多孔滤膜抽滤法测定原油沥青质含量

摘要

The three separation methods (centrifugation,filtration and suction microfiltration)for measuring the asphaltenes content in crude oil were compared in this work.The suction microfiltration method was found having significant advantages in operation-safety,separation-efficiency and repeatability in measured values.In order to find the difference among these three methods,the residual particles in the supernatant or filtrate was measured using a laser particle analyzer.The results show that,the filtration method will result in more loss of asphaltenes particles than other methods.Several factors has been optimized for the suction method such as the blending time (30 min),the ratio of precipitant to oil (40 mL/g),and the sampling mass (1.0 g).Compare with the standard SY/T 7550—2004,the optimized measurement conditions in this study are reasonable and the test accuracy is acceptable.%对测定原油沥青质含量的3种分离方法(离心法、抽滤法、过滤法)进行对比，观察到抽滤法在安全健康、效率及重复性等方面具有明显优势。采用激光纳米粒度分析仪对3种分离方法的残液进行了粒度分析，结果表明，过滤法将导致较多的沥青质颗粒的损失，造成测量结果偏小。在此基础上，对抽滤法测试流程中涉及的剂油比、样品静置时间、取样量等影响因素进行优选，确定出适宜剂油比为40 mL/g、静置时间30 min、取样质量1.0 g。与SY/T 7550—2004标准方法相比，采用多孔滤膜抽滤法测定原油沥青质含量，推荐的参数合理，测试精度较高。