摘要 |
<p>This invention makes possible a substantial improvement in the distillation column efficiencies of a cryogenic air separation process while still retaining high reboil rates through the argon stripping section of the low pressure column. Those advantages result in a lower energy requirement for separating air while still yielding medium to high oxygen purity. In a triple pressure column arrangement, the medium pressure column efficiency is increased by reboiling it at two or more locations by latent heat exchange with both the high pressure and low pressure columns. The LP column vapor which reboils the MP column is taken from above at least part of the argon stripper, to maintain a high reboil rate through the stripper.</p> |