petroleum refining study

Petroleum refining Study

• Crude Oil components

• Refinery Flowchart

• What is done in refining

What is Crude Oil?

• Mixture of organic

carbon chain

molecules

• Impurities include

sulfur and nitrogen

compounds

• Some metals and

salts too

Crude oil components

Cycloparaffin hydrocarbons in which all of the available

bonds of the carbon atoms are saturated with hydrogen

are called naphthenes. Typical examples of these are

cyclopentane, cyclohexane, etc.

Aromatic hydrocarbons contain a benzene ring which is unsaturated but very stable and frequently behaves as a saturated compound.

In refining, oil is processed

1.To reduce to a pure component

state, to remove impurities

2. To improve or perfect

3. To make blended products with end

use.

Processes in a Refinery. . .?

• Separation of components by distillation, e.g.:

Atmospheric

Vacuum

Hydrotreating (uses excess hydrogen)

• Breaking apart molecules to make smaller ones, e.g.:

catalytic cracking

hydrocracking

• Joining molecules to make bigger ones, e.g.:

Reforming - alkylation that lengthens the hydrocarbon chain

Reforming - cyclic that generates hydrogen

Fractionation utilizes a mass separation technique

called distillation in which the feedstock is distilled into

various cuts of target boiling ranges or even separated

into individual hydrocarbon compounds.

Distillation is accomplished by imposing a temperature

profile across the tower enabling differences in the

equilibrium compositions of the vapor and liquid phases

to change the compositions throughout the distillation

tower.

The refinery processes include chemical

reactions on the hydrocarbons being

processed. Generally, the reactions are carried

out at elevated temperatures in the 600-

1,000°F range depending on the process, and

in most cases at elevated pressures, from 200

pounds per square inch (psi) to as high as

3,000 psi.

Refinery Process Flow Chart

Dis

tilling

Flasher

Visbreaker

CCU

Alky

Sp

litter

Hydrotreating

Hydrotreating

Isom

Reformer

Gas Plant

Sulfur

Fuel Gas

Gasoline

Jet Fuel

Distillate Fuel

Residual

Fuel Leffler, 1985

Other Refinery Units

• Steam Generation

• Wastewater Treatment

• Hydrogen Generation

• Power Generation (e.g., cogen)

• Air Separation Plant

• Loading/Unloading - Railcar, Trucks, etc.

• Storage (high pressure hydrocarbon, crude oil, intermediates)

Floating-Roof Tanks - 150„ diameter is common

Spherical Tanks - 50„ are common

Horton Spheroid (refrigerated)

Steam-Heated Tanks for “Heavier” Products

• Self-Contained Firewater Supply

• Firewater Pumps

Hazardous Materials handled…

• Sulfur

• Hydrofluoric Acid (HF)

• Sulfuric Acid (H2SO4)

• Ammonia (NH3)

• Sodium Hypochlorite

• Radioactive Materials

• Chlorine

• Amines

• MEK

• Sulfur Dioxide (SO2)

• Heavy Metal Catalysts

• Sour Water

• Caustic (fresh/spent)

• Alcohol

• Asbestos

Physical Hazards

• High Pressure/Temperature Steam

• Oil/Gas-Fired Furnaces

• Acoustic

• High Voltage (4160V, 480V, 13.2 kV)

• Falling Hazards

• Confined Space Hazards

• Cranes/Lifting Hazards

• Hot Work Hazards

• Acid Exposure

• Toxic Vapors

• Radiation

• Flammability Hazards

Common PPE Requirements

• Hardhat

• Hardsoled / Hardtoe Shoes

• Safety Glasses with Side

Protection

• Safety Goggles or Faceshield

• Fire-Resistant Clothing

Process Hazards

• Emergency Flare

• Atmospheric Pressure Relief

• High Temperature (up to 2000oF)

• Low Temperature (e.g., Brittle Fracture)

• High Pressure (up to 3000 psig)

• Low Pressure (e.g., vacuum)