How do you calculate power density for a crude desalter unit for a given grid area? Also, is there any correlation between the droplet size and electrostatic field strength?
Answers
|
07/09/2010
|
A:
|
Eric Vetters, ProCorr Consulting Services, ewvetters@yahoo.com
"Power Density" is normally reported as KVA per sq ft. It is normally calculated by dividing the total KVA of transformer capacity by the centerline area of the desalter (T-T length x Diameter). This measure provides a rough indication of the ability of the electric field to cause water droplets to coalesce. The heavier the crude the higher the required KVA/sq ft because per stokes law larger droplets (stronger electrice field to drive coalescence) are needed produce the same settling velocity. The stronger the electric field the better it can promote water droplet coalescence. You can view it as either creating larger droplets or allowing smaller droplets to be created across the mix valve and still provide enough coalescing power for the droplets to settle in the desalter.
|