| 摘要 |
<p>According to this process, the excess acidity in calcium sulphate is neutralised by a dry route by intimately mixing ground calcium sulphate and a solid base such as lime, sodium hydroxide or potassium hydroxide, and the reaction is carried out in a water vapour atmosphere. An apparatus for carrying out this process comprises successively a hopper (1) for feeding calcium sulphate and a silo (2) for lime or other pulverulent base interacting with an endless belt (8) transferring these products, independently of each other, to a weighing hopper (10) which directs the mixture of these products on to an endless screw (13) ending in a crusher (14) in which the crushed mixture is taken up by an air stream conveying it, after passing through a cyclone (16), to a mill (19) fed with water vapour and out of which the anhydrite is removed continuously. <IMAGE></p> |
