| 摘要 |
<p>1299772 Sulphuric acid BOLIDEN AB 19 Jan 1970 [23 Jan 1969] 2425/70 Heading C1A Sulphuric acid is made by the contact process in which an SO 2 containing gas, and obtained by burning sulphurous material with air in a furnace, is introduced into a contact apparatus wherein the major portion of the SO 2 is catalytically oxidized to SO 3 . This gas is then introduced into an absorption tower, where SO 3 and some SO 2 is absorbed in sulphuric acid. The sulphuric acid is then introduced into a ventilation tower, where it passes counter-current to air which takes up absorbed SO 2 from the sulphuric acid. The stripped sulphuric acid is then recycled to the absorption tower. The sulphurous material is usually sulphur, sulphur pyrite or other sulphide material. The air may be preheated, up to 350‹ C, before introduction into the ventilation tower, and the air from the ventilation tower may be partly conveyed to the combustion furnace and partly to the contact apparatus. The acid leaving the absorption tower may be diluted before being fed to the ventilation tower.</p> |
