Oxygen is the most widely distributed element in nature, accounting for 48.6% of the earth's crust, and it is the most abundant element. Oxygen is needed for hydrocarbon oxidation, wastewater treatment, rocket propellant and breathing of animals and people in aviation, aerospace and diving.
Animal respiration, combustion and all oxidation processes (including the decay of organic matter) will consume oxygen. However, the oxygen in the air can be continuously supplemented by photosynthesis of plants.
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Metal cutting and welding. Oxygen with a purity of 93.5%~99.2% is mixed with combustible gas (such as acetylene) to produce a flame with extremely high temperature, thus melting the metal.
The metallurgical process is inseparable from oxygen. Oxygen is also needed to strengthen the production process of nitric acid and sulfuric acid. Blowing the mixture of oxygen and steam into the gas producer instead of air can obtain high calorific value gas. Medical gas is extremely important.
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