초록 ▼

High purity nitrogen from an air separation membrane/deoxo system is dried in a membrane dryer unit preferably operated with a countercurrent flow path in the membrane bundle. Drying is enhanced by the use of purge gas on the permeate side of the membrane dryer unit, with feed air, product nitrogen

High purity nitrogen from an air separation membrane/deoxo system is dried in a membrane dryer unit preferably operated with a countercurrent flow path in the membrane bundle. Drying is enhanced by the use of purge gas on the permeate side of the membrane dryer unit, with feed air, product nitrogen or waste gas from the air separation membrane system being used as purge gas.

대표청구항 ▼

An improved process for the production of dry, high purity nitrogen from air in which an air separation membrane system is used to produce purified nitrogen from feed air for passage to a catalytic combustion system for reaction of residual oxygen with hydrogen, the residual wet, high purity nitroge

An improved process for the production of dry, high purity nitrogen from air in which an air separation membrane system is used to produce purified nitrogen from feed air for passage to a catalytic combustion system for reaction of residual oxygen with hydrogen, the residual wet, high purity nitrogen stream being cooled and passed to condensate removal means prior to drying, the improvement comprising: (a) passing said wet, high purity nitrogen stream from an air separation membrane system in which it is produced from feed air to a membrane dryer unit capable of selectively permeating water present therein; (b) recovering dry, high purity nitrogen product gas from the membrane dryer unit as non-permeate gas; (c) withdrawing water vapor as the permeate gas from the low pressure permeate side of the membrane dryer unit; (d) passing a relatively dry purge gas to the low pressure permeate side of the membrane dryer unit to facilitate the carrying away of water vapor from the surface of the membrane and maintaining the driving force for removal of water vapor through the membrane from the high purity nitrogen stream for enhanced moisture separation therefrom, said relatively dry purge gas comprising waste gas from said air separation membrane system, feed air of nitrogen product gas, whereby the passage of purge gas on the permeate side of the membrane dryer unit enables the desired moisture removal to be achieved with minimum loss of desired nitrogen product gas.