Oxygen is the most important gas in Earth’s atmosphere because it is absolutely essential for respiration. No life is possible without the existence of oxygen. All living beings breathe O2 in the atmosphere which is constantly replenished by the plants through a process known as photosynthesis. Now it has become popular to use indoor oxygen plants such as Aloe Vera plant, Pathos plant, Spider plant, Areca Palm, Snake plant, Tulsi, Bamboo plant and Gerbera Daisy for purifying polluted air we breathe. And, the industrial machinery designed to separate oxygen from other gases from other gases using industrial processes such as pressure swing adsorption (PSA) and cryogenic distillation is also called oxygen plant. It is used for generating oxygen with purity ranging from 95% to 99.7% depending on use.
PSA plant oxygen production
PSA oxygen plant uses the adsorption technology using twin towers filled with adsorbent material Zeolites. The PSA plant is made up of the following components: adsorbent containers, oxygen analyzer, PLC, valves and a tank. When the ambient air goes through one of the towers containing molecular sieves filled with Zeolites where nitrogen and carbon dioxide gets adsorbed allowing oxygen to pass through and is collected as a product gas. At fixed intervals of time, the active tower is switched to regeneration mode evaporating the adsorbed gas back into the atmosphere. In this PSA process, oxygen purity is monitored.
Cryogenic oxygen plant
In the cryogenic process the ambient air is taken into the air separation unit where it is filtered and compressed. Then, the air is passed into purification unit where the impurities present in the air such as carbon dioxide, moisture and hydrocarbons are removed. Afterwards, the process air is moved through a series of heat exchangers cooling it to cryogenic temperature. After the liquefaction of the air, it is passed through high pressure distillation column separates oxygen from nitrogen and other gases based on their boiling points. Now the separated gas, oxygen is sent into a lower distillation column where it is distilled to required purification level.
