In the NPK fertilizer production process, technical challenges permeate the entire process, directly impacting product quality, production efficiency, and environmental protection levels. Targeted breakthroughs are needed to achieve high-quality industrial development, and these challenges are particularly evident in the operation of NPK fertilizer production lines.

Low granulation rate is the primary technical challenge. The physical properties of the mixed raw materials vary greatly. Nitrogen fertilizer is highly hygroscopic, and phosphate fertilizer is prone to clumping. If the moisture content is not properly controlled, it can lead to "sticking" or "scattering" phenomena when the NPK fertilizer granulator is running. In drum granulation, uneven raw material particle size can also cause excessive particle size variation, resulting in a low pass rate. Solving this problem requires a two-pronged approach: firstly, employing a graded crushing process and using sieves to ensure uniform raw material particle size; secondly, precisely selecting binders, such as adding an appropriate amount of humic acid to the formula, which can improve particle strength and reduce nutrient loss, effectively increasing the granulation rate.
Nutrient loss and equipment corrosion pose a dual challenge. During the high-temperature drying process, ammonium nitrogen is easily volatilized, causing a certain degree of processing loss. Simultaneously, acidic raw materials such as superphosphate can cause continuous corrosion to the reactor's inner wall, shortening the equipment's lifespan. To address nutrient loss, an appropriate amount of urease inhibitor can be added before drying to slow down nitrogen decomposition. For equipment corrosion, a composite anti-corrosion solution is required, including an enamel coating on the inner wall and titanium alloy stirring components, which can withstand acidic environments while preventing metal ion leaching and fertilizer contamination.
Furthermore, the stability of the slow-release process urgently needs to be addressed. Coated slow-release NPK fertilizers often suffer from large fluctuations in release cycles due to poor adhesion between the coating material (such as resin or sulfur) and the fertilizer particles, making it impossible to accurately match crop nutrient requirements. By adopting a "pre-coating + secondary curing" process, a dense base layer is first formed on the particle surface, and then low-temperature drying enhances coating adhesion, effectively controlling release cycle errors and significantly improving fertilizer utilization efficiency.
Overcoming these technical challenges requires a combination of process optimization and material innovation, along with real-time parameter adjustment using intelligent monitoring equipment, in order to drive NPK fertilizer production towards high efficiency, high quality, and green practices.