Chapter 6
6. Conclusions and future work
6.1. Conclusions
6.1.1. Emulsion characterization by NMR
Stable water in diluted bitumen emulsions persist in the absence of a
demulsifier. The coalescence rate of the emulsion is very slow and is difficult to
observe, even if most of the clay solids are removed by centrifuge before the
emulsion preparation. The sedimentation rate is much faster compared with
coalescence. Sedimentation rate of emulsion sample with solid is larger than that
without solid.
PR5 is an optimal demulsifier for the brine in diluted bitumen emulsions. For
emulsion samples with and without solids, PR5 can accelerate the coalescence
rate. For the sample without solids, almost complete separation can be obtained;
for the sample with solids, the separation is incomplete and a rag layer, which
contains solids and has intermediate density, forms between the clean oil and free
water layers. This rag layer prevents further coalescence and complete
separation of the emulsified water.
NMR CPMG method can measure the T2 distribution of water in diluted
bitumen emulsions. But in emulsion sample with solids and no PR5, T2
distributions of dispersed water phase and continuous oil phase are not
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