不同质量浓度沥青质溶液界面性质及粒径分布研究

Study on the Interfacial Properties and Particle Size Distribution of Asphaltene Solution with Different Mass Concentrations

摘要: 沥青质是原油里面的一种活性组分，对原油乳状液稳定性起着重要作用。采用界面张力仪、表面黏弹性仪研究了从渤海SZ36-1油田A7井原油中提取的沥青质组分配制成的模拟油与A7井模拟水间的界面张力、界面剪切黏度，并利用纳米粒度分析仪测定了不同质量浓度沥青质溶液的粒径分布形态。研究表明，沥青质模拟油–模拟水体系界面张力随沥青质质量浓度增加而逐渐降低；沥青质质量浓度为1、3、5 mg/L时，沥青质模拟油–模拟水体系界面剪切黏度随沥青质质量浓度增加而增加；沥青质质量浓度介于10~30 mg/L时，沥青质模拟油–模拟水体系界面剪切黏度随沥青质质量浓度增加而减小；沥青质质量浓度介于30~100 mg/L时，沥青质模拟油–模拟水体系界面剪切黏度随沥青质质量浓度增加变化不大。沥青质质量浓度低于20 mg/L时，沥青质在二甲苯–煤油体系中粒径分布均一，且随着沥青质质量浓度增加，沥青质分散粒径增大；沥青质质量浓度高于20 mg/L时，沥青质在二甲苯–煤油体系中粒径分布范围较宽，且出现多个峰值，沥青质分子呈缔合分布状态。该研究成果有助于沥青质对原油乳状液稳定性影响机理的研究，对油田采出液进行破乳分离具有一定的指导意义。

Abstract: Asphaltene was an active component in crude oil, it played an important role in maintaining the emulsion stability of crude oil. The simulated oil synthesized by asphaltene components from Well A7 of SZ36-1 Oilfield in Bohai Area was simulated by using interfacial tension meter and SVR-S in-terfacial viscoelastic meter. The distribution shape of the asphaltene particle in different densities was measured by nano particle analyzer. Results showed that with the increase of asphaltene mass concentration, the interfacial tension of asphaltene simulated oil-water system was reduced gradually. With the increase of asphaltene mass concentration, the interfacial shear viscosity was raised gradually when the concentration of asphaltene was between 1 - 5 mg/L, it was reduced gradually when the concentration of asphaltene was between 10 - 30 mg/L and changed little when the concentration of asphaltene was between 30 - 100 mg/L. When the mass concentration of asphaltene was lower than 20 mg/L, it presented uniform particle size distribution in xylene/ kerosene solution. The average particle diameter increased with the increase of mass concentration of asphaltene. The asphaltene shows multiple peaks and wide particles distribution in xylene/ kerosene solution when the mass concentration of asphaltene is above 20 mg/L. It shows the as-sociated distribution status of the asphaltene particles. The result is favorable for studying the in-fluential mechanism of asphaltene on the stabilization of emulsion.