Safety of Dewar Liquid Nitrogen Storage Tank

Liquid nitrogen is an ultra-low temperature substance with a temperature of up to -196°C. It is a colorless, non-toxic, and odorless liquid, mainly derived from nitrogen in the air, which is compressed and liquid after separation. It is because of its ultra-low temperature, wide source and chemical inertness, it is widely used in various industries and fields such as industry and agriculture, medicine, chemical and chemical industry, food, aerospace, military, etc., and it is also frequently used in the testing of our large instruments. However, because liquid nitrogen is a dangerous chemical, improper operation will also cause the explosion of the liquid nitrogen container and cause a certain loss. Therefore, you need to be very careful in transportation and use.

 
Selection of liquid nitrogen container
The commonly used liquid nitrogen containers in the laboratory include steel bottles, liquid nitrogen storage tanks and Dewar flasks. Steel cylinders are generally made of seamless carbon steel and alloy steel, and are suitable for gas with medium pressure below 150 atm. Generally speaking, the liquid nitrogen storage tank refers to a liquid nitrogen biological container at normal temperature and pressure, which is mostly made of aluminum or stainless steel.

 

Welded insulated gas cylinders, commonly known as Dewar cylinders, are a kind of multi-layer vacuum insulated mobile cryogenic liquid container invented by Mr. Dewar, which refers to high-pressure or medium-pressure, self-pressurizing and other pressure liquid containers, which are cryogenic liquids The main storage device is widely used in the fields of liquefied gas production, storage, transportation and use. Generally speaking, the liquid nitrogen tank is also a multi-layer insulated container, which can store both liquid nitrogen and samples, while the Dewar can not store samples, only liquid nitrogen, liquid argon, liquid oxygen and carbon dioxide Wait for non-flammable, explosive and toxic low-temperature gas. In actual use, the type of Dewar should also be selected according to the needs.
 
Relatively speaking, Dewar has many advantages: large storage capacity, low pressure, good safety, and simple and reliable operation; clean bottle body, high supply gas purity; high gas utilization rate, long holding time, less waste of gas than steel cylinder ; It has automatic boost control, built-in carburetor, high integration; does not require any kinetic energy, and is not affected by power outages, water cuts and other factors.