UREA GRANULATION PROCESS WITH SCRUBBING SYSTEM

摘要

Urea granulation process with scrubbing system including at least one gaseous waste stream for removal of dust and ammonia whereby this waste stream is processed through a combination of the following process steps comprising
(a) washing the dust and ammonia laden stream 4 with water and/or an aqueous urea solution whereby a dust-laden liquid stream 26 and a dust-reduced stream 5 is generated, and
(b) reacting the dust-reduced stream 5 with formaldeyhde 7 to form a stream 8
comprising hexamethylenetetramine and urea-formaldehyde and clean off-gas 6 wherein the gas stream is directed first through process step (a) and then through process step (b).