Nitrogen (Industrial processes)

Question 1

Describe the cryogenic process

Answer 1

Filtered air is compressed in a centrifugal compressor and then cooled
Liquid water is separated out from air
As the air cools, moisture is first condensed and frozen on the wall of the heat exchanger passage
At these lower temperatures carbon dioxide also freezes and is deposited on the walls of the heat exchanger
The air emerging from the heat exchanger is completely dry and 99% of the carbon dioxide is removed
The clean air is fed to the bottom of the column
The double column rectifier consists of two distillation columns
The columns are connected through the heat exchanger which serves as a condenser for the lower column and a re-boiler for the upper column
Nitrogen will ascend and Oxygen will descend
The condensed nitrogen is split as it leaves the main condenser, one portion goes to the lower column as reflux and the other goes to the upper column
Liquid oxygen leaves the bottom of the lower column
Nitrogen is removed as saturated vapour from the upper column

Question 2

State the uses of Nitrogen gas

Answer 2

1.Food preservation – Used to displace oxygen in food packaging to prevent spoilage and oxidation
2.Inert atmosphere for industrial processes
Cryogenics – In its liquid form, nitrogen is used to flash freeze food, store biological samples (like sperm, eggs, and vaccines), and in cryotherapy
3.Tire inflation – Used in aircraft and racing car tires because it’s more stable than air
4.Chemical manufacturing – Used in the production of ammonia (NH₃) through the Haber process, which is crucial for fertilizers.
5.Used as tertiary oil recovery
6.Used as a gaseous blanket to obtain extremely low temperatures

Question 3

What is the chemical property of Nitrogen gas?

Answer 3

It is not reactive as a result of the strong bonding forces between N atoms in the molecule.