| 摘要 |
<p>The oxygen-free pressurized nitrogen fraction is released into the low pressure column which is heated in its sump. In the low pressure column, raising vapors form and by means of a cycle ultrapure nitrogen from carbon monoxide is released at the top of the low pressure column, carbon monoxide-free head-gas is removed at the top of the low pressure column and partially liquefied at raised pressure. The liquefied portion is released in He-Ne-He-column which is heated in its sump, and the ultrapure nitrogen is removed as liquid. The oxygen-free pressurized nitrogen fraction is drawn either from an upper portion of the pressure column liquid or ready in a liquid tank with stored oxygen-free nitrogen. Process for producing ultrapure nitrogen is by means of low temperature analysis of air in a rectifying system having a rectifying column where compressed; passing purified air into a pressure column from which oxygen-free nitrogen pressure fraction is produced; passing the fraction into a low pressure column and producing as head gas carbon monoxide free low pressure nitrogen in the low pressure column.</p> |
