Chapter 5
80 0C with similar procedure as described in sections 3.5.2 and 3.5.3. Water
content in oil layer is measured by K-F titration, as described in section 5.7.2.
5.8.1.2. Solid content and distribution by centrifugation
Solids in different layers of partially separated emulsion were collected by
centrifugation at 8000 g for 30 minutes. Here solid distribution in oil layer
(oil-continuous phase on the top with small amount of water and solid), rag layer
(water- continuous phase with oil and solid skins in the middle) and bottom layer
(water layer with solid sediments at the bottom) is studied. After centrifugation,
water and oil were removed and the open centrifuge tube was put in the oven (50
0C) overnight for drying. Weight of solid was measured and solid content in oil
layer was calculated based on original weight of oil layer. Solid distribution was
calculated based on solid in each layer and total weight of solid by centrifugation.
5.8.2. Results and discussions
5.8.2.1. Separation of solids-free emulsion
Figure 5.15 shows the photograph of brine in diluted bitumen with N/В ratios
0.7 and 4.0 24 h emulsion samples adding 200 ppm demulsifiers PRi to PR6 at 80
0C. The first sample is emulsion without any demulsifier as control. The second to
the seventh are emulsion adding 200 ppm PRi to PR6. The pH of the aqueous
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