Patent ID: 7837758

Claim:
A method for the production of solid urea ammonium sulphate (UAS) fertilizers, which comprises forming urea by reacting CO 2 and NH 3 in a urea reactor and subsequent carbamate stripper, and forming ammonium sulphate (AS) in situ by reacting H 2 SO 4 and NH 3 , free and/or as carbamate, in a reactor downstream of the carbamate stripper, wherein liquid effluent, containing urea, from the carbamate stripper is sent to the reactor for forming AS which is supplied with H 2 SO 4 and additional NH 3 such that reaction heat from the AS-formation is fully exploited for concentrating the urea and AS-solution, and then the urea and ammonium sulphate (AS) is mixed and particulated to form solid UAS-particles.