Oxygen gas and its usage in Steel Plant...

Oxygen gas and its usage in Steel Plant Oxygen is an active, life sustaining component of the atmosphere. The percentage of oxygen in air is 20.94 % by volume or 23 % by weight of the air. It is the most widely occurring element on the mother earth.  Because it forms compounds with virtually all chemical elements except the noble gases, most terrestrial oxygen is bound with other elements in compounds such as silicates, oxides, and water. Oxygen is also dissolved in rivers, lakes, and oceans.  Molecular oxygen occurs almost entirely in the atmosphere. Between 1770 and 1780, Swedish pharmacist Carl Wilhelm Scheele, British clergyman Joseph Priestley and French chemist Antoine Laurent Lavoisier researched, documented and helped discover oxygen. The name oxygen was first used by Lavoisier in 1777. It was only later that its high level of chemical reactivity was discovered. Oxygen is produced in large quantities and at high purity as a gas or liquid through the liquefaction and distillation of ambient air at the cryogenic air separation plants. It is also produced on commercial scales as a lower purity gas (typically about 93 %) by adsorption technologies (pressure swing adsorption (PSA), or vacuum-pressure swing adsorption (VPSA or VSA). Very pure oxygen can be produced by the electrolysis of water. Gaseous oxygen is called in short as GOX while the liquid oxygen is called in short as LOX. Liquid oxygen is a cryogenic liquid. Cryogenic liquids are liquefied gases that have a normal boiling point below – 150 deg C. Liquid oxygen has a boiling point of -183 deg C. Because the temperature difference between the product and the surrounding environment is substantial, it is necessary to keep the liquid oxygen insulated from the surrounding heat. Oxygen also requires special equipment for handling and storage....

Cryogenic process of Air Separation Jul20

Cryogenic process of Air Separation...

Cryogenic process of Air Separation   Dry air contains by volume 78.08 % of nitrogen, 20.95 % of oxygen, and 0.93 % of argon along with traces of a number of other gases. Ambient air may contain varying amount of water vapor (depending upon humidity) and other gases produced by natural processes and human activities. Air separation plants are used for the production of nitrogen or/and oxygen as gases and sometimes as liquid products. Some plants also produce argon.  All air separation plants employ either non cryogenic based technologies or cryogenic based technologies. Non cryogenic air separation plants produce gaseous nitrogen or oxygen products using near ambient temperature separation processes. These plant produce oxygen which is typically 90 % to 95.5 pure or nitrogen which is typically 95 5 to 99.5 % oxygen free. Cryogenic air separation plants are most commonly used to produce high purity products at medium to high production rates. They can produce products as gases or liquids. This technology is based on difference in boiling points of gases. All air separation processes start with compression of air. The cost of electric energy is the largest single operating cost incurred in air separation plants. It is usually in the range of one third or two thirds of the operating costs associated with producing gas and liquid products. Cryogenic plants Cryogenic plants are based on cryogenic air separation processes.  The basic process was commercialized early in the 20th century. Since then, a large number of process configuration variations have emerged, driven by the desire to produce particular gas products and product mixes as efficiently as possible at various required levels of purity and pressure. These air separation process cycles have evolved in parallel with advances in compression machinery, heat exchangers, distillation technology and gas expander technology....