Module 1 Flashcards
Typical Distillation curve
- Butanes (LE)
- Gasoline
- Naptha
- Kerosene
- Gas Oil
Salts are (2)
- naturally occurring in crude oil
2. water soluble
Crudes Salts (3)
- Magnesium Chloride
- Sodium Chloride
- Calcium Chloride
First step of crude oil seperation
washing in the desalter (with water)
What comes out of the desalter?
salt, mud , sand
Undermixing in the desalter result in
salt carryover downstream
What happens to the salts in the crude furnance?
Hydrolyzes (breaks apart and forms HCL)
Which crude salt hydrolyzes most / least?
MOST = magnesium Chloride Lease = Sodium Chloride
Where is naOH injected to form Sodium Chloride
downstream of the desalter
Dry CL is
not corrosive
Wet CL is
corrosive
wash water outlet monitors (3)
- ph
- iron
- chlorides
what are naturally occurring in crude oil (2)
Sulfer / N2
Adding heat converts sulfur to
H2S (corrosive/poisonous)
sulfur/n2 increases with
Molecular weight
N2 becomes an issues
- in feed produce cyanide
2. in hydrotreating N2 combines with H2 and form NH3 (ammonia) and form ammonia bisulfide with HCL
Fluidized Catalytic Cracking Unit (FCCU) & Delayed Coker Unit (Coker) purpose?
Crack large molecules (Asphalt) into small usable molecules (gasoline/diesel)
- FCCU = catalyst
- DCU = thermally
Purpose of Hydrotreating is to remove
sulfur / N2
purpose of sour water stripper (SWS)
remove H2S
where does rich amine goes to?
Amine Unit
heavier MW = need more ___ and higher ____
Hydrogen and higher pressure
heavier MW = need more ___ and higher ____
Hydrogen and higher pressure , and more sulfer / N2
where does rich amine goes to and do what?
Amine Unit -> remove H2s
Hydrotreating Steps
- Hydrogen (H2) is combined with hydrocarbon.
- H2 combines with the Sulfur (S) in the hydrocarbon.
- H2S (a gas) is formed.
- The H2S gas and the liquid hydrocarbon are separated.
- H2S gas goes to an Amine Treater where the H2S is transferred to the amine and recovered.
reactor effluent air coolers damage mechanism
- Wet H2S
- Ammonium Bisulfide
- Ammonium Chloride
- HCl corrosion
- Erosion
- Chloride
is amine a acid or a base?
base
is amine a acid or a base?
base
purpose of a Alkylate unit
Combine cracked gasses (from either FCCU or Coker) to form large gasoline molecules.
Catalyst in a Alkylation (2)
Sulfuric Acid or Hydrofluoric HF Acid
Alkylation / HF Construction – Primarily ____ when (2)
Carbon Steel CS is fairly resistant to corrosion by either Sulfuric Acid or HF Acid when the
- acid concentration is high and
- velocities are low.
Independent of the type of catalyst used in an Alkylation unit, what is one of the key parameters to controlling the corrosion rate in such a unit?
Temperature
amine treating system, what vessel operates at a higher temperature?
Amine Regenerator
amine treating system, what vessel operates at a higher temperature?
Amine Regenerator
Catalytic Reforming unit (CRU) bi products (2)
- high octane (100%)
2. hydrogen H2
control parameter for a desalter (3)
- amount of mixing
- water %
- temperature
desalter does not remove
sulfer
function of the Tank Farm in a refinery?
Remove solids from the crude oil
Dewater the crude oil
Blend the crude oil for the desalter
function of the Tank Farm in a refinery? (3)
Remove solids from the crude oil
Dewater the crude oil
Blend the crude oil for the desalter
Is amine water soluble, or hydrocarbon soluble?
water
n what part of the hydrotreating process do most of the ammonium salts form corrosive liquid salts?
Reactor Effluent Air Coolers
the corrosion rate of bare metal decreases with time. This is because:
The passive layer protects the metal from further corrosion.
Low-alloy steel contains
about 1%-5% of alloying elements.
Most carbon steels used in a refinery contain how much of the alloying element carbon (C)?
0.15 – 1.0 %
What alloying element in Cast Iron makes it difficult to weld?
Carbon (C)
The most common acid gases found in the refinery and petrochemical plants are (2)
).
H2S (Hydrogen Sulfide) and CO2 (Carbon Dioxide
