Q & A > Question Details
In our vacuum distillation column three valve trays are replaced from glistch packing in order to obtain more deeper cut of SAE-40 and wash recycle is provided to wash the packing but whenever unit is down due to any failure the wash recycle line gets plugged. We are using SAE-20/SAE-10 as a wash recycle oil. Can we use HVGO for that purpose or any other solution for that problem?
08/02/2014 A: Celso Pajaro, Sulzer Chemtech, celso.pajaro@sulzer.com
Please clarify if the line outside the column gets plugged, or it is the distributor that gets plugged, also please clarify what kind of distributor do you use.
What you describe looks like the inlet distributor is plugged due to coke formation during the shut down, I am not so sure changing the fluid will solve the problem, I will look at the distributor design and to implement an emergency flush system that keeps fluid flowing thru the line during the emergency.
07/02/2014 A: Lindsay McRae, Pall Corporation, Lindsay_McRae@pall.com
Are your spray bars being fouled perhaps by contaminats in the wash oil? That can cause improper washing of the packings and then fouling & maldistribution. If so, you may want to install an appropriate duplexed filter unit to remove coke and corrosion products to enable your spray bars to be working more efficienctly.
06/02/2014 A: Ralph Ragsdale, Ragsdale Refining Courses, ralph.ragsdale@att.net
HVGO is typically used for the wash oil. It is unusual for the piping to plug. There is typically a filter in the line with a bypass for cleaning. Plugging often occurs on the top of the packing if the spray nozzles are not the right design or not installed in an effective overlapping spray pattern.