Liquid air separation equipment is an air separation device that directly produces liquid oxygen, nitrogen and other liquid products. Some liquid air separation equipment not only produces liquid products, but also produces a small amount of gas products.
According to the methods of obtaining liquid products, there are two kinds of liquid air separation equipment: one is to produce gaseous oxygen and nitrogen, and then convert gaseous products into liquid products through liquefaction device. The other is to produce liquid oxygen nitrogen and other products directly with liquid air separation equipment.
According to the pressure level, the liquid air separation unit can be divided into two categories: low pressure circulating liquid air separation and medium pressure circulating liquid air separation: low pressure circulating gas expansion is small, working pressure is low, and gas liquefaction is realized through phase change. In order to obtain cooling capacity, the circulating air quantity should be greatly increased, and the corresponding energy consumption will be greatly increased; while the medium pressure circulation has high working pressure and liquefaction temperature, The cooling capacity required for unit gas liquefaction is correspondingly reduced. Instead of isothermal condensation process, gas liquefaction is directly transformed into liquid, thus reducing the circulating gas volume and greatly reducing the energy consumption.
Generally, for air separation equipment with liquid product less than 1000m3/ h, the process flow of liquid air separation with full low-pressure air circulation is adopted; when the output of liquid product is required to be more than 2000-3000m3 / h, the process flow of liquid air separation with medium pressure refrigeration circulation is adopted.
In addition, the liquid air separation equipment manufacturers will also design the process flow of the liquid air separation unit and the configuration and organization of the monomer equipment according to the requirements of the liquid oxygen and nitrogen product users for the product purity and output.
