method and apparatus for the production of air gases by cryogenic separation of air with variable liquid production and energy use

摘要

A method and apparatus for the production of air gases by cryogenic air separation may include the steps of sending a purified compressed air flow into a cold box under conditions effective to cryogenically separate the air flow into oxygen and nitrogen using a speaker system wherein the purified compressed air flow is at a supply pressure when entering the speaker system; extract oxygen at a product pressure, supply oxygen at a supply pressure for an oxygen pipe, where the oxygen pipe has a pipe pressure; and monitor piping pressure. The method may also include a controller configured to determine whether it operates in an energy saving mode or a variable liquid production mode. By operating the method in a dynamic manner, additional high value cryogenic liquids and / or energy savings can be realized in cases where the piping pressure deviates from its highest value.