Generation of urea dust
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This post was last edited by lxq700918 on 2010-5-25 23:36. Why does the amount of dust increase in summer during tower-type nozzle granulation? Everyone is welcome to join the discussion.
Is it possible to consider the decomposition of molten urea into cyanic acid and gaseous ammonia? Since it is a decomposition reaction, as temperatures rise in summer the reaction intensifies, resulting in an increase in dust levels. Another factor is the high temperatures in summer, when thermal convection is significant; the wind speeds inside the tower are higher during summer than in winter, which also causes more powder particles to be blown out
1. One should not blindly pursue larger particle sizes; the load must be matched to the rotational speed. Otherwise, the temperature of urea in the lower tower will become too high, which means there will be more residual crystallization heat within the urea particles, resulting in them becoming more powdery. 2. The higher the packaging stack, the greater the likelihood of powdering. 3. The higher the water content in the finished product, the more powdery it becomes. 4. The content of organic substances in the CO2 feed gas is also one of the factors affecting particle strength.
Two pore sizes of granulation nozzles should be ordered: the slightly larger one for use in winter, and the smaller one for use in summer, which can help reduce dust. The pore size is determined by the nozzle manufacturer’s design.
Reply to 4# haic6062: Which manufacturer’s granulator and nozzles does your company use?
In summer, it is hot and humid. This results in high temperature and high moisture content of the urea in the lower tower, making it prone to pulverization
A selective dust collector can recover over a thousand tons of urea in one year
I think our answer might benefit from referring to the analysis by dsazse on floor 6 and the in-depth discussion by Erhai on floor 3