Page 177 - Petroleum and Gas Field Processing

Figure 20 Effect of an electrical field on coalescence.

remnant emulsified water is separated as explained earlier. Finally, clean
oil flows to the top of the treater.
It should be made clear that most of the emulsified water is removed
by the dual action of both heat and chemicals before the oil passes to the
electric grid. The water content in the oil could be reduced to 1–0.5%
before it gets to the grid.
The application of the electrical field has a significant impact on the
treater’s performance. This is exemplified by Figure 20, which clearly
illustrates the improvement of a treater when an electric field is applied.

5.8 DESIGN OF TREATERS

In the present discussion, we shall limit our design consideration to
determination of the dimensions of the coalescing section and the heat
input requirement.
In order to achieve a certain quality for the treated oil (i.e., certain
maximum water content), we must determine the smallest water droplet
size that must be removed. The temperature of the emulsion, the retention

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