Page 171 - Petroleum and Gas Field Processing

Figure 14 Steps leading to large drop formation.

of bottles (12 or more). To each bottle, a few drops of different chemicals
are added, followed by shaking to ensure good mixing between the
emulsion and the chemical. Heat could be applied if needed. Final
selection of the right chemical will be based on testing a sample of the oil
to find out how complete the water removal was.
From the practical point of view, most oil deemulsifiers are oil
soluble rather than water soluble. Because such small amounts are used in
treating and to ensure thorough mixing, it is recommended to dilute the
chemical with a solvent to have a larger volume of the solution to inject.
The point of injection of deemulsifiers will depend largely on the type
used. For the case of water-soluble deemulsifiers, injection is carried out
after free water has been removed; otherwise, most of the chemical is lost
down the drain. Three points of injection are recommended:
1. Upstream of the choke, where violent agitation takes place in the
choke as the pressure is lowered from wellhead to that
corresponding to the gas/oil separator. It is considered the
ideal injection point. This is illustrated in Figure 15.

Copyright 2003 by Marcel Dekker, Inc. All Rights Reserved.