| 摘要 |
<p>1532659 Absorbent regeneration G GIAMMARCO and P GIAMMARCO 28 Nov 1975 [28 Nov 1974] 49121/75 Heading B1L [Also in Division C1] In the removal of acidic impurities, e.g. CO 2 , H 2 S, HCN, SO 2 , from a gaseous mixture by an absorption stage at 40-135‹C using an aqueous absorbent solution of alkali metal carbonates (alone or activated by amino acids, ethanolamines or arsenic trioxide), ethanolamines, amino acids, or alkali metal phosphates, sulphites, bisulphites or borates, followed by a regeneration stage wherein the impurities are stripped by steam from the absorbent, and the absorbent is then recycled (a) the regeneration stage comprises a principal regeneration column and a secondary regeneration column, the principal column operating at a higher pressure than the secondary column; (b) the spent absorbent solution is partially regenerated in one column after which at least part of the partially regenerated solution is fed to the other column for further regeneration; (c) the regeneration in the principal column is effected by steam introduced directly from outside or produced by boiling the solution present in that column, and the pressure in that column is controlled such that steam issuing from the top thereof is produced in quantities from 1.5 to 3 times the quantity corresponding to equilibrium conditions at the top of said column; and (d) the regeneration in the secondary column is effected predominantly by steam evolved by utilising the heat contained in the regenerated solution issuing from the principal regeneration column, e.g. by expansion of that solution to the secondary column pressure. A further secondary column may be provided which is fed by steam issuing from the main secondary column and through which is passed an absorbent fraction extracted from the upper portion of the principal column, this fraction then being returned to the principal column or passed through the main secondary column. The absorption stage may comprise an initial impurity absorption stage and a secondary heat absorption stage, part of the absorbent passing through both stages and part through the second stage only. The regeneration columns may also be multi-stage.</p> |
