What are the processes involved in liquid nitrogen equipment?

　　Liquid nitrogen generator equipmentWhat is it?

　　The low-temperature air separation nitrogen of liquid nitrogen generator equipment is a traditional nitrogen production method with a history of nearly decades. Using air as a raw material, through compression, purification, and heat exchange, the air is liquefied into liquid holes. Liquid holes are mainly a mixture of liquid oxygen and liquid nitrogen. Because liquid oxygen and liquid nitrogen have different boiling points, nitrogen is obtained through rectification separation of liquid holes.

　　Liquid nitrogen generator equipmentWhat are the processes?

　　Low-temperature nitrogen can not only produce nitrogen gas but also liquid nitrogen, meeting the process requirements for liquid nitrogen. It can be stored in a nitrogen storage tank. During nitrogen intermittent load or small maintenance of air separation equipment, the liquid nitrogen in the storage tank can be sent to the product nitrogen pipeline after heating in the vaporizer to meet the nitrogen demand of the process device. The working cycle of low-temperature nitrogen (the interval between two major heatings) is generally more than one year, so low-temperature nitrogen is generally not considered for backup. Pressure swing adsorption nitrogen can only produce nitrogen and has no backup means, and a single set of equipment cannot guarantee continuous long-term operation.

　　What is the purity of liquid nitrogen generator equipment?

　　Low-temperature nitrogen can produce nitrogen with a purity of 9.999%. Nitrogen purity is limited by nitrogen load, number of plates, plate efficiency, liquid air oxygen purity, etc., and the adjustment range is very small. Therefore, the product purity of low-temperature nitrogen equipment is basically constant and is not easy to adjust. The purity of nitrogen made with pressure swing adsorption is generally in the range of 95%-99.9%. If higher purity nitrogen is needed, nitrogen purification equipment needs to be added. Nitrogen purity is only affected by the product nitrogen load. If other conditions remain unchanged, the greater the nitrogen emission, the lower the purity of nitrogen. Conversely, higher. Therefore, in the case of pressure swing adsorption nitrogen equipment, as long as the load ensures product purity, it can be adjusted arbitrarily between 90%~99.9%.

　　Low temperatureLiquid nitrogen generator equipmentWhat are the characteristics?

　　1) Low-temperature containers and pipelines such as low-temperature heat exchangers and distillation columns are placed in a freezer, filled with a low thermal conductivity insulation layer to prevent ambient heat from entering and reduce cold loss; otherwise, the equipment will not work properly.

　　2) The materials used to make low-temperature equipment need sufficient strength and toughness at low temperatures and good welding and processing properties. Commonly used materials include aluminum alloys, copper alloys, and stainless steel;

　　3) Boiling impurities in the air (such as moisture and carbon dioxide) must be removed in advance at room temperature. Otherwise, the channels in the equipment will be blocked, and the equipment will not work properly.

　　4) Acetylene and hydrocarbons in the air will accumulate to a certain extent after entering the air separation column, affecting safe operation and may even cause explosions. Therefore, purification equipment must be installed to remove them.

　　5) For sealed containers storing low-temperature liquids, if the outside is heated, some low-temperature liquid will absorb heat, vaporize, and the pressure will automatically increase. To prevent excessive pressure, a reliable safety device must be installed.

　　6) After low-temperature liquid seeps into the foundation, the foundation will freeze, and the equipment will tilt. Therefore, the sealing of equipment, pipelines, and valves must be ensured, and the stress and deformation caused by thermal expansion and cold contraction must be considered. 7) Porous organic materials such as wood and coke immersed in liquid oxygen will burn violently when they contact a garden or are subjected to a certain impact. Therefore, porous organic materials are not allowed in the freezer. For liquid oxygen discharge, professional liquid oxygen discharge pipes and containers must be considered in advance, and they cannot be channeled.

　　8) When low-temperature liquid impacts carbon steel plates for a long time, the steel plates will become brittle. Therefore, carbon steel products cannot be used for pipelines and discharge ports that discharge low-temperature liquids. 9) Nitrogen and manganese are asphyxiating gases, and their liquid discharge pipes should be drawn outdoors. The gas discharge pipeline must have a certain discharge height, and the discharge port cannot face the platform stairs.

　　10) Oxygen is a strong oxidizing agent, and its discharge pipe cannot be directly discharged into a poorly ventilated factory.