Chapter 3
separation results. Compared with other samples, emulsion sample adding PR5
can get more separated oil and water and has the best separation. PR5 is selected
as the optimal demulsifier.
Control PRi PR2 PR3 PR4 PR5 PR5
Figure 3.9 24 h emulsions with 200 ppm demulsifiers at 30 0C, N/В ratio 2.4
3.6.2. Emulsion characterized by CPMG T2 distribution measurement
Figure 3.10 shows T2 distribution of layered water/ diluted bitumen (sample 3,
dilution ratio 2.4, solids-free) mixture and water in diluted bitumen emulsion. The
red curve is T2 distribution of layered water/ diluted bitumen mixture, the blue one
is that of water in diluted bitumen emulsion. For both curves, oil and water have
different T2 distribution peaks, which are distinguishable. T2 values of oil peak in
emulsion are smaller than those of bulk oil. This indicates surface relaxation
effects on the continuous oil phase. T2 values of water drops in emulsion are
smaller than those of bulk water. The difference between the two peaks can be
used to calculate drop size distribution according to Eq. 3.6, if surface relaxivity p
is known. Combined with NMR restricted diffusion measurement, drop size
61