GB1379762A - Process for obtaining ammonium sulphate in a rotary reaction chamber - Google Patents

Abstract

1379762 Ammonium sulphate SOC ANON CROS 22 Nov 1971 [20 Nov 1970] 54176/71 Heading C1A Ammonium sulphate is made by reacting 40-60‹ B<SP>1</SP>e H 2 SO 4 directly with ammonia in a rotating reaction vessel on a bed of recycled solid ammonium sulphate at 30-120‹ C., the bed at the outlet of the vessel having pH 5À5-7, and a moisture content between 1 and 10%. The pH is defined as that of a 10% aqueous solution of the bed leaving the vessel outlet. In an embodiment, using an inclined rotary cylinder vessel, aqueous or anhydrous ammonia is introduced, via tubes provided with protective coulters or blades, into the interior of the solids bed at a depth of 100-600 mm. while H 2 SO 4 and/or H 2 O is sprayed over the bed (Specification 1,379,763). The H 2 SO 4 may similarly be introduced below the bed surface. In another embodiment; the reaction vessel is an inclined pan provided with sprays for the acid and/or H 2 O and a nozzle for ammonia below the bed surface. In an example, 100-800 kg./hr. of ammonium sulphate, recycled from drier and fines separator, is fed to a pan-type vessel and is sprayed with 300 kg./hr. of 53‹ B<SP>1</SP>e H 2 SO 4 and 10-70 kg./hr. H 2 O. Ammonia (72 kg./hr.) is injected into the bottom of the solids bed. The product is 275 kg./hr. of ammonium sulphate spheres (1-3 mm. dia.) of N 2 content 20À8- 21%.