Vapor Phase Chemical Cleaning (Injecting chemicals + steam)

Vapor-Phase Chemical Cleaning

Principles:

Chemical injected Into steam.
Continuous injection of fresh chemical.
Continuous monitoring of hydrocarbon levels.
De-oiling, degassing & Sulphide oxidation (no Pyrophoric).
Minimal changes in operational steam-out procedures.

A typical Vapor-Phase Application (Vacuum Tower)

Vapor-Phase chemical-steam-water manifold

Key Vapor-Phase Advantages:

Minimizes Down Time
Reduces Steam Out Duration
Reduces Maintenance Activity Before and After Decontamination Process
Environmentally Friendly
Biodegradable
Extremely Low Chemical Oxygen Demand (COD) Waste
Does not make Stable Emulsions
Minimizes the amount of waste generated

Pre-flushing and Post-flushing advantages

Pre Flushing

PHelps reduce surface tension and remove free solids.
PPenetration and softening of Atmospheric Residue.
PAssures chemical contact of solids in packed sections and dead spots.

Post Flushing

Assures chemical saturation and neutralization of pyrophoric in large packed sections.
PHelps to carry out free solids.
PWill rinse out residual chemical and reduce odor.
POxidized rinse water helps with effluent disposal.

Steam is traveling upwards. This carries chemicals throughout the equipment, even to the underside trays. Condensation is constantly working downward – also carrying chemicals.

This promotes penetration and oxidation everywhere in the unit.

Pre-flushing and Post-flushing with chemicals allow additional oxidizing and washing treatment.

It is possible still to have untreated deposits deep within some zones, but everything that can be reached WILL be reached.

Combination of Vapor-Phase and bottom circulation

Bottom section of process equipment is liquid filled and circulated with either process pumps if possible or diesel driven high volume circulation pumps.

Top section or OVHD is vapor phased through side stripper or temporary steam connection.