A recovery system (1) for processing a gas stream from a solidification unit (2) of a urea plant (3), in particular, a cooling air stream used in the solidification unit (2) and containing ammonia, comprises a scrubber (11) connected to the solidification unit (2), and a heat treating unit (12) connected by an inlet line (21) to a bottom outlet (18) of the scrubber (11) to receive a recovery solution produced in the scrubber (11) and containing at least one ammonia salt, and heating the recovery solution to a controlled temperature such as to degrade said at least one ammonia salt and produce gaseous ammonia for use in the urea plant (3), and at least one further acid ammonia salt or corresponding acid capable of capturing the ammonium group, to be reused in the scrubber (11) to remove ammonia from the gas stream from the solidification unit (2).
