原油采出液在集输过程中极易发生乳化，而原油中的沥青质、环烷酸等活性物质对乳状液的稳定性有重要影响。为深入探究环烷酸与沥青质协同影响乳状液稳定性的机理，以反-4-正戊基环己甲酸（反-4）为代表性环烷酸，以塔河稠油中提取的沥青质为代表性沥青质，分别通过瓶试法、显微观察法和界面实验研究了反-4、反-4与沥青质二元体系以及在此基础上添加盐离子对乳状液稳定性的影响。结果发现，单独环烷酸形成的乳状液稳定性远低于沥青质；当环烷酸与沥青质共存时，油水界面主要以沥青质吸附为主，沥青质是决定乳状液稳定性的主导因素；而在加入盐离子后，其与环烷酸相互作用会增强环烷酸的界面活性，导致界面上大量环烷酸盐取代沥青质，从而弱化界面膜结构，最终减弱乳状液稳定性。

Water-in-oil emulsion is inevitably formed during the process of gathering and transportation, and the active substances such as asphaltene and naphthenic acid in crude oil may exert important effects on the emulsion stability. To explore deeply the synergistic influence mechanism of naphthenic acid and asphaltene, trans-4-n-pentylcyclohexanecarboxylic acid (trans-4) was chosen as the representative naphthenic acid while the asphaltene extracted from Tahe heavy oil is used as the representative asphaltene. The impacts of sole trans-4, trans-4 and asphaltene, and further the addition of saline ions on the emulsion stability were explored with bottle test, microscopic observation and interfacial experiment. It is found that the emulsion formed by sole naphthenic acid is much less stable than that formed by sole asphaltene. When naphthenic acid and asphaltene coexist, the oil-water interface is mainly adsorbed by asphaltene which dominates the emulsion stability. However, once the saline ions are added, they can interact with the naphthenic acid, resulting in the adsorption of more naphthenic acid at the interface. As a result, the interfacial structure is weakened and thus the emulsion stability is deteriorated.