Industrial liquid nitrogen

Industrial liquid nitrogen is a colorless liquid formed when nitrogen is cooled to -195.8°C. Nitrogen (usually called inert gas) is used in some inert atmospheres for metal processing and in bulbs to prevent arcing, but it is not chemically inert. It is an essential element in the life of plants and animals, and is a component of many useful compounds. Nitrogen combines with many metals to form hard nitrides, which can be used as wear-resistant metals. A small amount of nitrogen in steel will inhibit grain growth at high temperatures and increase the strength of certain steels. It can also be used to produce hard surfaces on steel. Nitrogen can be used to produce ammonia, nitric acid, nitrate, cyanide, etc.; in the manufacture of explosives; filling high-temperature thermometers, incandescent bulbs; forming inert materials to preserve materials used in drying ovens or glove bags. Liquid nitrogen in food freezing; used as a coolant in the laboratory.

Nitrogen itself is non-toxic. Only when the oxygen pressure is significantly lower, it will show the toxicity of nitrogen. Under the atmospheric pressure of 3.923×106pa (that is, the nitrogen pressure of 3.138pa), the visual, auditory and olfactory stimuli are not sensitive. When producing liquid nitrogen, wear protective gloves and glasses, and ventilate the workshop to ensure safe transportation.