利用比重瓶和称量法测定原油含水率

Determination of Water Content in Crude Oil by Using Pycnometer and Weighing Method

原油或油品含水率的精确测量对原油的生产开采、计量、储存和使用十分重要，目前有多种测量的方法和仪器，在使用中各有特点。导出了密度和含水率的关系原理，采用实验室常用的比重瓶和天平为测量装置，通过对空比重瓶、装满待测油样后的比重瓶的质量测定，即可得出待测油样的体积含水率。对两种油品的实验数据显示：油样中含水率在1％-99％间，含水率测量值和真实值在0．5％内一致。而且，含水率大、小，水、油乳化和分层对测量精度没有影响。并分析了实际误差大于方法误差的原因。

Accurate measurement of water content in crude oil and oil product is very important in oil production, measurement, storage and usage. There are so many methods and instruments for measuring water content, in which, every method and instrument has its own characteristic. In this paper, the relation between the water content and density of the oil sample was derived and used as measurement principle; common inexpensive pycnometer and the balance were used to measure the water content of oil sample. The mass of the pycnometer full filled with oil sample was determined by the balance. Then the water content can be calculated by the derived equation. The experimental data show that the measurement errors are almost within 0.5% for the oil samples with water content of 1%-99% . Furthermore, the precision of measurement is not affected by water content, emulsification and phasesplitting between water and oil. Finally, the methodic error and experimental error were discussed.