The name is absent

Chapter 5

bitumen emulsion.

The separation procedure can be divided into three steps. The first step is
emulsion coalescence and clean oil separation with PR₅ and silicate. The second
step is clay solids separation from the rag layer by increasing pH and shaking.
The last step is separation of the resulting oil-in-water emulsion by lowering the
pH. Each step is studied to find optimal separation conditions.

5.2. Materials and emulsion preparation

Samples OfAthabasca bitumen froth were provided by Syncrude Canada Ltd.
Diluted bitumen samples were prepared by diluting with naphtha with dilution ratio
0.7. The density of diluted bitumen with dilution ratio 0.7 is 821 kg∕ mɜ and the
viscosity is 7.10×10^³ Pa∙s (50 ⁰C). The diluted bitumen contains 1.0 w.% solids
and less than 2.0 w.% water, which can be measured by centrifugation. Most of
the solids and water can be removed by centrifugation at 3500 g for 30 minutes.

Unless otherwise stated, the aqueous phase used here is synthetic brine with
2.5×10^² M NaCI, 1.5×10'² M NaHCO₃, 2×10^³ M Na₂SO₄, 2×10^⁴ M CaCI₂ and
2×10'⁴ M MgCI₂. The pH of synthetic brine is 8.3.

Different additives (e.g. Na₂SiO₃) were added the brine prior to emulsion
preparation. Emulsion samples (60 ml) were prepared by mixing 30 ml brine and
30 ml diluted bitumen in a glass tube with a six-blade turbine (Figure 3.8). Stirring

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