孤东油田有机碱与原油相互作用界面张力变化规律

Study on interfacial tension variation rule under interaction between organic alkali and crude oil in Gudong oilfield

为了深入认识碱与原油之间的作用规律,对酸值较高的孤东油田原油进行了研究,通过提取石油酸,切分原油组分,考察了碱的类型、pH值对不同原油组分模拟油界面张力的影响。实验结果表明:有机碱和无机碱分别与孤东油田原油作用,界面张力变化规律不同,随着溶液pH值的升高,无机碱溶液使孤东油田原油界面张力下降至最低值后不再变化,而有机碱溶液使原油的界面张力先降低后升高,界面张力最低值对应的有机碱质量分数为1.0%;有机碱与原油酸性组分作用生成活性物质,可降低界面张力,使动态界面张力曲线呈"V"形或"U"形;有机碱与原油中的胶质、沥青质组分作用均可产生活性物质,初始界面张力最低,后逐渐升高;有机碱与原油中饱和分、芳香分之间没有相互作用。

In order to understand the interaction rule between alkali and crude oil,the Gudong crude oil is separated into acidic components,resin and asphaltene,saturated hydrocarbons,aromatic hydrocarbons.The Gudong crude oil as the study object has high acid value.The interfacial tension between the aqueous solution of alkali and simulated oil is investigated through changing the alkali type and value of pH.The result shows that the rule of organic alkali decreasing interfacial tension is different from that of inorganic alkali.With the increase of pH,the interfacial tension between organic alkali and Gudong crude oil decreases at first and then increases.When the organic alkali concentration is 1%,the interfacial tension is lowest.The dynamic interfacial tension between acidic component simulation oil and the aqueous solution of organic alkali varies with time,and the interfacial tension-time curve shows the shape of'V'or 'U'.Through the variation of interfacial tension between aqueous solution of organic alkali and resin simulated oil and asphaltene simulated oil,it can be seen that the organic alkali can react with the acidic components in resin and asphaltene.However,the organic alkali can't react with saturated hydrocarbons and aromatic hydrocarbons.