RECOVERY AND UTILIZATION OF UREA DUST AND AMMONIA IN EXHAUST GAS

摘要

PROBLEM TO BE SOLVED: To provide a method for recovering and utilizing urea dust and ammonia in exhaust gases discharged from a urea granulation unit. SOLUTION: This method is to pass exhaust gases containing urea dust and ammonia, discharged from a urea granulation unit, to a first scrubbing tower in which an aqueous urea solution is circulated to mainly recover the urea dust, then pass the treated gases to a second scrubbing tower in which acid-added water is circulated to mainly recover ammonia, and mix the recovered solutions with the stock for the urea granulation unit to produce the urea product.