红河油田轻质原油低温氧化实验及动力学研究

LTO experiment and kinetics analysis of light crude in Honghe oilfield

红河油田长8油藏为超低渗轻质油藏,采用空气驱是提高长8油藏原油采收率的一种有效方法。通过室内低温氧化实验对红河油田原油与空气低温氧化反应规律及反应动力学进行了研究。结果表明,红河油田长8油藏原油能与空气发生低温氧化反应,反应速率随反应温度和初始压力的升高而增大。氧化反应之后,原油中饱和烃含量变化不大,芳烃含量有所降低,胶质、沥青质含量有所升高,脱气原油黏度增大。由于氧化反应生成二氧化碳等气体,未脱气原油黏度降低。动力学研究表明,长8原油低温氧化活化能在15~21 kJ/mol之间,并且随压力的升高而降低,表明红河油田长8原油较易发生低温氧化反应,并且压力越大,反应越易进行。

Air drive is an effective method to enhance oil recovery of Chang-8 reservoir, the ultralow permeability light oil reservoir in Honghe oilfield. The low temperature oxidation （LTO） reaction rules and reaction kinetics of crude and air in Honghe oilfield were studied through laboratory low temperature oxidation experiments. The results showed that the LTO reaction could occur be- tween crude and air of Chang-8 reservoir in Honghe oilfield, and the reaction rate increased with the increasing reaction tempera- ture and initial pressure. After oxidation reaction of crude, the saturated hydrocarbon content changed little, the aromatic hydrocar- bon content decreased, and the gum and asphaltene content increased, which brought about the increases of viscosity of degassed crude. Due to the carbon dioxide generated during the oxidation reaction, live crude viscosity decreased. Reaction kinetics research- es showed that, the activation energy of LTO reaction was 15-21 kJ/mol, and decreased with the increasing pressure. All these above showed that, the LTO reaction occured easily in Chang-8 reservoir of Honghe oilfield. The higher the pressure was, the more easily the LTO reaction oceured.