Periodic inspection of the jacket is an important examination to add in your maintenance regimen if it’s not already included. A regularly scheduled analysis will help to extend the life of your vessel (and only DDPS provides one or more jacket clean-out ports specifically for this purpose!).
DDPS jacketed vessels are equipped with a vent coupling at the top of the jacket shell and a drain coupling in the lower jacket expansion diaphragm near the vessel outlet. The recommended practice is to connect the top vent line with a valve and vent whenever liquid is first injected into the jacket. This removes all air and permits full heat transfer. It also prevents corrosion of the upper closure. The diaphragm drain should be opened at least once a week during operation to clean out all accumulated deposits and periodically “blown down” to remove sludge from the expansion ring, to prevent premature failure due to corrosion.
When it is determined that the jacket must be cleaned due to mild fouling (especially due to brine usage), we recommend a 15% solution of sodium hypochlorite (see our Glass-Lined Equipment Maintenance Manual for more information on jacket capacities). After cleaning, all jacket-agitating nozzles should be inspected and replaced if needed. There are cases, however, when fouling is moderate to severe and more aggressive action needs to be taken.