Patent ID: 9149763
Filing Date: 2015-10-06
Classification: B01D,B01J,C05C

Abstract:
1. A method for reducing aerosol emissions from a urea granulation plant with a recovery of the resulting scrubber bleeds, comprising: producing urea granulates in a granulator by evaporating water from a concentrated urea solution and giving urea granulates and an exhaust of dust, ammonia and ammonium cyanate, and removing dust from the exhaust by scrubbing the exhaust in a scrubbing stage or removing the dust from the exhaust in a removing stage, and scrubbing a stream containing dust, ammonia, urea, and aerosols in an acid scrubbing stage, the acid scrubbing stage providing a first stream comprising mainly aerosols and a second stream comprising ammonium salts, and releasing a first stream of an exhaust of air, and a second stream of ammonium cyanate and water in an aerosol stage with spray and collection devices, and recovering the second stream of ammonium cyanate and water from the aerosol stage into the urea granulation plant or into a urea based fertilizer plant.