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294 Chapter 6

Table 6.13 Dispersed-Phase Parameter in Liquid-Liquid Separation

9 Result

<0.3 light phase always dispersed
0.3 - 0.5 light phase probably dispersed
0.5 - 2.0 phase inversion probable,
design for worst case
2.0-3.3 heavy phase probably dispersed
>3.3 heavy phase always dispersed

Source: Ref. 19.

Table 6.14 Effect of Turbulence on Liquid-Liquid Separation

Reynolds Number Effect

<5000 little problem
5000 - 20,000 some hindrance
20,000 - 50,000 major problem may exist
>50,000 expect poor separation

Source Ref. 21.

Liquid-liquid separation is hindered by turbulence. Bailes et al. [21] deter-
mined the effect of turbulence on the separation, which is given in Table 6.14. The
separator diameter is calculated to minimize turbulence. Increasing the separator
diameter reduces the Reynolds number and therefore turbulence. Thus, use Table
6.14 as a guide in calculating the diameter. Because there are two phases, calculate
the Reynolds numbers for both the light and heavy phases. Because the flow area
for both phases is not circular, the diameter in the Reynolds number must be re-

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