基于Friedman方法计算稠油氧化反应活化能出现负值的原因分析  

Analysis of the reasons for negative values in calculating the activation energy of heavy oil oxidation reaction based on Friedman method

作　　者：孙梓齐 赵仁保[1] 郑懿琼[2] 张情情 李东旭[2] SUN Ziqi;ZHAO Renbao;ZHEN Yiqiong;ZHANG Qingqing;LI Dongxu(State key Laboratory of Petroleum Resources and Prospecting,China University of Petroleum(Beijing),Beijing 102249;The No.1 Oil Production Plant of Xinjiang Oilfield Company,Karamay 834000)

机构地区：[1]油气资源与工程全国重点实验室(中国石油大学(北京)),北京102249 [2]中国石油新疆油田分公司采油一厂,新疆克拉玛依834000

出　　处：《长江大学学报（自然科学版）》2024年第6期107-112,共6页Journal of Yangtze University(Natural Science Edition)

基　　金：新疆维吾尔自治区高层次人才引进项目“基于垂向火驱井网条件下超稠油的原位改质辅助开发机理研究”(JXDF0221)。

摘　　要：通过实验得到不同升温速率下稠油氧化反应温度和产出CO+CO_(2)体积分数的变化规律,利用Friedman方法计算了稠油氧化反应的活化能,并分析了活化能出现负值的原因。结果表明:稠油氧化反应的平均活化能为189.44 kJ/mol;转化率在0~0.36(245~305℃)时,活化能逐渐增加至271.16 kJ/mol;转化率在0.585~0.695(365~395℃)时,活化能为负值;转化率高于0.625时,反应活化能快速增加至468.64 kJ/mol。出现负活化能的原因是稠油的氧化反应速率随温度升高而出现降低的趋势,在同一转化率时,高升温速率(2.92℃/min)下的反应速率低于低升温速率(1.64℃/min)的反应速率,3种不同升温速率下的稠油氧化反应速率的对数值与温度的负倒数之间线性关系变差,拟合得到的斜率为负值。该研究分析了稠油氧化反应过程中计算出负活化能的原因,所得到的认识对稠油氧化反应动力学特征的研究具有重要的参考价值。In this work,the variations in temperature and the volume fraction of CO+CO_(2)produced during the oxidation reaction of heavy oil were obtained at different heating rates.The activation energy of the heavy oil oxidation reaction was calculated using Friedman method,and an analysis was conducted to understand the reasons for the appearance of negative values in the activation energy.The results indicate that the average activation energy of the heavy oil oxidation reaction is 189.44 kJ/mol.The activation energy gradually increases to 271.16 kJ/mol in the conversion range of 0 to 0.36(temperature range 245~305℃).However,in the conversion range of 0.585 to 0.695(temperature range 365~395℃),the activation energy becomes negative.Beyond a conversion rate of 0.625,the reaction’s activation energy rapidly increases to 468.64 kJ/mol.The occurrence of negative activation energy is attributed to the diminishing trend in the oxidation reaction rate of heavy oil with increasing temperature.At the same conversion rate,the reaction rate at a higher heating rate(2.92℃/min)is lower than that at a lower heating rate(1.64℃/min).The logarithm of the reaction rate at three different heating rates in heavy oil oxidation shows a deteriorating linear relationship with the negative reciprocal of temperature,resulting in a negative slope.This study analyzes the reasons for the calculated negative activation energy in the process of heavy oil oxidation reaction.This study analyzed the reasons for calculating the negative activation energy during the heavy oil oxidation reaction,the results are of great significance to the kinetic characteristics of heavy oil oxidation reaction.

关 键 词：火烧油层 Friedman方法 氧化反应 活化能 稠油 

分 类 号：TE357.44[石油与天然气工程—油气田开发工程]