Unit School Questions Flashcards
What is the purpose of C-6105, 1st Side Cut Stripper?
To remove light ends from HSR using 60 psig stripping steam and return those light ends to C-6101 through the overhead vapor line
Why would you bypass E-6131 A/B?
To enable hot feed to be routed to HDS1 hydro treater to become CCR feed
What are the main crude feed tanks for Crude 2?
Tk-400, 401, 402, 403, 404, 405
What is the correct slow roll speed for TP-6101A?
Slowroll speed is 800 RPM
What should you do at the outside control panel to shut down TP-6101A in an emergency?
PULL E-STOP Button to shut down TP-6101A turbine
What is the purpose of the Primary Pre-Heat Train?
Heats raw crude feed to 260-320 degrees F, to ensure good Desalter operation and cools unit product streams
At what temperature do the Desalters normally operate?
They operate between 260 to 305 degrees F.
320 Max
Why is water injected at the discharge of the Main Feed Pumps (P-6101/A)?
Water is mixed with crude ahead of the heat exchangers to help protect them from salt deposits
How do we ensure the accuracy of the flow indication reading on FI-2138?
The reading must be corrected for the current API gravity of the incoming crude feed.
What is the purpose of the Flash Drum, D-6130?
Allows the light ends and trace water in the crude from the desalters to vaporize
Why is the Flash Drum, D-6130, elevated?
The Flash Drum is elevated to hold good suction head on the secondary crude feed pumps without increasing Flash Drum pressure.
At what pressure do we operate the Flash Drum, D-6130?.
The Flash Drum operates on Atmospheric Column Pressure
How do we control foaming in the Flash Drum, D-6130?
Foaming is controlled by a stream of hot crude recycle which maintains Flash Drum bottoms temperature above 310 degrees F.
What is the primary source of heat in the Secondary Pre-Heat train
Residuum is the primary source of Secondary Pre-Heat
What should you do at the outside control panel to shut down TP-6102A in an emergency?
Pull E-STOP Button to shut down TP-6102A Turbine in the case of an emergency
What is unique about the EBV installation for MP-6102 and TP-6102A?
The EBV’s are equipped with a Manual Override, a hydraulic hand pump used to open the valve in an emergency
State the purpose of the Crude 2 Desalters.
To remove water, salts, and solids from incoming crude feed for corrosion, scale and fouling control so as to maintain heat exchanger efficiencies
What salt is primarily removed in the Desalters?
Sodium Chloride
What compound is formed in the furnace tubes if chloride salts are not removed from the feed in the Desalters?
Except for Sodium Chloride, chloride salts decompose into HCL in the furnace tubes
HCL forms hydrochloric acid in C-6101 and C-6102 overhead systems by combining with what?
HCL combines with water (steam) in C-6101 and C-6102 to form hydrochloric acid
Hydrochloric acid corrodes C-6101 and C-6102 overhead systems
Where is the biggest problem from Sodium Chloride noted if not removed from the crude feed?
Sodium Chloride, NaCl, tends to carry through to the residuum stream to become a fouling threat to downstream equipment and process units
Describe normal Desalter operating temperature and pressure
Temperature: 260 – 305 Degrees F, Max 320 Degrees F
Pressure: 240 – 260 PSIG
List the sources of Crude 2 Desalter wash water
D-6106 Seal Drum, 27 Plant Phenolic Water, 84 Plant, Seal Drum Condensate
Why is wash water directed to D-6125B first?
D-6125B has cleanest water available for reuse because D-6125A Desalter sees dirty crude first
