摘要
基于黄金管模拟实验对原油裂解的动力学及控制因素进行了研究。通过气态烃的定量分析,发现原油的持续裂解使得总裂解气体积及CH4产量不断增加,而C2-5的产量则先增加后减少。动力学计算可得,HD11井原油裂解生气总反应的平均活化能为59.8 kcal/mol(250.0 kJ/mol),频率因子A为2.13×1013s-1。残留原油组分的色质分析结果表明,不同族组分的相对稳定性存在差异,且原油中的大分子更容易发生裂解。同时,不同介质条件下的对比实验结果及前人的研究,都证实了压力、水及粘土矿物等因素很可能影响甚至控制原油的裂解。尽管作用机制不同,高压和水的存在都能抑制裂解过程中的自由基链反应,从而起到提高原油稳定性的效果。而粘土矿物,尤其是蒙脱石或伊/蒙混层矿物,则会通过酸催化作用加速原油或烃类的裂解,且裂解气产率与矿物表面的Brnsted酸位强度成正相关。
This paper studied the kinetics and controlling factors for oil cracking process by gold-tube pyrolysis experiments.Yields analysis of the gas hydrocarbons generated from pyrolysis of HD11 crude oils indicated that the yields of total gas and methane increased with the heating process,while a sudden decrease occurred following an initial increase for that of C2-5 due to their subsequent cracking.The average active energy and frequency factor A for total cracking reaction of HD11 crude were calculated to be 59.8 kcal/mol（250.0 kJ/mol）and 2.13 ×10^13 s^-1 separately.GC-MS analysis results revealed that the relative stability of different fractions varied and larger organic molecular seemd to be more readily cracked.Meanwhile,results of a series control experiments and former works demonstrated that potential factors,involving pressure,water and clay minerals,could affect or even dominate the cracking of oils.Despite working in different mechanism,both high pressure and the presence of water could inhibit the free radical reactions and consequently promote the stability of oils.On the contrary,clays,especially montmorillonite or illite-smectite（I/S）,could avail the cracking of oils or hydrocarbons due to the catalysis initiated by their surface acid sites.Furthermore,it was substantiated that there was a positive relation between the catalytic effects of gases with the strength of Brnsted acids on clays.
出处
《天然气地球科学》
EI
CAS
CSCD
北大核心
2011年第2期211-218,共8页
Natural Gas Geoscience
基金
国家自然科学基金(编号:40773032)
国家重大专项(编号:2008ZX05007-001)
中国石油天然气股份有限公司科技项目(编号:2008A-0600)联合资助
关键词
原油裂解气
黄金管热模拟
动力学
压力
水
粘土矿物
Oil-cracking gas
Gold-tube pyrolysis
Kinetics
Pressure
Water
Clay minerals.
