GB286622A - Process for removing readily absorbed gases, more particularly carbon dioxide and sulphuretted hydrogen, from gas mixtures by absorption in water under pressure - Google Patents

Abstract

286,622. Ges. f³r Linde's Eismaschinen Akt.-Ges. March 5, 1927, [Convention date]. Washing processes for the removal of readily absorbed gases, more particularly sulphuretted hydrogen and carbon dioxide from gas mixtures by absorption in water under pressure which is subsequently regenerated, are effected in two towers in the first of which the sulphuretted hydrogen is washed with water saturated with carbon dioxide withdrawn from the second tower which receives regenerated water, the water containing sulphuretted hydrogen leaving the first tower being regenerated apart from the remaining water. A lignite gas containing 7.5 per cent of sulphuretted hydrogen and 30 per cent of carbon dioxide is compressed in a compressor 1 and the heat of compression absorbed in a refrigerator 2. The gas passes to a tower 3 receiving sufficient water through an inlet 4 to absorb the sulphuretted hydrogen and then enters a tower 8 fed with nearly double the amount of water through an inlet 10. Water from the tower 3 is reduced to atmospheric pressure in a turbine 7 and gas containing about 25 per cent of sulphuretted hydrogen is separated in a vessel 12, a further quantity of gas being removed in a separator 14 by a vacuum pump 15. These gases may be passed to Claus furnaces to recover sulphur. Last traces of sulphuretted hydrogen are removed in a tower 16 fed with ferric oxide or sulphur dioxide, the water collect. ing in a container 17. Water from the tower 8 after reduction of pressure in a turbine 24 passes to a separator 18 in which a gas containing about 75 per cent of carbon dioxide is obtained. A further quantity of carbon dioxide is expelled by aeration in a tower 20. Regenerated water collects in a container 21 and with that from the container 17 is returned to the system by a turbopump 22. To eliminate corrosion of the tower walls or pipes, alkali such as sodium carbonate may be added to the water. The removal of sulphur dioxide in the first tower from gases containing it together with carbon dioxide is referred to.