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more money while generating less income because the volume of oil sold will
be based on the contract value of the B.S.&W.
The basic principles for the treating process are as follows
1. Breaking the emulsion, which could be achieved by either any, or
a combination of the addition of heat, the addition of chemicals,
and the application of electrostatic field
2. Coalescence of smaller water droplets into larger droplets
3. Settling, by gravity, and removal of free water
The economic impact of these treating processes is emphasized by Abdel-
Aal et al.[8].
5.2 OIL EMULSIONS
Rarely does oil production takes place without water accompanying the
oil. Salt water is thus produced with oil in different forms as illustrated in
Figure 1. Apart from free water, emulsified water (water-in-oil emulsion) is
the one form that poses all of the concerns in the dehydration of crude oil.
Oil emulsions are mixtures of oil and water. In general, an emulsion can
be defined as a mixture of two immiscible liquids, one of which is dispersed as
droplets in the other (the continuous phase), and is stabilized by an
emulsifying agent. In the oil field, crude oil and water are encountered as the
two immiscible phases together. They normally form water-in-oil emulsion
(W/O emulsion), in which water is dispersed as fine droplets in the bulk of oil.
This is identified as type C in Figure 2. However, as the water cut increases,
Figure 1 Forms of saline water produced with crude oil.
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