| 摘要 |
<p>PURPOSE:To increase an amount of separated and recovered liquid nitrogen (LN2) to a value higher than that of liquid oxygen (LO2) and to reduce consumption of a power caused by the separation of liquid by a method wherein a heating means to vaporize a nitrogen component in liquid raw material air is mounted to the bottom part of a lower tower, and the lower tower is connected to a main heat exchanger so that raw material air cooled by the main heat exchanger is fed to a position at a stage higher than that of the heating means of the lower tower. CONSTITUTION:In a lower tower 41, by heating raw material gas fed to the lower tower 41 by means of flush gas from a reboiler 44, the raw material gas is separated into N2 and mixture liquid of O2 and Ar substantially not containing N2. This separation enables an approximate whole amount of N2 contained in the raw material gas to be taken out as a product LN2 and reflux LN2. This constitution enables the increase of the product LN2 capable of being separated and recovered.</p> |
