Problem No. 43: Increased dust content of urea granules

Dust formation in the granulator can adversely affect stream time. There are several reasons for increased dust in the fluid bed granulator. No formaldehyde or less formaldehyde injection, lower bed level in the granulator, lower concentration of urea melt to the granulator, a higher pressure in atomisation (sprayer) air and a higher pressure in the urea melt header are all factors which can play a role. This roundtable discusses increased dust level and its causes.

Fateme Ahangarani from Razi Petrochemical Company, Iran starts the discussion: These days we have a problem in our urea granulation plant and the amount of product urea dust has increased. Which parameters are important for decreasing the dust content? We try to control the concentration of urea formaldehyde at about 0.5 wt-% but the problem still persists.