The granulation of mixed fertilizer in Npk production equipment is an important process of dry powder granulation process. It is not only related to the internal and external quality of the product, but also related to the size of the output and the level of cost. The granulation production process is not only related to the material itself In addition to the physical and chemical properties of the granulation equipment, it is also closely related to the form and mechanical properties of the granulation equipment. The main types of granulation equipment are disc granulator, drum granulator, twin-shaft granulator, extrusion granulator and spray granulation dryer. Then the frequently asked questions in the npk production line:
1. What is a return issue?
In the npk fertilizer manufacturing process, the material return problem is affected by the granulation temperature and humidity. Strict control of returning temperature, particle size distribution, granulation humidity and other factors is crucial to granulation.
2. How does the melting point of a material affect viscosity?
The melting point of the mixed material is lower than the lowest melting point of the components, and the eutectic point of urea, potassium chloride and monoammonium phosphate is about 115 degrees. This temperature is the sticking point temperature. The operating temperature of the pellets should be maintained at this temperature. With the increase of water content, the viscosity and temperature of urea compound fertilizer decreased. Therefore, high temperature and low water conditions will not improve the granulation conditions. What's more, it is not conducive to the drying and screening process.
When the difference in granulation temperature and humidity is smaller than air conditions, it is important to adapt to the external environment. The operation of the fertilizer granulator depends on the temperature and humidity of the granulation. The granulation temperature should be controlled between the viscosity temperature and the ambient temperature to maintain a suitable temperature. In this way, the material will not be too viscous and has a certain crystallization rate. The temperature and humidity of the material at the outlet of the granulator can be reduced, or two low-temperature dryers can be used. Although it increases the cost, it is reasonable for fertilizer production.