SOUND-VELOCITY STUDIES OF PIPELINE OILS AS A FUNCTION OF VISCOSITY, DENSITY AND WATER-CONTENT

Measurements of velocitiy of sound in crude oil samples taken from a p ipeline have been made as a function of oil temperature and added amou nts of water and diluent (toluene). In the case of low concentrations of water-in-oil, the experimental sound velocities show a linear depen dence on wt % of added water. For the diluent-in-oil systems the,exper imental sound velocity can be predicted over a wide concentration rang e of diluent by assuming an ideal mixing law for the sound velocities of the individual components. It is observed that the sound velocities for a number of the water-free oils show a strong dependence on the s ource of the oil. Of further interest is the observation of a good cor relation between the measured viscosity and density properties with th e measured sound velocities for the oil samples as obtained from the p ipeline. These preliminary results suggest some potentially important deliverables. In particular, that rapid and frequent on-line monitorin g of the sound velocity property of an oil or oil mixture may provide accurate estimates of: (i) viscosity; (ii) density; (iii) wt % diluent -in-oil for conditions < 50 wt % added diluent; and (iv) wt % water-in -oil for conditions < 10 wt % added water.