We can design, manufacture and complete air separation plant according to end users' climatic, geologic and water quality conditions, as well as their different purity and quantity requirements for oxygen, nitrogen and argon. Features: 1) The process is a sort of wholly low-pressure refrigeration recycles; high efficiency turbo expander is adopted to refrigerate and adjustable nozzle is used to adjust refrigeration amount 2) High efficiency isothermal turbo air compressor, gas cooler and water separator are adopted; the whole unit is with high isothermal efficiency, less energy consumption and reliable running 3) Aluminum plate fin heat exchanger is adopted, which is with compact structure, low flow resistance and high heat transfer efficiency 4) Adopts molecular sieve purification system, and the production ratio between O2and N2 is 1:2.5, with simplified process, less matching equipment, and easier erection and operation 5) The DCS system can be adopted according to end users' requirements to realize automatic control and reduce power consumption