Liquid nitrogen is an inert, colorless and odorless gas.It is non-corrosive, non-flammable.This gas is a big part of the atmosphere (78.03% of the total).Although liquid nitrogen and will not support combustion, however, it is inert, except in those cases where it is heated to very high temperatures, which is connected to some of the most active metals such as lithium, magnesium.Consequently, the compounds of nitrides are formed.It can also interact with oxygen, thereby forming oxides of nitrogen, nitrogen in combination with hydrogen in the presence of catalysts - ammonia.
Production of liquid nitrogen in an industrial environment
Nitrogen liquid and a gas is obtained the same way - from the air.In laboratories it is produced during the decomposition of ammonium nitrite.This reaction is exothermic.That's why it goes with the release of 80 kcal (335 kJ) of energy.For liquid nitrogen cooling vessel is required, although the start of the reaction requires heating.Also, the molecular nitrogen in the industry was prepared by fractional distillation of liquid air atmosphere.This method can also be obtained "atmospheric nitrogen."All the ways in which to seek liquid nitrogen, are aimed at creating a safe and clean products for industry, medicine and household products
Impact on human health
Although liquid nitrogen is non-toxic and inert, it can trigger choking person as may displaceoxygen in the air below the level needed to sustain life.Inhalation of nitrogen in excessive amounts can cause dizziness, nausea, vomiting, loss of consciousness and death.Death can result from loss of orientation and consciousness that may interfere with the self-evacuation of the contaminated area.At low oxygen concentrations unconsciousness and death may occur in seconds.Personnel, including rescue workers, must not enter the premises without SCBA or respirator, if the oxygen concentration below 19.5%.
If liquid nitrogen, then it is stored in special containers.This is in order to protect others from the effects of the interaction with the element.The liquid nitrogen is kept at a pressure of up to 350 MPa in the container volume of from 80 to 450 liters.
Liquid nitrogen - storage and use
Store and use this product should be only in rooms with good ventilation.It absolutely can not be stored in an enclosed space.Preparation of liquid nitrogen in the laboratory and requires special methods for its storage in containers.Cryogenic containers are equipped with special devices for pressure relief and control of internal pressure.Under normal circumstances, they are safe.In no case can not include, delete, or enter into any other interaction with the pressure-relief device.It is impossible to liquid nitrogen hitting the unprotected parts of the body.
containers that store liquid nitrogen should be used and stored in an upright position.Do not dispose of the containers, store them on their sides.You also can not independently dispose of the vessels containing the substance.If you have difficulty operating the container or valve, then stop using it immediately.
Personal protective equipment (PPE)
you should definitely familiarize yourself with the purpose of the security properties of liquid nitrogen before use.We must protect the eyes and the most sensitive parts of the body from the vapor of the cryogenic liquid.Production of liquid nitrogen in the laboratory and its use implies the existence of personal protective equipment.Must be: a face shield or goggles, loose-fitting leather gloves, long sleeve shirt and pants without cuffs, also need safety shoes, especially for those who produce container handling.Respiratory must also be protected with special masks.
