The relationship between moisture in urea products and weather
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I am in Xinjiang. It has been rainy recently, and high moisture content in urea products is a common issue. I would like to know the impact of air humidity on urea products and possible measures to address this problem
Air humidity has an impact on the moisture content in urea products, but this effect is difficult to control; generally, the outlet temperature of the second distillation step is increased to regulate the water content in these products
Our factory is located in the south, and there have been continuous heavy rains recently. This has led to high moisture content in the urea, causing it to clump together, which has a significant impact on product quality. Do any of you have any good suggestions?
The influence of atmospheric temperature and humidity on the water content in urea, in the context of the tower granulation process. From the granulation nozzle to the bottom of the tower, molten urea goes through three processes, namely the melt cooling process, the phase transition process, and the cooling process. The heat released by these three processes is absorbed by the air entering at the bottom of the tower. When the ambient temperature is high and the relative humidity is high, such that the water vapor partial pressure in the air entering the tower is greater than that on the surface of the solid urea, moisture from the atmosphere transfers into the finished urea. During the entire granulation process, urea tends to absorb moisture, which makes it easy for the water content in the final product to exceed the specified limits. Therefore, during the hot and humid summer months, the vacuum level of the evaporation system should be increased as much as possible during operation ； Conversely, when the ambient temperature is low and the relative air humidity is low, the water vapor partial pressure in the air entering the tower is less than that on the surface of the solid urea; in this case, the water content in the urea moves into the atmosphere, and during the entire granulation process, moisture is lost from the urea. As a result, the water content in the final product drops to very low levels, sometimes even around 0.15%. To prevent an increase in dust formation due to the low water content in the urea, it is necessary to maintain a lower vacuum level in the system during operation, in order to increase the water content in the final urea product. http://bbs.hcbbs.com/redirect.php?tid=494323&goto=lastpost
The book on urea caking and pulverization details the impact of weather on the urea granulation system, which can be adjusted through the automatic opening and closing of the louvers installed in this system.
Generally, the humidity is highest before and after it rains. It’s not clear whether it’s possible to reduce the impact by adjusting the opening of the louver blades on the granulation tower at such times, or by delaying release to the market for a while first. . . .
On rainy days when the air humidity is high, it is necessary to close or cover the louvers
I would like to ask fellow sailors: is it possible to add some kind of hydrophobic agent to urea?