Small air separation units usually refer to low-temperature distillation oxygen production equipment with an oxygen production capacity of ≤ 1000 Nm3/h, widely used in industrial gas supply, medical, laboratory, and small and medium-sized metallurgical and chemical industries.
Production range and product form
Mainly gas products-Oxygen production: 20~800 Nm3/h (standard state: 0 ℃, 101.325 kPa).
-Nitrogen production: usually 1-2 times that of oxygen (such as KDON-1000 model: oxygen 1000 Nm3/h, nitrogen 2000 Nm3/h).
-Typical model:
-KDON-1000: Oxygen 1000 Nm3/h, Nitrogen 2000 Nm3/h;
-KDON-1500Y: Liquid oxygen or liquid nitrogen 1500 Nm3/h;
-KDON-2500Y: Liquid oxygen/liquid nitrogen 2500 Nm3/h (fully liquid form).
Core Process and Technical Characteristics
Low temperature distillation process-Molecular sieve purification: Pre adsorption removes impurities such as H2O, CO2, C2 H2, ensuring distillation safety.
-Double tower distillation: oxygen and nitrogen are separated in the lower tower, purified in the upper tower, and gas-liquid exchange is achieved in the main condenser evaporator.
-Turbine expansion mechanism cooling: The positive reflux expansion process provides cooling capacity with low energy consumption (0.65~1.85 kW · h/m3 per unit of oxygen consumption).
Safety and energy efficiency optimization
-External compression process: compress oxygen at room temperature, easy to operate;
-Internal compression process: Low temperature compression of liquid oxygen for higher safety (avoiding hydrocarbon accumulation).
-Low energy consumption design: All plate heat exchanger and booster expander recover energy, saving 10-20% energy compared to similar equipment.
-No cooling water operation: air-cooled pre cooling system, suitable for water scarce areas.
-PLC control system: (Siemens and other brands), supporting automatic adjustment and fault diagnosis.
-Long cycle operation: The molecular sieve has a long switching cycle, with an operating cycle of ≥ 24 months and a start-up time of 8-24 hours.
-Low noise design: Operating position noise ≤ 85 dB (A).
Application scenarios and selection suggestions
-Industrial gases: synthetic ammonia, methanol, metal smelting (such as KDON-6500 used in metallurgy).
-Medical and laboratory: high-purity oxygen (>99.6%), food grade nitrogen (99.999%).
-Mobile requirements: Skid mounted design, detachable for transportation (such as 50-180 m3/h models).
The small air separation unit has the core advantages of modular design, low energy consumption, and high purity, with a production capacity covering 20-2500 Nm3/h of oxygen. It achieves efficient separation through low-temperature distillation and molecular sieve purification. The selection should comprehensively consider the product form (gas/liquid), purity requirements, and energy consumption indicators, and prioritize the selection of highly-reliable models with full distillation and intelligent control to meet the diverse needs of medical, metallurgical, chemical and other scenarios.
