How oxygen is made artificially

Oxy­gen is a gas with­out smell or col­or. it's the sec­ond most com­mon gas on the plan­et af­ter hy­dro­gen. it's a robust ox­i­diz­ing agent and a chem­i­cal­ly ac­tive non-met­al. This gas was dis­cov­ered by sev­er­al sci­en­tists at identical time within the eighteenth cen­tu­ry, and therefore the 1st sci­en­tist to ob­tain oxy­gen was the Swedish chemist Scheele in 1772. The French chemist Lavoisi­er con­duct­ed re­search into the el­e­ment, and gave it the name of "oxygène".

 

How oxygen is made artificially

A whole procedure is like this first air is sucked inside a compressor there is a filter before that so that there are no impurities and dust particles if you look inside the compressor there are two valve the inlet valve sucks air inside and then with the help of piston air is compressed  to very high pressure the compressed air then release to the discharge valve. One thing you have to understand that when air is compressed it heats up because when pressurise a gas by compressing inside a container you're putting all those molecules into a smaller volume of space and you are adding potential energy by the compression. Then when you release that gass to atmospheric pressure that energy has to go somewhere. So it's given in the form of heat that means the air that release through the discharge  valve is warm air. Now this warm compressed air needs to be cooled for that it is passed through the freezing unit and that is done with the help of liquid nitrogen liquid nitrogen is very cold it can freez any thing instantly here you have to understand that liquid nitrogen is not mixed with compressed air rather they discharge pipe which the compress air flow outs that pipe is covered with coil tubing liquid nitrogen is then spremed into the coil tube which is in direct touch with discharge valve through which compressed air is flowing out after in coming touch with liquid nitrogen the compress air become cold the temperature falls down up to -200 degree Celsius the cold compress air then send to separator here carbon dioxide is separated as dry ice. The air now free from carbon dioxide then send through a expansion turbine the air is now allows to expand here the air turns into a liquid it is called liquified air it's temperature is around -200 degree Celsius. In the end liquid air is send into an air distillation column where it is slowly warmed up because then it seprate various components of air like nitrogen Argon and oxygen etc. As you know air is mixture of different gases so in this air distillation column different gasses that is present in the air separated by slowly warming by the liquified air nitrogen get separated first because nitrogen boils at -196 degree Celsius after that Argon get separated argon boils at -186 degree Celsius oxygen which has a higher boiling point is left behind and it's collected separately 

Now please don't get confuse - 196 is much more coller than -185 oxygen boils around -182  to -185 degree Celsius so if you look into this three temprature obviously -185 is higher against two means oxygen have the higher boiling point at the bottom of the air distillation column you will see liquid oxygen settles down. Argon gas is sold for industry use particularly in iron and steal industry for Belding. Nitrogen gas is used to make fertilizers and food pakaging industry so basically from entire process in the end you get liquid oxygen the liquid oxygen is transported by filling into the special containers such as aluminium cylinders if it requires in larger quantities then cryogenic liquid oxygen cylinder is used so always remember the oxygen for industrial use us delivered to customer in liquid form and they are store in cylinders and tanks at high pressure it is said that pressure at which liquid oxygen is stored in container is upto ~3000 PSI/200 Bar for those of you who don't know what is 3000 PSI. PSI is unit of pressure expressed in pounds of force per square inch of area in laymen terms anything more the 1000 PSI is a lot of pressure. Any how liquid oxygen is stored in the cylinders at around 3000 PSI. This cylinders comes with pressure regulators that allows you to set the output pressure. A patient in hospital needs around 50 PSI which allows slow supply of oxygen.

Sizes of oxygen cylinder

Oxygen cylinder comes in different sizes and can be heavy the largest size is around 1.5 meters (60 inches) tall, 60 kg and contain 7800 litres of liquid oxygen 

Today a patient in hospital required 130 litres of oxygen per minute that means a large cylinder would last about an hour

Cryogenic cylinder 

Now we talk cryogenic cylinders they comes in different capacities that is 3016 litres to 61620 litres. Reason this cylinders called cryogenic tanks. The term cryogenic (term used in physics) any thing that is produced or stored below the temperature of -150 degree Celsius to absolute zero this absolute zero is refere to temprature -270 degree Celsius the reason it called absolute zero because no object is cooled below -270 degree Celsius because it is believe that no heat energy left in the substance below this temprature as per the law of thermodynamics absolute zero can not be reached.

Any how the meaning of cryogenic is any thing that produced or store bellow the temperature of -150 degree Celsius. Since liquid oxygen is form at -185 to -182 degree Celsius that is why this large oxygen cylinders are named as cryogenic Oxygen tanks.