310204i Production and Processing Plants Flashcards
Define cracking
Cracking is the process of breaking hydrocarbon molecules into smaller molecules
What is an Olegin Gas?
Gases such as Ethene and Ethylene that are used for the manufacture of other chemicals
Define Coke, as it relates to the refinery process
A carbon-based solid that can be used as heating fuel in the metals and ceramic industries and for the production of graphite electrodes use in electric arc furnaces
It is a byproduct of the coking process
What is Naphtha?
A flammable liquid mixture of similar hydrocarbons from C5 to C12
Naphtha is used as feedstock for producing high-octane gas, and in other commercial uses.
Name the type of solvent that is widely used for acid gas removal.
Amine solvents
Which process converts hydrogen sulfide (H2S) to elemental sulfur in one step?
The Sulferox Process
H2S comes into contact with an iron solution in a contactor and the reaction produces elemental sulfur
Which gas sweetening method does not use an H2S solvent
Molecular Sieve gas sweetening
A column containing adsorbent material that selectively adsorbs mercaptans and acid gases while allowing purified hydrocarbons to pass through
Define adsorption
Adsorption is when atoms, ions, or molecules from a substance adhere to a surface of the adsorbent
What is the purpose of the Claus process
Extracts elemental sulfur from hydrogen sulfide (sour gas)
What happens to the Claus unit tailgas so it can be treated with amine solvent?
The sulfur in the tailgas is converted back to hydrogen sulfide
What are the 4 hydrocarbons that make up the bulk of natural gas?
- Methane CH4
- Ethane C2H6
- Propane C3H8
- Butane C4H10
Which hydrocarbon in natural gas is fuel gas?
Methane CH4
In modern gas plants, what type of equipment is used for natural gas liquid (NGL) extraction?
Cryogenic equipment
Why are the components of natural gas referred to as liquids or gas liquids?
Because at underground pressures, they are liquids, but at atmospheric pressures, they convert to gases
What are the 2 methods used to remove water from the gas stream?
- Glycol dehydration - lean glycol and wet gas are fed into a high pressure contractor where the glycol absorbs water from the gas
- Temperature swing adsorption - wet gas passes through columns filled with adsorbent material called a dessicant. The dessicant absorbs the water while letting the gas pass through. Heated dry purge gas drives the moisture out and regenerates the column.
Why must the catalyst be regenerated in a fluid catalytic cracking (FCC) process?
The shortage of hydrogen atoms in the process results in the formation of Coke, which covers the catalyst. The catalyst must then be removed
Why is vacuum fractionation used in refineries?
The process uses lower temperatures, which prevents thermal cracking.
What type of cracking does a visbreaking process perform?
Mild form of thermocracking
Name three primary treatments used in heavy oil upgraders.
- Thermal conversion - carbon rejection process, bitumen or feed is heated and cracked hydrocarbons exit the coker (delayed coker or fluid coker) as gas vapours
- Hydroconversion - hydrogen addition process, heavy feedstock is cracked in the presence of hydrogen, takes place under high pressure and temperature within an ebullated bed hydrocracker
- Thermal cracking - thermic method to break larger molecules into smaller one, high pressures, generated syn gas which is used to generate steam for SAGD extraction
How are oil upgraders distinguished from each other?
By the primary method of treatment
What byproduct is produced by a carbon rejection cracking process?
Coke
Which upgrader type uses hydrogen addition cracking
Hydroconversion
