【摘要】 从MD膜驱剂与原油界面活性组分沥青质模型油的界面张力出发,考察了作用时间、水相pH、MD膜驱剂质量浓度、盐浓度、沥青质含量、芳香度、温度等对模型油/水界面张力的影响,并根据扩散控制机理解释了动态界面张力初期过程,进一步揭示了MD膜驱油技术的机理。结果表明,沥青质模型油/MD膜驱剂溶液的界面张力先随时间增加而降低,约15min后达到平衡,达到平衡之前的过程基本上符合扩散控制过程;MD膜驱剂的加入并不能改变pH对模型油/水界面张力的影响趋势;在所考察的条件范围内,沥青质模型油/水溶液的界面张力不随MD膜驱剂质量浓度增加而改变,其值约为19 65mN/m;NaCl对界面张力的影响不明显;沥青质质量浓度从0增加到1000mg/L时,模型油/水和模型油/MD膜驱剂溶液的界面张力分别从23 4mN/m和22 0mN/m逐渐下降至20 0mN/m和18 8mN/m;温度从25℃升高到45℃时,模型油/水溶液的界面张力降低;但芳香度从0增加到100%时,其界面张力均从21 0mN/m增加至31 5mN/m。MD膜驱剂是表面非活性物质,在驱油时不存在低界面张力提高采收率的机理。更多还原

【Abstract】 The interfacial tension between asphaltene model oil and molecular deposition filming flooding (MDFF) agent aqueous solution were investigated using MDFF agent aqueous solution and deionized water as the water phases.The influences of pH value,mass concentration of MDFF agent,salinity,mass concentration of asphaltene and the aromaticity on the interfacial tension were discussed.The interfacial tensions for both model oil/deionized water and model oil/MDFF agent aqueous solution decrease with increasing time and balance after 15 min.The equilibrium kinetics are evaluated assuming the process to be diffusion controlled.The effect of pH on interfacial tension between model oil and water doesn’t change due to addition of MDFF agent.The interfacial tension,about 19.65 mN/m,keeps constant when mass concentration of MDFF agent increases,and the influence of salinity on the interfacial tension is not distinct.The interfacial tensions for model oil/deionized water and model oil/MDFF agent aqueous solution decrease respectively from 23.4 mN/m and 22.0 mN/m to 20.0 mN/m and 18.8 mN/m when asphaltene mass concentration rises from 0 to 1000 mg/L.They decrease with increasing temperature from 25 ℃ to 45 ℃,but increase from 21.0 mN/m to 31.5 mN/m when the volumetric content of p-xylene rises from 0 to 100%.As a surface-inactive agent,MDFF agent can’t decrease the interfacial tension,therefore,in the process of oil displacement,low interfacial tension mechanism doesn′t works.更多还原