The vast majority of decontamination work is performed by Vapor Phase. The JPX is injected
directly into the purge stream that is used in the normal steam out process during shutdowns. The
JPX is carried throughout the column contacting all surfaces, breaking down the hydrocarbons
into lighter ends that are carried overhead to the flare system and emulsifying the heavier
hydrocarbons to be drained from the column with the condensate.
This Vapor Phase process greatly reduces decontamination time, wastewater generation, and
chemical cost, but provides H²S, Benzene LEL removal, so that the equipment is ready to enter
after a cool down water flushing rinse.
JPX/JPX-E can be applied by circulation to target packed beds that may be more heavily
contaminated or be at risk from Iron Sulfide, pyrophoric materials. Typical circulation solution
concentrations are from 1% to 3%.
A third application type would apply to horizontal vessels that have known sludge
accumulations, such as desalters or gas recycle KO drums.
The vessel is typically filled to 1/3 level and JPX/JPX-E is added to the steam heated water. The
mix is boiled and agitated to provide maximum sludge liquid content. The sludge hot water
slurry is then pumped out of the vessel and the vessel is re-steamed to relief to purge all vapors
in preparation for entry.
An auxiliary step when pyrophoric material is suspect of being present is to add JPX-EE (a mild
oxidizer and solubilizer) to the rinse water; this neutralizes the pyrophoric iron sulfides and
allows them to be rinsed from the internals of the columns.
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