Vacuum Bottoms Sample after
Water-Push and Steaming
Vacuum Bottoms Sample with
TC-5000 Oil-in-Water Emulsion
Vacuum Bottoms Sample
after TC-5000 Wash
Before the wash procedure is initiated, refinery personnel will complete the normal plant shutdown procedure. All equipment to be decontaminated will be pumped out and depressurized. Heavy circuits will be flushed with light oil at maximum velocities in order to bring down the pour point of the remaining heavy hydrocarbon below 90 degrees C. Following this step, predetermined circuits will be pushed with water or steam to displace free hydrocarbons as needed.
Once most of the free oil is displaced (free oil must not exceed 40% of loop volume) the system is charged with water to normal operating levels and placed under self-sustained circulation. Steam injection is used to raise the temperature of the circulating solution between 80 to 90 degrees C.
The system is normally circulated for a period ranging between 8 to 12 hours. During the decontamination process, the equipment will be vented first to the flare system and afterwards to the atmosphere.
The temporary pumps used to circulate the water/chemical solution, if any, will be connected to the process equipment by means of temporary piping spools and high-pressure-and-temperature rated hoses.
The effluent generated during the decontamination process is typically pumped off to a holding tank, where the aqueous phase is then discharged to the plant waste water system and the oil is sent to the slop tank for re-processing.