;胶质、沥青质中氢碳原子比增加,含硫量减少,含氮量变化不大;表明重质组分在水热裂解过程中发生了裂解反应、尤其是含硫官能团在水热裂解中发生了反应;反应样品沥青质及胶质芳香环系的缩合程度降低.实验结果表明,反应过程中稠油重质组分发生了裂解,而且胶质的裂解程度更大,轻质组分含量增加,导致稠油黏度降低、流动性提高,在一定程度上改善了稠油的品质;引发剂可以在较低温度下产生自由基,从而使水热裂解反应在较低反应温度下有效进行.     

原油空气氧化前后多环芳烃组分的气相色谱-质谱分析

采用柱层析法对空气氧化前后的原油进行族组分分离,利用气相色谱-质谱(GC-MS)分离测定其芳香烃组分,分析多环芳烃组分的变化.结果表明,随着氧化过程的进行,烷基化多环芳烃占多环芳烃的含量从氧化前的71.5%增加到92.0%(175℃)和90.2%(225℃).轻质组分萘和菲的优势逐渐被重质组分艹屈取代.侧链少的多环芳烃比侧链多的更易氧化.氧化后,其他稠环化合物蒽、萤蒽、芘、苯并蒽含量降低,苯并萤蒽含量增加;苯并芘在175℃氧化后含量降低,而在225℃氧化后含量增加.与此同时,175℃氧化后生成了原油所不含有的三芳甾烃、联苯和苯并呋喃.     

延长油田长2原油组分特征研究

采用柱层色谱分离法、热重法、傅立叶红外光谱、紫外光谱和偏光显微分析等表征方法,对采自延长油田某采油厂长2层原油样品进行了组分分离和分析,并对其热重行为、饱和烃组分结蜡行为等进行了研究.研究结果表明,在原油热重反应过程中,低温下主要是其轻、中组分(饱和烃、芳香烃)及水分的物理蒸发,高温下主要是重组分(胶质、沥青质)的物理蒸发及化学反应.显微分析发现原油中的胶质、沥青质等强极性组分使饱和烃组分冷却结晶时的蜡晶分散度增大,尺寸相对减小,颗粒数明显增多,蜡晶形状由片状三维网络结构变为颗粒状,因而蜡晶之间的联结度减弱,不易缔合形成大块蜡晶聚集体,说明该原油中的极性组分可以有效抑制原油的结蜡.     

水溶性有机钴(Ⅱ)盐催化的稠油低温清洁水热裂解

为了开发新型稠油低温清洁水热裂解催化体系,合成了系列钴盐催化剂,用于低温下催化稠油热裂解,利用高温高压反应釜模拟井下热采条件,在反应温度为180℃、反应时间为24h、催化剂Co-3加量为0.5%,稠油降黏率可达到84.5%.稠油组分分析表明:水热裂解催化反应后,胶质、沥青质等重质组分含量减少;TGA和GC显示稠油经水热催化裂解反应后,轻质组分含量明显增加.     

废轮胎热解油重质馏分制备的道路沥青老化性能研究

针对废轮胎热解油重质馏分(＞350℃)组成上具有蜡含量低,芳香分、胶质和沥青质含量高的特点,研究了废轮胎热解油重质馏分采用蒸馏法生产道路沥青的可行性。结果表明,废轮胎热解油中＞420℃、＞430℃、＞440℃三种渣油的性质可以满足不同牌号道路石油沥青老化实验前的技术指标,特别是延展性能优异,但是抗老化性能较差。渣油老化前后的族组成、官能团、氢分布及分子量分布变化表明,渣油在老化过程中存在氧化反应以及脱氢缩合反应,使渣油的化学组成发生变化,即芳香分、胶质含量减少,沥青质含量明显增加,使得沥青胶体体系中分散相明显增多而分散介质相对减少,造成热解油的渣油抗老化性能较差。     

A comprehensive analysis of the properties of light crude oil in oxidation experimental studies

The analysis of light crude oil for oxidation reaction experiments is a kind of important technological for evaluating an air injection project in a reservoir. In this study, the paper comprehensively analyzes the variations of Jilin crude oil composition comparing crude oil component’s variations before and after oxidation, and investigates the effluent gas composition and hydrocarbon, analyzes the mechanism of low temperature oxidation reaction (LTO), and rebuilds the light crude oil cracking reaction of intermediate component in a new pattern. In the early stage of the oxidation reaction, firstly, oxygen is captured by forming chemical bond in liquid hydrocarbon. And then oxygen takes part in the free radical chain reaction by forming hyperoxide and decomposes to ketones, aldehydes, alcohols, and so on. Meanwhile, chain scission reaction comes up. Research result shows that the intermediate components (C_7–17) of crude oil make great contribution to crude oil cracking. The experimental result shows that Jilin reservoir has the potential of implementing air injection project.     

马瑞原油在空气和氮气中的热解-氧化性能

低温氧化是注空气采油及原位燃烧采油技术中的重要化学反应,为深入认识原油在有氧环境下复杂热反应过程中的低温氧化特性,我们采用热重/差热分析法(TG/DTA)研究了线性升温和等温条件下马瑞(Merey)原油的热反应行为。 结果表明,Merey原油在空气及线性升温条件下的受热过程分4个阶段:气化段、低温氧化段、热解段和高温氧化段;相邻阶段的物理、化学主导过程的重叠增加了分析原油热反应特征的难度。 升温速率提高,气化段和低温氧化段的终止温度不变;热解段和高温氧化段的终止温度以及热解段的峰温随升温速率的增加而升高。 N₂气与空气下Merey原油的热重/微分热重(TG/DTG)数据对比表明,升温速率越高,空气下的高温氧化段与热解段重叠程度越大,这有利于燃烧但会降低原油采收率。 空气下等温时的TG/DTA结果表明随升温速率增加,升温至300 ℃时的失重率降低,不利于原油轻组分的气化。 反应温度越高,气化过程时间越长,失重分数越大。 Merey原油在低于300℃时低温氧化反应不是主导反应。     

Non-isothermal kinetic analysis and feasibilty study of medium grade crude oil field

In this research, non-isothermal kinetics and feasibility study of medium grade crude oil is studied in the presence of a limestone matrix. Experiments were performed at a heating rate of 10°C min⁻¹, whereas the air flow rate was kept constant at 50 mL min⁻¹ in the temperature range of 20 to 600°C (DSC) and 20 to 900°C (TG). In combustion with air, three distinct reaction regions were identified in all crude oil/limestone mixtures, known as low temperature oxidation (LTO), fuel deposition (FD) and high temperature oxidation (HTO). The activation energy values were in the order of 5–9 kJ mol⁻¹ in LTO region and 189–229 kJ mol⁻¹ in HTO region. It was concluded that the medium grade crude oil field was not feasible for a self-sustained combustion process.     

Kinetics of crude oil combustion

In this research, thermal characterization and kinetics of Karakus crude oil in the presence of limestone matrix is investigated. Thermogravimetry (TG/DTG) is used to characterize the crude oil in the temperature range of 20-900°C, at 10°C min ^-1 heating rate using air flow rate of 20 mL min ^-1. In combustion with air, three distinct reaction regions were identified known as low temperature oxidation (LTO), fuel deposition (FD) and high temperature oxidation (HTO). Five different kinetic methods used to analyze the TG/DTG data to identify reaction parameters as activation energy and Arrhenius constant. On the other hand different f(α) models from literature were also applied to make comparison. It was observed that high temperature oxidation temperature (HTO) activation energy of Karakus crude oil is varied between 54.1 and 86.1 kJ mol ^-1, while low temperature oxidation temperature (LTO) is varied between 6.9 and 8.9 kJ mol ^-1.     

Solubility Parameters Based on IR and NIR Spectra: I. Correlation to Polar Solutes and Binary Systems

IR and NIR spectra were correlated to Hildebrand and Hansen solubility parameters through use of multivariate data analysis. PLS‐1 models were developed and used to predict solubility parameters for solvents, crude oils, and SARA fractions. PLS regression showed potential for good correlation of the solubility parameters with IR and NIR spectra. Principal component analysis of IR spectra showed that crude oils are grouped according to their relative contents of heavy components such as asphaltenes. PCA of IR spectra for SARA fractions resulted in obvious groupings of the respective fractions. Prediction of solubility parameters from IR spectra of polymers, crude oils, and SARA fractions gave values that are comparable to literature values. This study indicates that correlation of solubility parameters with IR and NIR spectra is possible. In turn, it may be possible to develop models that can predict the polarities of crude oils and crude oil fractions such as resins and asphaltenes.